Version bump fix

* [Demo] Remove Butterknife unbinder from MainActivity

* Make deploy_snapshot.sh executable

.travis.yml

@@ -14,14 +14,10 @@ jdk:
   - oraclejdk8
 
 branches:
-  only
-    - v2
+  only:
     - develop
     - master
 
-before_install:
-  - chmod +x .buildscript/deploy_snapshot.sh
-
 after_success:
   - .buildscript/deploy_snapshot.sh
 

README.md

@@ -20,22 +20,33 @@ Conductor is architecture-agnostic and does not try to force any design decision
 ## Installation
 
 ```gradle
-compile 'com.bluelinelabs:conductor:2.0.0'
+compile 'com.bluelinelabs:conductor:2.0.3'
 
 // If you want the components that go along with
 // Android's support libraries (currently just a PagerAdapter):
-compile 'com.bluelinelabs:conductor-support:2.0.0'
+compile 'com.bluelinelabs:conductor-support:2.0.3'
 
 // If you want RxJava/RxAndroid lifecycle support:
-compile 'com.bluelinelabs:conductor-rxlifecycle:2.0.0'
+compile 'com.bluelinelabs:conductor-rxlifecycle:2.0.3'
 ```
 
 SNAPSHOT:
 
 ```gradle
-compile 'com.bluelinelabs:conductor:2.0.1-SNAPSHOT'
-compile 'com.bluelinelabs:conductor-support:2.0.1-SNAPSHOT'
-compile 'com.bluelinelabs:conductor-rxlifecycle:2.0.1-SNAPSHOT'
+compile 'com.bluelinelabs:conductor:2.0.4-SNAPSHOT'
+compile 'com.bluelinelabs:conductor-support:2.0.4-SNAPSHOT'
+compile 'com.bluelinelabs:conductor-rxlifecycle:2.0.4-SNAPSHOT'
+```
+
+You also have to add the url to the snapshot repository:
+
+```gradle
+allprojects {
+  repositories {
+    ...
+
+    maven { url "https://oss.sonatype.org/content/repositories/snapshots/" }
+}
 ```
 
 ## Components to Know
@@ -114,7 +125,7 @@ The lifecycle of a Controller is significantly simpler to understand than that o
 `ControllerChangeHandler` can be subclassed in order to perform different functions when changing between two `Controllers`. Two convenience `ControllerChangeHandler` subclasses are included to cover most basic needs: `AnimatorChangeHandler`, which will use an `Animator` object to transition between two views, and `TransitionChangeHandler`, which will use Lollipop's `Transition` framework for transitioning between views.
 
 ### Child Routers & Controllers
-`getChildController` can be called on a `Controller` in order to get a nested `Router` into which child `Controller`s can be pushed. This enables creating advanced layouts, such as Master/Detail.
+`getChildRouter` can be called on a `Controller` in order to get a nested `Router` into which child `Controller`s can be pushed. This enables creating advanced layouts, such as Master/Detail.
 
 ### RxJava Lifecycle
 If the RxLifecycle dependency has been added, there is an `RxController` available that can be used along with the standard [RxLifecycle library](https://github.com/trello/RxLifecycle). There is also a `ControllerLifecycleProvider` available if you do not wish to use this subclass.

build.gradle

@@ -3,7 +3,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.1.2'
+        classpath 'com.android.tools.build:gradle:2.2.0'
     }
 }
 

conductor-rxlifecycle/build.gradle

@@ -28,6 +28,7 @@ dependencies {
     compile rootProject.ext.rxJava
     compile rootProject.ext.rxAndroid
     compile rootProject.ext.rxLifecycle
+    compile rootProject.ext.rxLifecycleAndroid
 
     compile project(':conductor')
 }

conductor-rxlifecycle/src/main/java/com/bluelinelabs/conductor/rxlifecycle/ControllerLifecycleProvider.java

@@ -1,38 +0,0 @@
-package com.bluelinelabs.conductor.rxlifecycle;
-
-import android.support.annotation.CheckResult;
-import android.support.annotation.NonNull;
-
-import rx.Observable;
-
-/**
- * Interface used for RxController. Can also be used if writing your own Controller component without subclassing RxController.
- */
-public interface ControllerLifecycleProvider {
-
-    /**
-     * @return An observable that will have all {@link com.bluelinelabs.conductor.Controller} lifecycle events
-     */
-    @NonNull
-    @CheckResult
-    Observable<ControllerEvent> lifecycle();
-
-    /**
-     * Will bind the source until a specific {@link ControllerEvent} occurs.
-     *
-     * @param event The {@link ControllerEvent} that should cause onComplete to be called
-     * @return A {@link rx.Observable.Transformer} that will call onComplete when the event occurs.
-     */
-    @NonNull
-    @CheckResult
-    <T> Observable.Transformer<T, T> bindUntilEvent(@NonNull ControllerEvent event);
-
-    /**
-     * Will bind the source until the next reasonable {@link ControllerEvent} occurs.
-     * @return A {@link rx.Observable.Transformer} that will call onComplete when the event occurs.
-     */
-    @NonNull
-    @CheckResult
-    <T> Observable.Transformer<T, T> bindToLifecycle();
-
-}

conductor-rxlifecycle/src/main/java/com/bluelinelabs/conductor/rxlifecycle/RxController.java

@@ -5,6 +5,8 @@ import android.support.annotation.CheckResult;
 import android.support.annotation.NonNull;
 
 import com.bluelinelabs.conductor.Controller;
+import com.trello.rxlifecycle.LifecycleProvider;
+import com.trello.rxlifecycle.LifecycleTransformer;
 import com.trello.rxlifecycle.RxLifecycle;
 
 import rx.Observable;
@@ -13,7 +15,7 @@ import rx.subjects.BehaviorSubject;
 /**
  * A base {@link Controller} that can be used to expose lifecycle events using RxJava
  */
-public abstract class RxController extends Controller implements ControllerLifecycleProvider {
+public abstract class RxController extends Controller implements LifecycleProvider<ControllerEvent> {
 
     private final BehaviorSubject<ControllerEvent> lifecycleSubject;
 
@@ -36,14 +38,14 @@ public abstract class RxController extends Controller implements ControllerLifec
     @Override
     @NonNull
     @CheckResult
-    public final <T> Observable.Transformer<T, T> bindUntilEvent(@NonNull ControllerEvent event) {
+    public final <T> LifecycleTransformer<T> bindUntilEvent(@NonNull ControllerEvent event) {
         return RxLifecycle.bindUntilEvent(lifecycleSubject, event);
     }
 
     @Override
     @NonNull
     @CheckResult
-    public final <T> Observable.Transformer<T, T> bindToLifecycle() {
+    public final <T> LifecycleTransformer<T> bindToLifecycle() {
         return RxControllerLifecycle.bindController(lifecycleSubject);
     }
 

conductor-rxlifecycle/src/main/java/com/bluelinelabs/conductor/rxlifecycle/RxControllerLifecycle.java

@@ -14,7 +14,7 @@ public class RxControllerLifecycle {
 
     /**
      * Binds the given source to a Controller lifecycle. This is the Controller version of
-     * {@link com.trello.rxlifecycle.RxLifecycle#bindFragment(Observable)}.
+     * {@link com.trello.rxlifecycle.android.RxLifecycleAndroid#bindFragment(Observable)}.
      *
      * @param lifecycle the lifecycle sequence of a Controller
      * @return a reusable {@link Observable.Transformer} that unsubscribes the source during the Controller lifecycle

conductor/src/main/java/com/bluelinelabs/conductor/ActivityHostedRouter.java

@@ -92,4 +92,9 @@ public class ActivityHostedRouter extends Router {
     List<Router> getSiblingRouters() {
         return lifecycleHandler.getRouters();
     }
+
+    @Override
+    Router getRootRouter() {
+        return this;
+    }
 }

conductor/src/main/java/com/bluelinelabs/conductor/Controller.java

@@ -24,6 +24,7 @@ import com.bluelinelabs.conductor.ControllerChangeHandler.ControllerChangeListen
 import com.bluelinelabs.conductor.internal.ClassUtils;
 import com.bluelinelabs.conductor.internal.RouterRequiringFunc;
 
+import java.lang.ref.WeakReference;
 import java.lang.reflect.Constructor;
 import java.util.ArrayDeque;
 import java.util.ArrayList;
@@ -54,10 +55,11 @@ public abstract class Controller {
     private static final String KEY_OVERRIDDEN_POP_HANDLER = "Controller.overriddenPopHandler";
     private static final String KEY_VIEW_STATE_HIERARCHY = "Controller.viewState.hierarchy";
     private static final String KEY_VIEW_STATE_BUNDLE = "Controller.viewState.bundle";
+    private static final String KEY_RETAIN_VIEW_MODE = "Controller.retainViewMode";
 
     private final Bundle args;
 
-    private Bundle viewState;
+    Bundle viewState;
     private Bundle savedInstanceState;
     private boolean isBeingDestroyed;
     private boolean destroyed;
@@ -83,6 +85,7 @@ public abstract class Controller {
     private final ArrayList<String> requestedPermissions = new ArrayList<>();
     private final ArrayList<RouterRequiringFunc> onRouterSetListeners = new ArrayList<>();
     private final Deque<Controller> childBackstack = new ArrayDeque<>();
+    private WeakReference<View> destroyedView;
 
     private final ControllerChangeListener childRouterChangeListener = new ControllerChangeListener() {
         @Override
@@ -312,7 +315,10 @@ public abstract class Controller {
      * @return This Controller's target
      */
     public final Controller getTargetController() {
-        return targetInstanceId != null ? router.getControllerWithInstanceId(targetInstanceId) : null;
+        if (targetInstanceId != null) {
+            return router.getRootRouter().getControllerWithInstanceId(targetInstanceId);
+        }
+        return null;
     }
 
     /**
@@ -641,6 +647,10 @@ public abstract class Controller {
         return false;
     }
 
+    final void setNeedsAttach() {
+        needsAttach = true;
+    }
+
     final void prepareForHostDetach() {
         needsAttach = needsAttach || attached;
 
@@ -692,6 +702,8 @@ public abstract class Controller {
     final void activityResumed(Activity activity) {
         if (!attached && view != null && viewIsAttached) {
             attach(view);
+        } else if (attached) {
+            needsAttach = false;
         }
 
         onActivityResumed(activity);
@@ -734,7 +746,7 @@ public abstract class Controller {
         }
     }
 
-    private void detach(@NonNull View view, boolean forceViewRefRemoval) {
+    void detach(@NonNull View view, boolean forceViewRefRemoval) {
         for (ControllerHostedRouter router : childRouters) {
             router.prepareForHostDetach();
         }
@@ -777,6 +789,10 @@ public abstract class Controller {
 
             view.removeOnAttachStateChangeListener(onAttachStateChangeListener);
             viewIsAttached = false;
+
+            if (isBeingDestroyed) {
+                destroyedView = new WeakReference<>(view);
+            }
             view = null;
 
             for (LifecycleListener lifecycleListener : lifecycleListeners) {
@@ -839,7 +855,7 @@ public abstract class Controller {
         return view;
     }
 
-    final void performDestroy() {
+    private void performDestroy() {
         if (!destroyed) {
             for (LifecycleListener lifecycleListener : lifecycleListeners) {
                 lifecycleListener.preDestroy(this);
@@ -847,10 +863,6 @@ public abstract class Controller {
 
             destroyed = true;
 
-            if (router != null) {
-                router.unregisterForActivityResults(instanceId);
-            }
-
             onDestroy();
 
             parentController = null;
@@ -865,9 +877,13 @@ public abstract class Controller {
         destroy(false);
     }
 
-    final void destroy(boolean removeViews) {
+    private void destroy(boolean removeViews) {
         isBeingDestroyed = true;
 
+        if (router != null) {
+            router.unregisterForActivityResults(instanceId);
+        }
+
         for (ControllerHostedRouter childRouter : childRouters) {
             childRouter.destroy();
         }
@@ -879,7 +895,7 @@ public abstract class Controller {
         }
     }
 
-    final void saveViewState(@NonNull View view) {
+    private void saveViewState(@NonNull View view) {
         hasSavedViewState = true;
 
         viewState = new Bundle();
@@ -897,7 +913,7 @@ public abstract class Controller {
         }
     }
 
-    final void restoreViewState(@NonNull View view) {
+    private void restoreViewState(@NonNull View view) {
         if (viewState != null) {
             view.restoreHierarchyState(viewState.getSparseParcelableArray(KEY_VIEW_STATE_HIERARCHY));
             onRestoreViewState(view, viewState.getBundle(KEY_VIEW_STATE_BUNDLE));
@@ -908,6 +924,7 @@ public abstract class Controller {
 
                     if (containerView != null && containerView instanceof ViewGroup) {
                         childRouter.setHost(this, (ViewGroup)containerView);
+                        monitorChildRouter(childRouter);
                         childRouter.rebindIfNeeded();
                     }
                 }
@@ -932,6 +949,7 @@ public abstract class Controller {
         outState.putString(KEY_TARGET_INSTANCE_ID, targetInstanceId);
         outState.putStringArrayList(KEY_REQUESTED_PERMISSIONS, requestedPermissions);
         outState.putBoolean(KEY_NEEDS_ATTACH, needsAttach || attached);
+        outState.putInt(KEY_RETAIN_VIEW_MODE, retainViewMode.ordinal());
 
         if (overriddenPushHandler != null) {
             outState.putBundle(KEY_OVERRIDDEN_PUSH_HANDLER, overriddenPushHandler.toBundle());
@@ -968,6 +986,7 @@ public abstract class Controller {
         overriddenPushHandler = ControllerChangeHandler.fromBundle(savedInstanceState.getBundle(KEY_OVERRIDDEN_PUSH_HANDLER));
         overriddenPopHandler = ControllerChangeHandler.fromBundle(savedInstanceState.getBundle(KEY_OVERRIDDEN_POP_HANDLER));
         needsAttach = savedInstanceState.getBoolean(KEY_NEEDS_ATTACH);
+        retainViewMode = RetainViewMode.values()[savedInstanceState.getInt(KEY_RETAIN_VIEW_MODE, 0)];
 
         List<Bundle> childBundles = savedInstanceState.getParcelableArrayList(KEY_CHILD_ROUTERS);
         for (Bundle childBundle : childBundles) {
@@ -1019,6 +1038,13 @@ public abstract class Controller {
         for (LifecycleListener lifecycleListener : lifecycleListeners) {
             lifecycleListener.onChangeEnd(this, changeHandler, changeType);
         }
+
+        if (isBeingDestroyed && !viewIsAttached && !attached && destroyedView != null) {
+            View view = destroyedView.get();
+            if (router.container != null && view.getParent() == router.container) {
+                router.container.removeView(view);
+            }
+        }
     }
 
     final void setDetachFrozen(boolean frozen) {
@@ -1036,28 +1062,19 @@ public abstract class Controller {
     }
 
     final void createOptionsMenu(Menu menu, MenuInflater inflater) {
-        if (attached) {
-            if (hasOptionsMenu && !optionsMenuHidden) {
-                onCreateOptionsMenu(menu, inflater);
-            }
+        if (attached && hasOptionsMenu && !optionsMenuHidden) {
+            onCreateOptionsMenu(menu, inflater);
         }
     }
 
     final void prepareOptionsMenu(Menu menu) {
-        if (attached) {
-            if (hasOptionsMenu && !optionsMenuHidden) {
-                onPrepareOptionsMenu(menu);
-            }
+        if (attached && hasOptionsMenu && !optionsMenuHidden) {
+            onPrepareOptionsMenu(menu);
         }
     }
 
     final boolean optionsItemSelected(MenuItem item) {
-        if (attached) {
-            if (hasOptionsMenu && !optionsMenuHidden && onOptionsItemSelected(item)) {
-                return true;
-            }
-        }
-        return false;
+        return attached && hasOptionsMenu && !optionsMenuHidden && onOptionsItemSelected(item);
     }
 
     private void monitorChildRouter(ControllerHostedRouter childRouter) {
@@ -1065,13 +1082,15 @@ public abstract class Controller {
     }
 
     private void onChildControllerPushed(Controller controller) {
-        childBackstack.add(controller);
-        controller.addLifecycleListener(new LifecycleListener() {
-            @Override
-            public void postDestroy(@NonNull Controller controller) {
-                childBackstack.remove(controller);
-            }
-        });
+        if (!childBackstack.contains(controller)) {
+            childBackstack.add(controller);
+            controller.addLifecycleListener(new LifecycleListener() {
+                @Override
+                public void postDestroy(@NonNull Controller controller) {
+                    childBackstack.remove(controller);
+                }
+            });
+        }
     }
 
     final void setParentController(Controller controller) {
@@ -1137,6 +1156,7 @@ public abstract class Controller {
 
         public void onSaveViewState(@NonNull Controller controller, @NonNull Bundle outState) { }
         public void onRestoreViewState(@NonNull Controller controller, @NonNull Bundle savedViewState) { }
+
     }
 
 }

conductor/src/main/java/com/bluelinelabs/conductor/ControllerChangeHandler.java

@@ -4,6 +4,7 @@ import android.os.Bundle;
 import android.support.annotation.NonNull;
 import android.view.View;
 import android.view.ViewGroup;
+import android.view.ViewParent;
 
 import com.bluelinelabs.conductor.changehandler.SimpleSwapChangeHandler;
 import com.bluelinelabs.conductor.internal.ClassUtils;
@@ -25,13 +26,15 @@ public abstract class ControllerChangeHandler {
 
     private static final Map<String, ControllerChangeHandler> inProgressPushHandlers = new HashMap<>();
 
+    private boolean forceRemoveViewOnPush;
+
     /**
      * Responsible for swapping Views from one Controller to another.
      *
-     * @param container The container these Views are hosted in.
-     * @param from The previous View in the container, if any.
-     * @param to The next View that should be put in the container, if any.
-     * @param isPush True if this is a push transaction, false if it's a pop.
+     * @param container      The container these Views are hosted in.
+     * @param from           The previous View in the container, if any.
+     * @param to             The next View that should be put in the container, if any.
+     * @param isPush         True if this is a push transaction, false if it's a pop.
      * @param changeListener This listener must be called when any transitions or animations are completed.
      */
     public abstract void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener);
@@ -59,10 +62,16 @@ public abstract class ControllerChangeHandler {
      * popped before it has completed.
      *
      * @param newHandler the change handler that has caused this push to be aborted
-     * @param newTop the controller that will now be at the top of the backstack
+     * @param newTop     the controller that will now be at the top of the backstack
      */
     public void onAbortPush(@NonNull ControllerChangeHandler newHandler, Controller newTop) { }
 
+    /**
+     * Will be called on change handlers that push a controller if the controller being pushed is
+     * needs to be attached immediately, without any animations or transitions.
+     */
+    public void completeImmediately() { }
+
     final Bundle toBundle() {
         Bundle bundle = new Bundle();
         bundle.putString(KEY_CLASS_NAME, getClass().getName());
@@ -74,6 +83,10 @@ public abstract class ControllerChangeHandler {
         return bundle;
     }
 
+    final ControllerChangeHandler copy() {
+        return fromBundle(toBundle());
+    }
+
     private void ensureDefaultConstructor() {
         try {
             getClass().getConstructor();
@@ -94,6 +107,24 @@ public abstract class ControllerChangeHandler {
         }
     }
 
+    static boolean completePushImmediately(String controllerInstanceId) {
+        ControllerChangeHandler changeHandler = inProgressPushHandlers.get(controllerInstanceId);
+        if (changeHandler != null) {
+            changeHandler.completeImmediately();
+            inProgressPushHandlers.remove(controllerInstanceId);
+            return true;
+        }
+        return false;
+    }
+
+    public static void abortPush(Controller toAbort, Controller newController, ControllerChangeHandler newChangeHandler) {
+        ControllerChangeHandler handlerForPush = inProgressPushHandlers.get(toAbort.getInstanceId());
+        if (handlerForPush != null) {
+            handlerForPush.onAbortPush(newChangeHandler, newController);
+            inProgressPushHandlers.remove(toAbort.getInstanceId());
+        }
+    }
+
     public static void executeChange(final Controller to, final Controller from, boolean isPush, ViewGroup container, ControllerChangeHandler inHandler) {
         executeChange(to, from, isPush, container, inHandler, new ArrayList<ControllerChangeListener>());
     }
@@ -102,14 +133,10 @@ public abstract class ControllerChangeHandler {
         if (container != null) {
             final ControllerChangeHandler handler = inHandler != null ? inHandler : new SimpleSwapChangeHandler();
 
-            if (isPush) {
+            if (isPush && to != null) {
                 inProgressPushHandlers.put(to.getInstanceId(), handler);
-            } else if (from != null) {
-                ControllerChangeHandler handlerForPush = inProgressPushHandlers.get(from.getInstanceId());
-                if (handlerForPush != null) {
-                    handlerForPush.onAbortPush(handler, to);
-                    inProgressPushHandlers.remove(from.getInstanceId());
-                }
+            } else if (!isPush && from != null) {
+                abortPush(from, to, handler);
             }
 
             for (ControllerChangeListener listener : listeners) {
@@ -138,7 +165,6 @@ public abstract class ControllerChangeHandler {
             handler.performChange(container, fromView, toView, isPush, new ControllerChangeCompletedListener() {
                 @Override
                 public void onChangeCompleted() {
-
                     if (from != null) {
                         from.changeEnded(handler, fromChangeType);
                     }
@@ -151,11 +177,26 @@ public abstract class ControllerChangeHandler {
                     for (ControllerChangeListener listener : listeners) {
                         listener.onChangeCompleted(to, from, isPush, container, inHandler);
                     }
+
+                    if (handler.forceRemoveViewOnPush && fromView != null) {
+                        ViewParent fromParent = fromView.getParent();
+                        if (fromParent != null && fromParent instanceof ViewGroup) {
+                            ((ViewGroup)fromParent).removeView(fromView);
+                        }
+                    }
                 }
             });
         }
     }
 
+    public boolean removesFromViewOnPush() {
+        return true;
+    }
+
+    public void setForceRemoveViewOnPush(boolean force) {
+        forceRemoveViewOnPush = force;
+    }
+
     /**
      * A listener interface useful for allowing external classes to be notified of change events.
      */
@@ -163,21 +204,22 @@ public abstract class ControllerChangeHandler {
         /**
          * Called when a {@link ControllerChangeHandler} has started changing {@link Controller}s
          *
-         * @param to The new Controller
-         * @param from The old Controller
-         * @param isPush True if this is a push operation, or false if it's a pop.
+         * @param to        The new Controller
+         * @param from      The old Controller
+         * @param isPush    True if this is a push operation, or false if it's a pop.
          * @param container The containing ViewGroup
-         * @param handler The change handler being used.
+         * @param handler   The change handler being used.
          */
         void onChangeStarted(Controller to, Controller from, boolean isPush, ViewGroup container, ControllerChangeHandler handler);
 
         /**
          * Called when a {@link ControllerChangeHandler} has completed changing {@link Controller}s
-         * @param to The new Controller
-         * @param from The old Controller
-         * @param isPush True if this was a push operation, or false if it's a pop.
+         *
+         * @param to        The new Controller
+         * @param from      The old Controller
+         * @param isPush    True if this was a push operation, or false if it's a pop.
          * @param container The containing ViewGroup
-         * @param handler The change handler that was used.
+         * @param handler   The change handler that was used.
          */
         void onChangeCompleted(Controller to, Controller from, boolean isPush, ViewGroup container, ControllerChangeHandler handler);
     }

conductor/src/main/java/com/bluelinelabs/conductor/ControllerHostedRouter.java

@@ -12,7 +12,7 @@ import com.bluelinelabs.conductor.ControllerChangeHandler.ControllerChangeListen
 import java.util.ArrayList;
 import java.util.List;
 
-public class ControllerHostedRouter extends Router {
+class ControllerHostedRouter extends Router {
 
     private final String KEY_HOST_ID = "ControllerHostedRouter.hostId";
     private final String KEY_TAG = "ControllerHostedRouter.tag";
@@ -22,14 +22,14 @@ public class ControllerHostedRouter extends Router {
     @IdRes private int hostId;
     private String tag;
 
-    public ControllerHostedRouter() { }
+    ControllerHostedRouter() { }
 
-    public ControllerHostedRouter(int hostId, String tag) {
+    ControllerHostedRouter(int hostId, String tag) {
         this.hostId = hostId;
         this.tag = tag;
     }
 
-    public final void setHost(@NonNull Controller controller, @NonNull ViewGroup container) {
+    final void setHost(@NonNull Controller controller, @NonNull ViewGroup container) {
         if (hostController != controller || this.container != container) {
             removeHost();
 
@@ -42,22 +42,40 @@ public class ControllerHostedRouter extends Router {
         }
     }
 
-    public final void removeHost() {
+    final void removeHost() {
         if (container != null && container instanceof ControllerChangeListener) {
             removeChangeListener((ControllerChangeListener)container);
         }
 
+        final List<Controller> controllersToDestroy = new ArrayList<>(destroyingControllers);
+        for (Controller controller : controllersToDestroy) {
+            if (controller.getView() != null) {
+                controller.detach(controller.getView(), true);
+            }
+        }
+        for (RouterTransaction transaction : backstack) {
+            if (transaction.controller.getView() != null) {
+                transaction.controller.detach(transaction.controller.getView(), true);
+            }
+        }
+
         prepareForContainerRemoval();
         hostController = null;
         container = null;
     }
 
-    public final void setDetachFrozen(boolean frozen) {
-        for (RouterTransaction transaction : backStack) {
+    final void setDetachFrozen(boolean frozen) {
+        for (RouterTransaction transaction : backstack) {
             transaction.controller.setDetachFrozen(frozen);
         }
     }
 
+    @Override
+    void destroy() {
+        setDetachFrozen(false);
+        super.destroy();
+    }
+
     @Override
     public Activity getActivity() {
         return hostController != null ? hostController.getActivity() : null;
@@ -153,11 +171,11 @@ public class ControllerHostedRouter extends Router {
         controller.setParentController(hostController);
     }
 
-    public int getHostId() {
+    int getHostId() {
         return hostId;
     }
 
-    public String getTag() {
+    String getTag() {
         return tag;
     }
 
@@ -168,4 +186,13 @@ public class ControllerHostedRouter extends Router {
         list.addAll(hostController.getRouter().getSiblingRouters());
         return list;
     }
+
+    @Override
+    Router getRootRouter() {
+        if (hostController != null && hostController.getRouter() != null) {
+            return hostController.getRouter().getRootRouter();
+        } else {
+            return this;
+        }
+    }
 }

conductor/src/main/java/com/bluelinelabs/conductor/RestoreViewOnCreateController.java

@@ -0,0 +1,38 @@
+package com.bluelinelabs.conductor;
+
+import android.os.Bundle;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+/**
+ * A simple controller subclass that changes the onCreateView signature to include a saved view state parameter.
+ * This is necessary for some third party libraries like Google Maps, which require passing in a saved state
+ * bundle at the time of creation.
+ */
+abstract public class RestoreViewOnCreateController extends Controller {
+
+    @NonNull
+    @Override
+    protected final View onCreateView(@NonNull LayoutInflater inflater, @NonNull ViewGroup container) {
+        return onCreateView(inflater, container, viewState);
+    }
+
+    /**
+     * Called when the controller is ready to display its view. A valid view must be returned. The standard body
+     * for this method will be {@code return inflater.inflate(R.layout.my_layout, container, false);}, plus
+     * any binding and state restoration code.
+     *
+     * @param inflater       The LayoutInflater that should be used to inflate views
+     * @param container      The parent view that this Controller's view will eventually be attached to.
+     *                       This Controller's view should NOT be added in this method. It is simply passed in
+     *                       so that valid LayoutParams can be used during inflation.
+     * @param savedViewState A bundle for the view's state, which would have been created in {@link #onSaveViewState(View, Bundle)},
+     *                       or null if no saved state exists.
+     */
+    @NonNull
+    protected abstract View onCreateView(@NonNull LayoutInflater inflater, @NonNull ViewGroup container, @Nullable Bundle savedViewState);
+
+}

conductor/src/main/java/com/bluelinelabs/conductor/Router.java

@@ -16,6 +16,7 @@ import com.bluelinelabs.conductor.changehandler.SimpleSwapChangeHandler;
 import com.bluelinelabs.conductor.internal.NoOpControllerChangeHandler;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 
@@ -29,9 +30,9 @@ public abstract class Router {
     private static final String KEY_BACKSTACK = "Router.backstack";
     private static final String KEY_POPS_LAST_VIEW = "Router.popsLastView";
 
-    protected final Backstack backStack = new Backstack();
+    protected final Backstack backstack = new Backstack();
     private final List<ControllerChangeListener> changeListeners = new ArrayList<>();
-    private final List<Controller> destroyingControllers = new ArrayList<>();
+    final List<Controller> destroyingControllers = new ArrayList<>();
 
     private boolean popsLastView = false;
 
@@ -71,10 +72,12 @@ public abstract class Router {
     /**
      * This should be called by the host Activity when its onBackPressed method is called. The call will be forwarded
      * to its top {@link Controller}. If that controller doesn't handle it, then it will be popped.
+     *
+     * @return Whether or not a back action was handled by the Router
      */
     public boolean handleBack() {
-        if (!backStack.isEmpty()) {
-            if (backStack.peek().controller.handleBack()) {
+        if (!backstack.isEmpty()) {
+            if (backstack.peek().controller.handleBack()) {
                 return true;
             } else if (popCurrentController()) {
                 return true;
@@ -90,7 +93,7 @@ public abstract class Router {
      * @return Whether or not this Router still has controllers remaining on it after popping.
      */
     public boolean popCurrentController() {
-        return popController(backStack.peek().controller);
+        return popController(backstack.peek().controller);
     }
 
     /**
@@ -100,28 +103,28 @@ public abstract class Router {
      * @return Whether or not this Router still has controllers remaining on it after popping.
      */
     public boolean popController(Controller controller) {
-        RouterTransaction topController = backStack.peek();
+        RouterTransaction topController = backstack.peek();
         boolean poppingTopController = topController != null && topController.controller == controller;
 
         if (poppingTopController) {
-            trackDestroyingController(backStack.pop());
+            trackDestroyingController(backstack.pop());
         } else {
-            for (RouterTransaction transaction : backStack) {
+            for (RouterTransaction transaction : backstack) {
                 if (transaction.controller == controller) {
-                    backStack.remove(transaction);
+                    backstack.remove(transaction);
                     break;
                 }
             }
         }
 
         if (poppingTopController) {
-            performControllerChange(backStack.peek(), topController, false);
+            performControllerChange(backstack.peek(), topController, false);
         }
 
         if (popsLastView) {
             return topController != null;
         } else {
-            return !backStack.isEmpty();
+            return !backstack.isEmpty();
         }
     }
 
@@ -132,7 +135,7 @@ public abstract class Router {
      *                    and its push and pop {@link ControllerChangeHandler}, and its tag.
      */
     public void pushController(@NonNull RouterTransaction transaction) {
-        RouterTransaction from = backStack.peek();
+        RouterTransaction from = backstack.peek();
         pushToBackstack(transaction);
         performControllerChange(transaction, from, true);
     }
@@ -144,18 +147,31 @@ public abstract class Router {
      *                    and its push and pop {@link ControllerChangeHandler}, and its tag.
      */
     public void replaceTopController(@NonNull RouterTransaction transaction) {
-        RouterTransaction topTransaction = backStack.peek();
-        if (!backStack.isEmpty()) {
-            trackDestroyingController(backStack.pop());
+        RouterTransaction topTransaction = backstack.peek();
+        if (!backstack.isEmpty()) {
+            trackDestroyingController(backstack.pop());
+        }
+
+        final ControllerChangeHandler handler = transaction.pushChangeHandler();
+        final boolean oldHandlerRemovedViews = topTransaction.pushChangeHandler() == null || topTransaction.pushChangeHandler().removesFromViewOnPush();
+        final boolean newHandlerRemovesViews = handler == null || handler.removesFromViewOnPush();
+        if (!oldHandlerRemovedViews && newHandlerRemovesViews) {
+            for (RouterTransaction visibleTransaction : getVisibleTransactions(backstack.iterator())) {
+                performControllerChange(null, visibleTransaction.controller, true, handler != null ? handler.copy() : new SimpleSwapChangeHandler());
+            }
         }
 
         pushToBackstack(transaction);
-        performControllerChange(transaction, topTransaction, true);
+
+        if (handler != null) {
+            handler.setForceRemoveViewOnPush(true);
+        }
+        performControllerChange(transaction.pushChangeHandler(handler), topTransaction, true);
     }
 
     void destroy() {
         popsLastView = true;
-        List<RouterTransaction> poppedControllers = backStack.popAll();
+        List<RouterTransaction> poppedControllers = backstack.popAll();
 
         if (poppedControllers.size() > 0) {
             trackDestroyingControllers(poppedControllers);
@@ -164,9 +180,13 @@ public abstract class Router {
         }
     }
 
+    public int getContainerId() {
+        return container != null ? container.getId() : 0;
+    }
+
     /**
      * If set to true, this router will handle back presses by performing a change handler on the last controller and view
-     * in the stack. This defaults to false so that the developer can either finish its containing Activity or otherwise 
+     * in the stack. This defaults to false so that the developer can either finish its containing Activity or otherwise
      * hide its parent view without any strange artifacting.
      */
     public Router setPopsLastView(boolean popsLastView) {
@@ -190,8 +210,8 @@ public abstract class Router {
      * @return Whether or not any {@link Controller}s were popped in order to get to the root transaction
      */
     public boolean popToRoot(ControllerChangeHandler changeHandler) {
-        if (backStack.size() > 1) {
-            popToTransaction(backStack.root(), changeHandler);
+        if (backstack.size() > 1) {
+            popToTransaction(backstack.root(), changeHandler);
             return true;
         } else {
             return false;
@@ -216,7 +236,7 @@ public abstract class Router {
      * @return Whether or not the {@link Controller} with the passed tag is now at the top
      */
     public boolean popToTag(@NonNull String tag, ControllerChangeHandler changeHandler) {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             if (tag.equals(transaction.tag())) {
                 popToTransaction(transaction, changeHandler);
                 return true;
@@ -232,13 +252,29 @@ public abstract class Router {
      *                    and its push and pop {@link ControllerChangeHandler}, and its tag.
      */
     public void setRoot(@NonNull RouterTransaction transaction) {
-        RouterTransaction currentTop = backStack.peek();
-        removeAllExceptTopAndUnowned();
+        ControllerChangeHandler newHandler = transaction.pushChangeHandler() != null ? transaction.pushChangeHandler() : new SimpleSwapChangeHandler();
 
-        trackDestroyingControllers(backStack.popAll());
+        List<RouterTransaction> visibleTransactions = getVisibleTransactions(backstack.iterator());
+        RouterTransaction rootTransaction = visibleTransactions.size() > 0 ? visibleTransactions.get(0) : null;
+
+        removeAllExceptVisibleAndUnowned();
+
+        trackDestroyingControllers(backstack.popAll());
 
         pushToBackstack(transaction);
-        performControllerChange(transaction, currentTop, true);
+
+        for (int i = visibleTransactions.size() - 1; i > 0; i--) {
+            if (visibleTransactions.get(i).controller.getView() == null) {
+                ControllerChangeHandler.abortPush(visibleTransactions.get(i).controller, transaction.controller, newHandler);
+            } else {
+                performControllerChange(null, visibleTransactions.get(i).controller, true, newHandler);
+            }
+        }
+
+        if (rootTransaction != null && rootTransaction.controller.getView() == null) {
+            ControllerChangeHandler.abortPush(rootTransaction.controller, transaction.controller, newHandler);
+        }
+        performControllerChange(transaction, rootTransaction, true);
     }
 
     /**
@@ -248,7 +284,7 @@ public abstract class Router {
      * @return The matching Controller, if one exists
      */
     public Controller getControllerWithInstanceId(String instanceId) {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             Controller controllerWithId = transaction.controller.findController(instanceId);
             if (controllerWithId != null) {
                 return controllerWithId;
@@ -264,7 +300,7 @@ public abstract class Router {
      * @return The matching Controller, if one exists
      */
     public Controller getControllerWithTag(String tag) {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             if (tag.equals(transaction.tag())) {
                 return transaction.controller;
             }
@@ -276,7 +312,7 @@ public abstract class Router {
      * Returns the number of {@link Controller}s currently in the backstack
      */
     public int getBackstackSize() {
-        return backStack.size();
+        return backstack.size();
     }
 
     /**
@@ -284,7 +320,7 @@ public abstract class Router {
      */
     public List<RouterTransaction> getBackstack() {
         List<RouterTransaction> list = new ArrayList<>();
-        Iterator<RouterTransaction> backstackIterator = backStack.reverseIterator();
+        Iterator<RouterTransaction> backstackIterator = backstack.reverseIterator();
         while (backstackIterator.hasNext()) {
             list.add(backstackIterator.next());
         }
@@ -295,20 +331,47 @@ public abstract class Router {
      * Sets the backstack, transitioning from the current top controller to the top of the new stack (if different)
      * using the passed {@link ControllerChangeHandler}
      *
-     * @param backstack The new backstack
-     * @param changeHandler An optional change handler to be used to handle the transition
+     * @param newBackstack The new backstack
+     * @param changeHandler An optional change handler to be used to handle the root view of transition
      */
-    public void setBackstack(@NonNull List<RouterTransaction> backstack, ControllerChangeHandler changeHandler) {
-        RouterTransaction oldTopTransaction = backStack.peek();
-        Controller oldTop = oldTopTransaction != null ? oldTopTransaction.controller : null;
-        removeAllExceptTopAndUnowned();
+    public void setBackstack(@NonNull List<RouterTransaction> newBackstack, ControllerChangeHandler changeHandler) {
+        List<RouterTransaction> oldVisibleTransactions = getVisibleTransactions(backstack.iterator());
 
-        if (backstack.size() > 0) {
-            Controller newTop = backstack.get(backstack.size() - 1).controller;
+        removeAllExceptVisibleAndUnowned();
 
-            if (newTop != oldTop) {
+        if (newBackstack.size() > 0) {
+            List<RouterTransaction> reverseNewBackstack = new ArrayList<>(newBackstack);
+            Collections.reverse(reverseNewBackstack);
+            List<RouterTransaction> newVisibleTransactions = getVisibleTransactions(reverseNewBackstack.iterator());
+
+            boolean visibleTransactionsChanged = newVisibleTransactions.size() != oldVisibleTransactions.size();
+            if (!visibleTransactionsChanged) {
+                for (int i = 0; i < oldVisibleTransactions.size(); i++) {
+                    if (oldVisibleTransactions.get(i).controller != newVisibleTransactions.get(i).controller) {
+                        visibleTransactionsChanged = true;
+                        break;
+                    }
+                }
+            }
+
+            if (visibleTransactionsChanged) {
                 ControllerChangeHandler handler = changeHandler != null ? changeHandler : new SimpleSwapChangeHandler();
-                performControllerChange(newTop, oldTop, true, handler);
+
+                Controller rootController = oldVisibleTransactions.size() > 0 ? oldVisibleTransactions.get(0).controller : null;
+                performControllerChange(newVisibleTransactions.get(0).controller, rootController, true, handler.copy());
+
+                for (int i = oldVisibleTransactions.size() - 1; i > 0; i--) {
+                    RouterTransaction transaction = oldVisibleTransactions.get(i);
+                    ControllerChangeHandler localHandler = handler.copy();
+                    localHandler.setForceRemoveViewOnPush(true);
+                    performControllerChange(null, transaction.controller, true, localHandler);
+                }
+
+                for (int i = 1; i < newVisibleTransactions.size(); i++) {
+                    RouterTransaction transaction = newVisibleTransactions.get(i);
+                    handler = transaction.pushChangeHandler() != null ? transaction.pushChangeHandler().copy() : new SimpleSwapChangeHandler();
+                    performControllerChange(transaction.controller, newVisibleTransactions.get(i - 1).controller, true, handler.copy());
+                }
             }
         }
 
@@ -316,7 +379,7 @@ public abstract class Router {
             transaction.onAttachedToRouter();
         }
 
-        backStack.setBackstack(backstack);
+        backstack.setBackstack(newBackstack);
     }
 
     /**
@@ -350,7 +413,7 @@ public abstract class Router {
      * Attaches this Router's existing backstack to its container if one exists.
      */
     public void rebindIfNeeded() {
-        Iterator<RouterTransaction> backstackIterator = backStack.reverseIterator();
+        Iterator<RouterTransaction> backstackIterator = backstack.reverseIterator();
         while (backstackIterator.hasNext()) {
             RouterTransaction transaction = backstackIterator.next();
 
@@ -368,7 +431,7 @@ public abstract class Router {
     }
 
     public final void onActivityStarted(Activity activity) {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             transaction.controller.activityStarted(activity);
 
             for (Router childRouter : transaction.controller.getChildRouters()) {
@@ -378,7 +441,7 @@ public abstract class Router {
     }
 
     public final void onActivityResumed(Activity activity) {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             transaction.controller.activityResumed(activity);
 
             for (Router childRouter : transaction.controller.getChildRouters()) {
@@ -388,7 +451,7 @@ public abstract class Router {
     }
 
     public final void onActivityPaused(Activity activity) {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             transaction.controller.activityPaused(activity);
 
             for (Router childRouter : transaction.controller.getChildRouters()) {
@@ -398,7 +461,7 @@ public abstract class Router {
     }
 
     public final void onActivityStopped(Activity activity) {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             transaction.controller.activityStopped(activity);
 
             for (Router childRouter : transaction.controller.getChildRouters()) {
@@ -411,7 +474,7 @@ public abstract class Router {
         prepareForContainerRemoval();
         changeListeners.clear();
 
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             transaction.controller.activityDestroyed(activity.isChangingConfigurations());
 
             for (Router childRouter : transaction.controller.getChildRouters()) {
@@ -432,7 +495,10 @@ public abstract class Router {
     }
 
     public void prepareForHostDetach() {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
+            if (ControllerChangeHandler.completePushImmediately(transaction.controller.getInstanceId())) {
+                transaction.controller.setNeedsAttach();
+            }
             transaction.controller.prepareForHostDetach();
         }
     }
@@ -441,7 +507,7 @@ public abstract class Router {
         prepareForHostDetach();
 
         Bundle backstackState = new Bundle();
-        backStack.saveInstanceState(backstackState);
+        backstack.saveInstanceState(backstackState);
 
         outState.putParcelable(KEY_BACKSTACK, backstackState);
         outState.putBoolean(KEY_POPS_LAST_VIEW, popsLastView);
@@ -449,17 +515,17 @@ public abstract class Router {
 
     public void restoreInstanceState(Bundle savedInstanceState) {
         Bundle backstackBundle = savedInstanceState.getParcelable(KEY_BACKSTACK);
-        backStack.restoreInstanceState(backstackBundle);
+        backstack.restoreInstanceState(backstackBundle);
         popsLastView = savedInstanceState.getBoolean(KEY_POPS_LAST_VIEW);
 
-        Iterator<RouterTransaction> backstackIterator = backStack.reverseIterator();
+        Iterator<RouterTransaction> backstackIterator = backstack.reverseIterator();
         while (backstackIterator.hasNext()) {
             setControllerRouter(backstackIterator.next().controller);
         }
     }
 
     public final void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             transaction.controller.createOptionsMenu(menu, inflater);
 
             for (Router childRouter : transaction.controller.getChildRouters()) {
@@ -469,7 +535,7 @@ public abstract class Router {
     }
 
     public final void onPrepareOptionsMenu(Menu menu) {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             transaction.controller.prepareOptionsMenu(menu);
 
             for (Router childRouter : transaction.controller.getChildRouters()) {
@@ -479,7 +545,7 @@ public abstract class Router {
     }
 
     public final boolean onOptionsItemSelected(MenuItem item) {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             if (transaction.controller.optionsItemSelected(item)) {
                 return true;
             }
@@ -494,8 +560,8 @@ public abstract class Router {
     }
 
     private void popToTransaction(@NonNull RouterTransaction transaction, ControllerChangeHandler changeHandler) {
-        RouterTransaction topTransaction = backStack.peek();
-        List<RouterTransaction> poppedTransactions = backStack.popTo(transaction);
+        RouterTransaction topTransaction = backstack.peek();
+        List<RouterTransaction> poppedTransactions = backstack.popTo(transaction);
         trackDestroyingControllers(poppedTransactions);
 
         if (poppedTransactions.size() > 0) {
@@ -503,7 +569,7 @@ public abstract class Router {
                 changeHandler = topTransaction.popChangeHandler();
             }
 
-            performControllerChange(backStack.peek().controller, topTransaction.controller, false, changeHandler);
+            performControllerChange(backstack.peek().controller, topTransaction.controller, false, changeHandler);
         }
     }
 
@@ -516,7 +582,7 @@ public abstract class Router {
     final List<Controller> getControllers() {
         List<Controller> controllers = new ArrayList<>();
 
-        Iterator<RouterTransaction> backstackIterator = backStack.reverseIterator();
+        Iterator<RouterTransaction> backstackIterator = backstack.reverseIterator();
         while (backstackIterator.hasNext()) {
             controllers.add(backstackIterator.next().controller);
         }
@@ -525,7 +591,7 @@ public abstract class Router {
     }
 
     public final Boolean handleRequestedPermission(@NonNull String permission) {
-        for (RouterTransaction transaction : backStack) {
+        for (RouterTransaction transaction : backstack) {
             if (transaction.controller.didRequestPermission(permission)) {
                 return transaction.controller.shouldShowRequestPermissionRationale(permission);
             }
@@ -557,7 +623,7 @@ public abstract class Router {
     private void performControllerChange(final Controller to, final Controller from, boolean isPush, @NonNull ControllerChangeHandler changeHandler) {
         if (to != null) {
             setControllerRouter(to);
-        } else if (backStack.size() == 0 && !popsLastView) {
+        } else if (backstack.size() == 0 && !popsLastView) {
             // We're emptying out the backstack. Views get weird if you transition them out, so just no-op it. The hosting
             // Activity should be handling this by finishing or at least hiding this view.
             changeHandler = new NoOpControllerChangeHandler();
@@ -566,8 +632,8 @@ public abstract class Router {
         ControllerChangeHandler.executeChange(to, from, isPush, container, changeHandler, changeListeners);
     }
 
-    void pushToBackstack(@NonNull RouterTransaction entry) {
-        backStack.push(entry);
+    private void pushToBackstack(@NonNull RouterTransaction entry) {
+        backstack.push(entry);
     }
 
     private void trackDestroyingController(RouterTransaction transaction) {
@@ -589,13 +655,13 @@ public abstract class Router {
         }
     }
 
-    private void removeAllExceptTopAndUnowned() {
+    private void removeAllExceptVisibleAndUnowned() {
         List<View> views = new ArrayList<>();
 
-        RouterTransaction topTransaction = backStack.peek();
-        final View topView = topTransaction != null ? topTransaction.controller.getView() : null;
-        if (topView != null) {
-            views.add(topView);
+        for (RouterTransaction transaction : getVisibleTransactions(backstack.iterator())) {
+            if (transaction.controller.getView() != null) {
+                views.add(transaction.controller.getView());
+            }
         }
 
         for (Router router : getSiblingRouters()) {
@@ -625,6 +691,21 @@ public abstract class Router {
         }
     }
 
+    private List<RouterTransaction> getVisibleTransactions(Iterator<RouterTransaction> backstackIterator) {
+        List<RouterTransaction> transactions = new ArrayList<>();
+        while (backstackIterator.hasNext()) {
+            RouterTransaction transaction = backstackIterator.next();
+            transactions.add(transaction);
+
+            if (transaction.pushChangeHandler() == null || transaction.pushChangeHandler().removesFromViewOnPush()) {
+                break;
+            }
+        }
+
+        Collections.reverse(transactions);
+        return transactions;
+    }
+
     void setControllerRouter(Controller controller) {
         controller.setRouter(this);
     }
@@ -638,4 +719,5 @@ public abstract class Router {
     abstract void requestPermissions(String instanceId, String[] permissions, int requestCode);
     abstract boolean hasHost();
     abstract List<Router> getSiblingRouters();
+    abstract Router getRootRouter();
 }

conductor/src/main/java/com/bluelinelabs/conductor/changehandler/AnimatorChangeHandler.java

@@ -24,6 +24,7 @@ public abstract class AnimatorChangeHandler extends ControllerChangeHandler {
     private long animationDuration;
     private boolean removesFromViewOnPush;
     private boolean canceled;
+    private boolean needsImmediateCompletion;
     private Animator animator;
 
     public AnimatorChangeHandler() {
@@ -67,10 +68,21 @@ public abstract class AnimatorChangeHandler extends ControllerChangeHandler {
         }
     }
 
+    @Override
+    public void completeImmediately() {
+        super.completeImmediately();
+
+        needsImmediateCompletion = true;
+        if (animator != null) {
+            animator.cancel();
+        }
+    }
+
     public long getAnimationDuration() {
         return animationDuration;
     }
 
+    @Override
     public boolean removesFromViewOnPush() {
         return removesFromViewOnPush;
     }
@@ -99,7 +111,7 @@ public abstract class AnimatorChangeHandler extends ControllerChangeHandler {
         if (addingToView) {
             if (isPush || from == null) {
                 container.addView(to);
-            } else {
+            } else if (to.getParent() == null) {
                 container.addView(to, container.indexOfChild(from));
             }
 
@@ -124,7 +136,7 @@ public abstract class AnimatorChangeHandler extends ControllerChangeHandler {
         }
     }
 
-    private void performAnimation(@NonNull final ViewGroup container, final View from, View to, final boolean isPush, final boolean toAddedToContainer, @NonNull final ControllerChangeCompletedListener changeListener) {
+    private void performAnimation(@NonNull final ViewGroup container, final View from, final View to, final boolean isPush, final boolean toAddedToContainer, @NonNull final ControllerChangeCompletedListener changeListener) {
         if (canceled) {
             changeListener.onChangeCompleted();
             return;
@@ -139,22 +151,34 @@ public abstract class AnimatorChangeHandler extends ControllerChangeHandler {
         animator.addListener(new AnimatorListenerAdapter() {
             @Override
             public void onAnimationCancel(Animator animation) {
-                changeListener.onChangeCompleted();
-            }
-
-            @Override
-            public void onAnimationEnd(Animator animation) {
-                if (from != null && (!isPush || removesFromViewOnPush)) {
+                if (from != null && (!isPush || removesFromViewOnPush) && needsImmediateCompletion) {
                     container.removeView(from);
                 }
 
                 changeListener.onChangeCompleted();
+                animator.removeListener(this);
+                animator = null;
+            }
 
-                if (isPush && from != null) {
-                    resetFromView(from);
+            @Override
+            public void onAnimationEnd(Animator animation) {
+                if (!canceled && animator != null) {
+                    if (from != null && (!isPush || removesFromViewOnPush)) {
+                        container.removeView(from);
+                    }
+
+                    changeListener.onChangeCompleted();
+                    animator.removeListener(this);
+
+                    if (isPush && from != null) {
+                        resetFromView(from);
+                    }
+
+                    animator = null;
                 }
             }
         });
+
         animator.start();
     }
 

conductor/src/main/java/com/bluelinelabs/conductor/changehandler/SimpleSwapChangeHandler.java

@@ -3,19 +3,26 @@ package com.bluelinelabs.conductor.changehandler;
 import android.os.Bundle;
 import android.support.annotation.NonNull;
 import android.view.View;
+import android.view.View.OnAttachStateChangeListener;
 import android.view.ViewGroup;
 
+import com.bluelinelabs.conductor.Controller;
 import com.bluelinelabs.conductor.ControllerChangeHandler;
 
 /**
  * A {@link ControllerChangeHandler} that will instantly swap Views with no animations or transitions.
  */
-public class SimpleSwapChangeHandler extends ControllerChangeHandler {
+public class SimpleSwapChangeHandler extends ControllerChangeHandler implements OnAttachStateChangeListener {
 
     private static final String KEY_REMOVES_FROM_ON_PUSH = "SimpleSwapChangeHandler.removesFromViewOnPush";
 
     private boolean removesFromViewOnPush;
 
+    private boolean canceled;
+
+    private ViewGroup container;
+    private ControllerChangeCompletedListener changeListener;
+
     public SimpleSwapChangeHandler() {
         this(true);
     }
@@ -37,16 +44,61 @@ public class SimpleSwapChangeHandler extends ControllerChangeHandler {
     }
 
     @Override
-    public void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull final ControllerChangeCompletedListener changeListener) {
-        if (from != null && (!isPush || removesFromViewOnPush)) {
-            container.removeView(from);
-        }
+    public void onAbortPush(@NonNull ControllerChangeHandler newHandler, Controller newTop) {
+        super.onAbortPush(newHandler, newTop);
 
-        if (to != null && to.getParent() == null) {
-            container.addView(to);
-        }
-
-        changeListener.onChangeCompleted();
+        canceled = true;
     }
 
-}
+    @Override
+    public void completeImmediately() {
+        if (changeListener != null) {
+            changeListener.onChangeCompleted();
+            changeListener = null;
+
+            container.removeOnAttachStateChangeListener(this);
+            container = null;
+        }
+    }
+
+    @Override
+    public void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener) {
+        if (!canceled) {
+            if (from != null && (!isPush || removesFromViewOnPush)) {
+                container.removeView(from);
+            }
+
+            if (to != null && to.getParent() == null) {
+                container.addView(to);
+            }
+        }
+
+        if (container.getWindowToken() != null) {
+            changeListener.onChangeCompleted();
+        } else {
+            this.changeListener = changeListener;
+            this.container = container;
+            container.addOnAttachStateChangeListener(this);
+        }
+
+    }
+
+    @Override
+    public boolean removesFromViewOnPush() {
+        return removesFromViewOnPush;
+    }
+
+    @Override
+    public void onViewAttachedToWindow(View v) {
+        v.removeOnAttachStateChangeListener(this);
+
+        if (changeListener != null) {
+            changeListener.onChangeCompleted();
+            changeListener = null;
+            container = null;
+        }
+    }
+
+    @Override
+    public void onViewDetachedFromWindow(View v) { }
+}

conductor/src/main/java/com/bluelinelabs/conductor/changehandler/TransitionChangeHandler.java

@@ -76,4 +76,8 @@ public abstract class TransitionChangeHandler extends ControllerChangeHandler {
         }
     }
 
+    @Override
+    public final boolean removesFromViewOnPush() {
+        return true;
+    }
 }

conductor/src/main/java/com/bluelinelabs/conductor/changehandler/TransitionChangeHandlerCompat.java

@@ -77,4 +77,12 @@ public class TransitionChangeHandlerCompat extends ControllerChangeHandler {
         fallbackChangeHandler.restoreFromBundle(bundle.getBundle(KEY_FALLBACK_HANDLER_STATE));
     }
 
+    @Override
+    public boolean removesFromViewOnPush() {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+            return transitionChangeHandler.removesFromViewOnPush();
+        } else {
+            return fallbackChangeHandler.removesFromViewOnPush();
+        }
+    }
 }

conductor/src/main/java/com/bluelinelabs/conductor/internal/LifecycleHandler.java

@@ -29,6 +29,7 @@ public class LifecycleHandler extends Fragment implements ActivityLifecycleCallb
 
     private static final String KEY_PERMISSION_REQUEST_CODES = "LifecycleHandler.permissionRequests";
     private static final String KEY_ACTIVITY_REQUEST_CODES = "LifecycleHandler.activityRequests";
+    private static final String KEY_ROUTER_STATE_PREFIX = "LifecycleHandler.routerState";
 
     private Activity activity;
     private boolean hasRegisteredCallbacks;
@@ -69,7 +70,10 @@ public class LifecycleHandler extends Fragment implements ActivityLifecycleCallb
             router.setHost(this, container);
 
             if (savedInstanceState != null) {
-                router.restoreInstanceState(savedInstanceState);
+                Bundle routerSavedState = savedInstanceState.getBundle(KEY_ROUTER_STATE_PREFIX + router.getContainerId());
+                if (routerSavedState != null) {
+                    router.restoreInstanceState(routerSavedState);
+                }
             }
             routerMap.put(getRouterHashKey(container), router);
         } else {
@@ -303,7 +307,9 @@ public class LifecycleHandler extends Fragment implements ActivityLifecycleCallb
     public void onActivitySaveInstanceState(Activity activity, Bundle outState) {
         if (this.activity == activity) {
             for (Router router : routerMap.values()) {
-                router.saveInstanceState(outState);
+                Bundle bundle = new Bundle();
+                router.saveInstanceState(bundle);
+                outState.putBundle(KEY_ROUTER_STATE_PREFIX + router.getContainerId(), bundle);
             }
         }
     }

conductor/src/test/java/com/bluelinelabs/conductor/ActivityProxy.java

@@ -0,0 +1,72 @@
+package com.bluelinelabs.conductor;
+
+import android.os.Bundle;
+import android.support.annotation.IdRes;
+
+import org.robolectric.Robolectric;
+import org.robolectric.util.ActivityController;
+
+public class ActivityProxy {
+
+    private ActivityController<TestActivity> activityController;
+    private AttachFakingFrameLayout view;
+
+    public ActivityProxy() {
+        activityController = Robolectric.buildActivity(TestActivity.class);
+
+        @IdRes int containerId = 4;
+        view = new AttachFakingFrameLayout(activityController.get());
+        view.setId(containerId);
+    }
+
+    public ActivityProxy create(Bundle savedInstanceState) {
+        activityController.create(savedInstanceState);
+        return this;
+    }
+
+    public ActivityProxy start() {
+        activityController.start();
+        view.setAttached(true);
+        return this;
+    }
+
+    public ActivityProxy resume() {
+        activityController.resume();
+        return this;
+    }
+
+    public ActivityProxy pause() {
+        activityController.pause();
+        return this;
+    }
+
+    public ActivityProxy saveInstanceState(Bundle outState) {
+        activityController.saveInstanceState(outState);
+        return this;
+    }
+
+    public ActivityProxy stop() {
+        activityController.stop();
+        view.setAttached(false);
+        return this;
+    }
+
+    public ActivityProxy destroy() {
+        activityController.destroy();
+        return this;
+    }
+
+    public ActivityProxy rotate() {
+        getActivity().isChangingConfigurations = true;
+        getActivity().recreate();
+        return this;
+    }
+
+    public TestActivity getActivity() {
+        return activityController.get();
+    }
+
+    public AttachFakingFrameLayout getView() {
+        return view;
+    }
+}

conductor/src/test/java/com/bluelinelabs/conductor/AttachFakingFrameLayout.java

@@ -0,0 +1,113 @@
+package com.bluelinelabs.conductor;
+
+import android.content.Context;
+import android.os.IBinder;
+import android.os.IInterface;
+import android.os.Parcel;
+import android.os.RemoteException;
+import android.util.AttributeSet;
+import android.view.View;
+import android.widget.FrameLayout;
+
+import java.io.FileDescriptor;
+
+public class AttachFakingFrameLayout extends FrameLayout {
+
+    final IBinder fakeWindowToken = new IBinder() {
+        @Override
+        public String getInterfaceDescriptor() throws RemoteException {
+            return null;
+        }
+
+        @Override
+        public boolean pingBinder() {
+            return false;
+        }
+
+        @Override
+        public boolean isBinderAlive() {
+            return false;
+        }
+
+        @Override
+        public IInterface queryLocalInterface(String descriptor) {
+            return null;
+        }
+
+        @Override
+        public void dump(FileDescriptor fd, String[] args) throws RemoteException {
+
+        }
+
+        @Override
+        public void dumpAsync(FileDescriptor fd, String[] args) throws RemoteException {
+
+        }
+
+        @Override
+        public boolean transact(int code, Parcel data, Parcel reply, int flags) throws RemoteException {
+            return false;
+        }
+
+        @Override
+        public void linkToDeath(DeathRecipient recipient, int flags) throws RemoteException {
+
+        }
+
+        @Override
+        public boolean unlinkToDeath(DeathRecipient recipient, int flags) {
+            return false;
+        }
+    };
+
+    private boolean reportAttached;
+
+    public AttachFakingFrameLayout(Context context) {
+        super(context);
+    }
+
+    public AttachFakingFrameLayout(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    public AttachFakingFrameLayout(Context context, AttributeSet attrs, int defStyleAttr) {
+        super(context, attrs, defStyleAttr);
+    }
+
+    @Override
+    public final IBinder getWindowToken() {
+        return reportAttached ? fakeWindowToken : null;
+    }
+
+    public void setAttached(boolean attached) {
+        setAttached(attached, true);
+    }
+
+    public void setAttached(boolean attached, boolean reportToViewUtils) {
+        if (reportAttached != attached) {
+            reportAttached = attached;
+            if (reportToViewUtils) {
+                ViewUtils.reportAttached(this, attached);
+            }
+
+            for (int i = 0; i < getChildCount(); i++) {
+                ViewUtils.reportAttached(getChildAt(i), attached);
+            }
+        }
+    }
+
+    @Override
+    public void onViewAdded(View child) {
+        if (reportAttached) {
+            ViewUtils.reportAttached(child, true);
+        }
+        super.onViewAdded(child);
+    }
+
+    @Override
+    public void onViewRemoved(View child) {
+        ViewUtils.reportAttached(child, false);
+        super.onViewRemoved(child);
+    }
+
+}

conductor/src/test/java/com/bluelinelabs/conductor/CallState.java

@@ -119,9 +119,9 @@ public class CallState implements Parcelable {
                 "\n    restoreInstanceStateCalls=" + restoreInstanceStateCalls +
                 "\n    saveViewStateCalls=" + saveViewStateCalls +
                 "\n    restoreViewStateCalls=" + restoreViewStateCalls +
-                "\n    onActivityResultCalls= " + onActivityResultCalls +
-                "\n    onRequestPermissionsResultCalls= " + onRequestPermissionsResultCalls +
-                "\n    createOptionsMenuCalls= " + createOptionsMenuCalls +
+                "\n    onActivityResultCalls=" + onActivityResultCalls +
+                "\n    onRequestPermissionsResultCalls=" + onRequestPermissionsResultCalls +
+                "\n    createOptionsMenuCalls=" + createOptionsMenuCalls +
                 "}\n";
     }
 

conductor/src/test/java/com/bluelinelabs/conductor/ControllerLifecycleTests.java

@@ -1,41 +1,37 @@
 package com.bluelinelabs.conductor;
 
 import android.os.Bundle;
-import android.support.annotation.IdRes;
 import android.support.annotation.NonNull;
 import android.view.View;
 import android.view.ViewGroup;
-import android.widget.FrameLayout;
 
 import com.bluelinelabs.conductor.Controller.LifecycleListener;
-import com.bluelinelabs.conductor.ControllerChangeHandler.ControllerChangeCompletedListener;
+import com.bluelinelabs.conductor.MockChangeHandler.ChangeHandlerListener;
 
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.robolectric.Robolectric;
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.annotation.Config;
-import org.robolectric.util.ActivityController;
 
 @RunWith(RobolectricTestRunner.class)
 @Config(manifest = Config.NONE)
 public class ControllerLifecycleTests {
 
-    private ActivityController<TestActivity> activityController;
     private Router router;
 
+    private ActivityProxy activityProxy;
     private CallState currentCallState;
 
-    public void createActivityController(Bundle savedInstanceState) {
-        activityController = Robolectric.buildActivity(TestActivity.class).create(savedInstanceState).start();
+    public void createActivityController(Bundle savedInstanceState, boolean includeStartAndResume) {
+        activityProxy = new ActivityProxy().create(savedInstanceState);
 
-        @IdRes int containerId = 4;
-        FrameLayout routerContainer = new FrameLayout(activityController.get());
-        routerContainer.setId(containerId);
+        if (includeStartAndResume) {
+            activityProxy.start().resume();
+        }
 
-        router = Conductor.attachRouter(activityController.get(), routerContainer, savedInstanceState);
+        router = Conductor.attachRouter(activityProxy.getActivity(), activityProxy.getView(), savedInstanceState);
         if (!router.hasRootController()) {
             router.setRoot(RouterTransaction.with(new TestController()));
         }
@@ -43,7 +39,7 @@ public class ControllerLifecycleTests {
 
     @Before
     public void setup() {
-        createActivityController(null);
+        createActivityController(null, true);
 
         currentCallState = new CallState();
     }
@@ -82,18 +78,20 @@ public class ControllerLifecycleTests {
 
         assertCalls(expectedCallState, controller);
 
-        activityController.pause();
+        activityProxy.getActivity().isDestroying = true;
+        activityProxy.pause();
 
         assertCalls(expectedCallState, controller);
 
-        activityController.stop();
-
-        assertCalls(expectedCallState, controller);
-
-        activityController.destroy();
+        activityProxy.stop();
 
+        expectedCallState.saveViewStateCalls++;
         expectedCallState.detachCalls++;
         expectedCallState.destroyViewCalls++;
+        assertCalls(expectedCallState, controller);
+
+        activityProxy.destroy();
+
         expectedCallState.destroyCalls++;
         assertCalls(expectedCallState, controller);
     }
@@ -112,33 +110,32 @@ public class ControllerLifecycleTests {
 
         assertCalls(expectedCallState, controller);
 
-        activityController.get().isChangingConfigurations = true;
+        activityProxy.getActivity().isChangingConfigurations = true;
 
         Bundle bundle = new Bundle();
-        activityController.saveInstanceState(bundle);
+        activityProxy.saveInstanceState(bundle);
 
         expectedCallState.saveViewStateCalls++;
         expectedCallState.saveInstanceStateCalls++;
         assertCalls(expectedCallState, controller);
 
-        activityController.pause();
+        activityProxy.pause();
         assertCalls(expectedCallState, controller);
 
-        activityController.stop();
-        assertCalls(expectedCallState, controller);
-
-        activityController.destroy();
+        activityProxy.stop();
         expectedCallState.detachCalls++;
         expectedCallState.destroyViewCalls++;
         assertCalls(expectedCallState, controller);
 
-        createActivityController(bundle);
+        activityProxy.destroy();
+        assertCalls(expectedCallState, controller);
+
+        createActivityController(bundle, false);
         controller = (TestController)router.getControllerWithTag("root");
 
         expectedCallState.restoreInstanceStateCalls++;
         expectedCallState.restoreViewStateCalls++;
         expectedCallState.changeStartCalls++;
-        expectedCallState.changeEndCalls++;
         expectedCallState.createViewCalls++;
 
         // Lifecycle listener isn't attached during restore, grab the current views from the controller for this stuff...
@@ -147,10 +144,19 @@ public class ControllerLifecycleTests {
         currentCallState.changeStartCalls = controller.currentCallState.changeStartCalls;
         currentCallState.changeEndCalls = controller.currentCallState.changeEndCalls;
         currentCallState.createViewCalls = controller.currentCallState.createViewCalls;
+        currentCallState.attachCalls = controller.currentCallState.attachCalls;
 
         assertCalls(expectedCallState, controller);
 
-        activityController.resume();
+        activityProxy.start().resume();
+        currentCallState.changeEndCalls = controller.currentCallState.changeEndCalls;
+        currentCallState.attachCalls = controller.currentCallState.attachCalls;
+        expectedCallState.changeEndCalls++;
+        expectedCallState.attachCalls++;
+
+        assertCalls(expectedCallState, controller);
+
+        activityProxy.resume();
         assertCalls(expectedCallState, controller);
     }
 
@@ -167,16 +173,16 @@ public class ControllerLifecycleTests {
 
         assertCalls(expectedCallState, controller);
 
-        activityController.pause();
+        activityProxy.pause();
 
         Bundle bundle = new Bundle();
-        activityController.saveInstanceState(bundle);
+        activityProxy.saveInstanceState(bundle);
 
         expectedCallState.saveInstanceStateCalls++;
         expectedCallState.saveViewStateCalls++;
         assertCalls(expectedCallState, controller);
 
-        activityController.resume();
+        activityProxy.resume();
     }
 
     @Test
@@ -377,22 +383,8 @@ public class ControllerLifecycleTests {
         });
 
         router.pushController(RouterTransaction.with(testController)
-                .pushChangeHandler(new ChangeHandler(new ChangeHandlerListener() {
-                    @Override
-                    public void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener) {
-                        container.addView(to);
-                        ViewUtils.setAttached(to, true);
-                        changeListener.onChangeCompleted();
-                    }
-                }))
-                .popChangeHandler(new ChangeHandler(new ChangeHandlerListener() {
-                    @Override
-                    public void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener) {
-                        container.removeView(from);
-                        ViewUtils.setAttached(from, false);
-                        changeListener.onChangeCompleted();
-                    }
-                })));
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
 
         router.popController(testController);
 
@@ -407,14 +399,7 @@ public class ControllerLifecycleTests {
     public void testChildLifecycle() {
         Controller parent = new TestController();
         router.pushController(RouterTransaction.with(parent)
-                .pushChangeHandler(new ChangeHandler(new ChangeHandlerListener() {
-                    @Override
-                    public void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener) {
-                        container.addView(to);
-                        ViewUtils.setAttached(to, true);
-                        changeListener.onChangeCompleted();
-                    }
-                })));
+                .pushChangeHandler(new MockChangeHandler()));
 
         TestController child = new TestController();
         attachLifecycleListener(child);
@@ -440,22 +425,8 @@ public class ControllerLifecycleTests {
     public void testChildLifecycle2() {
         Controller parent = new TestController();
         router.pushController(RouterTransaction.with(parent)
-                .pushChangeHandler(new ChangeHandler(new ChangeHandlerListener() {
-                    @Override
-                    public void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener) {
-                        container.addView(to);
-                        ViewUtils.setAttached(to, true);
-                        changeListener.onChangeCompleted();
-                    }
-                }))
-                .popChangeHandler(new ChangeHandler(new ChangeHandlerListener() {
-                    @Override
-                    public void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener) {
-                        container.removeView(from);
-                        ViewUtils.setAttached(from, false);
-                        changeListener.onChangeCompleted();
-                    }
-                })));
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
 
         TestController child = new TestController();
         attachLifecycleListener(child);
@@ -477,44 +448,47 @@ public class ControllerLifecycleTests {
         assertCalls(expectedCallState, child);
     }
 
-    private ChangeHandler getPushHandler(final CallState expectedCallState, final TestController controller) {
-        return new ChangeHandler(new ChangeHandlerListener() {
+    private MockChangeHandler getPushHandler(final CallState expectedCallState, final TestController controller) {
+        return new MockChangeHandler(new ChangeHandlerListener() {
             @Override
-            public void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener) {
+            void willStartChange() {
                 expectedCallState.changeStartCalls++;
                 expectedCallState.createViewCalls++;
                 assertCalls(expectedCallState, controller);
+            }
 
-                container.addView(to);
-                ViewUtils.setAttached(to, true);
-
+            @Override
+            void didAttachOrDetach() {
                 expectedCallState.attachCalls++;
                 assertCalls(expectedCallState, controller);
+            }
 
-                changeListener.onChangeCompleted();
-
+            @Override
+            void didEndChange() {
                 expectedCallState.changeEndCalls++;
                 assertCalls(expectedCallState, controller);
             }
         });
     }
 
-    private ChangeHandler getPopHandler(final CallState expectedCallState, final TestController controller) {
-        return new ChangeHandler(new ChangeHandlerListener() {
+    private MockChangeHandler getPopHandler(final CallState expectedCallState, final TestController controller) {
+        return new MockChangeHandler(new ChangeHandlerListener() {
             @Override
-            public void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener) {
+            void willStartChange() {
                 expectedCallState.changeStartCalls++;
                 assertCalls(expectedCallState, controller);
-                container.removeView(from);
-                ViewUtils.setAttached(from, false);
+            }
 
+            @Override
+            void didAttachOrDetach() {
                 expectedCallState.destroyViewCalls++;
                 expectedCallState.detachCalls++;
                 expectedCallState.destroyCalls++;
                 assertCalls(expectedCallState, controller);
+            }
 
-                changeListener.onChangeCompleted();
-
+            @Override
+            void didEndChange() {
                 expectedCallState.changeEndCalls++;
                 assertCalls(expectedCallState, controller);
             }
@@ -585,24 +559,4 @@ public class ControllerLifecycleTests {
         });
     }
 
-    interface ChangeHandlerListener {
-        void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener);
-    }
-
-    public static class ChangeHandler extends ControllerChangeHandler {
-
-        private ChangeHandlerListener listener;
-
-        public ChangeHandler() { }
-
-        public ChangeHandler(ChangeHandlerListener listener) {
-            this.listener = listener;
-        }
-
-        @Override
-        public void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener) {
-            listener.performChange(container, from, to, isPush, changeListener);
-        }
-    }
-
 }

conductor/src/test/java/com/bluelinelabs/conductor/ControllerTests.java

@@ -3,10 +3,8 @@ package com.bluelinelabs.conductor;
 import android.app.Activity;
 import android.content.Intent;
 import android.os.Bundle;
-import android.support.annotation.IdRes;
 import android.view.View;
 import android.view.ViewGroup;
-import android.widget.FrameLayout;
 
 import com.bluelinelabs.conductor.Controller.RetainViewMode;
 
@@ -14,26 +12,19 @@ import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.robolectric.Robolectric;
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.annotation.Config;
-import org.robolectric.util.ActivityController;
 
 @RunWith(RobolectricTestRunner.class)
 @Config(manifest = Config.NONE)
 public class ControllerTests {
 
-    private ActivityController<TestActivity> activityController;
+    private ActivityProxy activityProxy;
     private Router router;
 
     public void createActivityController(Bundle savedInstanceState) {
-        activityController = Robolectric.buildActivity(TestActivity.class).create(savedInstanceState).start();
-
-        @IdRes int containerId = 4;
-        FrameLayout routerContainer = new FrameLayout(activityController.get());
-        routerContainer.setId(containerId);
-
-        router = Conductor.attachRouter(activityController.get(), routerContainer, savedInstanceState);
+        activityProxy = new ActivityProxy().create(savedInstanceState).start().resume();
+        router = Conductor.attachRouter(activityProxy.getActivity(), activityProxy.getView(), savedInstanceState);
         if (!router.hasRootController()) {
             router.setRoot(RouterTransaction.with(new TestController()));
         }
@@ -51,20 +42,20 @@ public class ControllerTests {
         // Test View getting released w/ RELEASE_DETACH
         controller.setRetainViewMode(RetainViewMode.RELEASE_DETACH);
         Assert.assertNull(controller.getView());
-        View view = controller.inflate(new FrameLayout(router.getActivity()));
+        View view = controller.inflate(new AttachFakingFrameLayout(router.getActivity()));
         Assert.assertNotNull(controller.getView());
-        ViewUtils.setAttached(view, true);
+        ViewUtils.reportAttached(view, true);
         Assert.assertNotNull(controller.getView());
-        ViewUtils.setAttached(view, false);
+        ViewUtils.reportAttached(view, false);
         Assert.assertNull(controller.getView());
 
         // Test View getting retained w/ RETAIN_DETACH
         controller.setRetainViewMode(RetainViewMode.RETAIN_DETACH);
-        view = controller.inflate(new FrameLayout(router.getActivity()));
+        view = controller.inflate(new AttachFakingFrameLayout(router.getActivity()));
         Assert.assertNotNull(controller.getView());
-        ViewUtils.setAttached(view, true);
+        ViewUtils.reportAttached(view, true);
         Assert.assertNotNull(controller.getView());
-        ViewUtils.setAttached(view, false);
+        ViewUtils.reportAttached(view, false);
         Assert.assertNotNull(controller.getView());
 
         // Ensure re-setting RELEASE_DETACH releases
@@ -78,7 +69,6 @@ public class ControllerTests {
         CallState expectedCallState = new CallState(true);
 
         router.pushController(RouterTransaction.with(controller));
-        ViewUtils.setAttached(controller.getView(), true);
 
         // Ensure that calling onActivityResult w/o requesting a result doesn't do anything
         router.onActivityResult(1, Activity.RESULT_OK, null);
@@ -103,10 +93,8 @@ public class ControllerTests {
         TestController child = new TestController();
 
         router.pushController(RouterTransaction.with(parent));
-        ViewUtils.setAttached(parent.getView(), true);
         parent.getChildRouter((ViewGroup)parent.getView().findViewById(TestController.VIEW_ID), null)
                 .setRoot(RouterTransaction.with(child));
-        ViewUtils.setAttached(child.getView(), true);
 
         CallState childExpectedCallState = new CallState(true);
         CallState parentExpectedCallState = new CallState(true);
@@ -139,7 +127,6 @@ public class ControllerTests {
         CallState expectedCallState = new CallState(true);
 
         router.pushController(RouterTransaction.with(controller));
-        ViewUtils.setAttached(controller.getView(), true);
 
         // Ensure that calling handleRequestedPermission w/o requesting a result doesn't do anything
         router.onRequestPermissionsResult("anotherId", 1, requestedPermissions, new int[] {1});
@@ -163,10 +150,8 @@ public class ControllerTests {
         TestController child = new TestController();
 
         router.pushController(RouterTransaction.with(parent));
-        ViewUtils.setAttached(parent.getView(), true);
         parent.getChildRouter((ViewGroup)parent.getView().findViewById(TestController.VIEW_ID), null)
                 .setRoot(RouterTransaction.with(child));
-        ViewUtils.setAttached(child.getView(), true);
 
         CallState childExpectedCallState = new CallState(true);
         CallState parentExpectedCallState = new CallState(true);
@@ -193,7 +178,6 @@ public class ControllerTests {
         CallState expectedCallState = new CallState(true);
 
         router.pushController(RouterTransaction.with(controller));
-        ViewUtils.setAttached(controller.getView(), true);
 
         // Ensure that calling onCreateOptionsMenu w/o declaring that we have one doesn't do anything
         router.onCreateOptionsMenu(null, null);
@@ -230,10 +214,8 @@ public class ControllerTests {
         TestController child = new TestController();
 
         router.pushController(RouterTransaction.with(parent));
-        ViewUtils.setAttached(parent.getView(), true);
         parent.getChildRouter((ViewGroup)parent.getView().findViewById(TestController.VIEW_ID), null)
                 .setRoot(RouterTransaction.with(child));
-        ViewUtils.setAttached(child.getView(), true);
 
         CallState childExpectedCallState = new CallState(true);
         CallState parentExpectedCallState = new CallState(true);
@@ -285,6 +267,7 @@ public class ControllerTests {
         Assert.assertNull(child2.getParentController());
 
         Router childRouter = parent.getChildRouter((ViewGroup)parent.getView().findViewById(TestController.VIEW_ID), null);
+        childRouter.setPopsLastView(true);
         childRouter.setRoot(RouterTransaction.with(child1));
 
         Assert.assertEquals(1, parent.getChildRouters().size());

conductor/src/test/java/com/bluelinelabs/conductor/MockChangeHandler.java

@@ -0,0 +1,85 @@
+package com.bluelinelabs.conductor;
+
+
+import android.os.Bundle;
+import android.support.annotation.NonNull;
+import android.view.View;
+import android.view.ViewGroup;
+
+public class MockChangeHandler extends ControllerChangeHandler {
+
+    private static final String KEY_REMOVES_FROM_VIEW_ON_PUSH = "MockChangeHandler.removesFromViewOnPush";
+
+    static class ChangeHandlerListener {
+        void willStartChange() { }
+        void didAttachOrDetach() { }
+        void didEndChange() { }
+    }
+
+    final ChangeHandlerListener listener;
+    boolean removesFromViewOnPush;
+
+    public MockChangeHandler() {
+        this(true, null);
+    }
+
+    public MockChangeHandler(boolean removesViewOnPush) {
+        this(removesViewOnPush, null);
+    }
+
+    public MockChangeHandler(@NonNull ChangeHandlerListener listener) {
+        this(true, listener);
+    }
+
+    public MockChangeHandler(boolean removesFromViewOnPush, ChangeHandlerListener listener) {
+        this.removesFromViewOnPush = removesFromViewOnPush;
+
+        if (listener == null) {
+            this.listener = new ChangeHandlerListener() { };
+        } else {
+            this.listener = listener;
+        }
+    }
+
+    @Override
+    public void performChange(@NonNull ViewGroup container, View from, View to, boolean isPush, @NonNull ControllerChangeCompletedListener changeListener) {
+        listener.willStartChange();
+
+        if (isPush) {
+            container.addView(to);
+            listener.didAttachOrDetach();
+
+            if (removesFromViewOnPush && from != null) {
+                container.removeView(from);
+            }
+        } else {
+            container.removeView(from);
+            listener.didAttachOrDetach();
+
+            if (to != null) {
+                container.addView(to);
+            }
+
+        }
+
+        changeListener.onChangeCompleted();
+        listener.didEndChange();
+    }
+
+    @Override
+    public boolean removesFromViewOnPush() {
+        return removesFromViewOnPush;
+    }
+
+    @Override
+    public void saveToBundle(@NonNull Bundle bundle) {
+        super.saveToBundle(bundle);
+        bundle.putBoolean(KEY_REMOVES_FROM_VIEW_ON_PUSH, removesFromViewOnPush);
+    }
+
+    @Override
+    public void restoreFromBundle(@NonNull Bundle bundle) {
+        super.restoreFromBundle(bundle);
+        removesFromViewOnPush = bundle.getBoolean(KEY_REMOVES_FROM_VIEW_ON_PUSH);
+    }
+}

conductor/src/test/java/com/bluelinelabs/conductor/ReattachCaseTests.java

@@ -0,0 +1,234 @@
+package com.bluelinelabs.conductor;
+
+import android.os.Bundle;
+import android.view.ViewGroup;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.annotation.Config;
+
+@RunWith(RobolectricTestRunner.class)
+@Config(manifest = Config.NONE)
+public class ReattachCaseTests {
+
+    private ActivityProxy activityProxy;
+    private Router router;
+
+    public void createActivityController(Bundle savedInstanceState) {
+        activityProxy = new ActivityProxy().create(savedInstanceState).start().resume();
+        router = Conductor.attachRouter(activityProxy.getActivity(), activityProxy.getView(), savedInstanceState);
+        if (!router.hasRootController()) {
+            router.setRoot(RouterTransaction.with(new TestController()));
+        }
+    }
+
+    @Before
+    public void setup() {
+        createActivityController(null);
+    }
+
+    @Test
+    public void testNeedsAttachingOnPauseAndOrientation() {
+        final TestController controllerA = new TestController();
+        final TestController controllerB = new TestController();
+
+        router.pushController(RouterTransaction.with(controllerA)
+            .pushChangeHandler(new MockChangeHandler())
+            .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertTrue(controllerA.isAttached());
+        Assert.assertFalse(controllerB.isAttached());
+
+        sleepWakeDevice();
+
+        Assert.assertTrue(controllerA.isAttached());
+        Assert.assertFalse(controllerB.isAttached());
+
+        router.pushController(RouterTransaction.with(controllerB)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+
+        activityProxy.rotate();
+        router.rebindIfNeeded();
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+    }
+
+    @Test
+    public void testChildNeedsAttachOnPauseAndOrientation() {
+        final TestController controllerA = new TestController();
+        final TestController childController = new TestController();
+        final TestController controllerB = new TestController();
+
+        router.pushController(RouterTransaction.with(controllerA)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Router childRouter = controllerA.getChildRouter((ViewGroup)controllerA.getView().findViewById(TestController.VIEW_ID), null);
+        childRouter.pushController(RouterTransaction.with(childController)
+            .pushChangeHandler(new MockChangeHandler())
+            .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertTrue(controllerA.isAttached());
+        Assert.assertTrue(childController.isAttached());
+        Assert.assertFalse(controllerB.isAttached());
+
+        sleepWakeDevice();
+
+        Assert.assertTrue(controllerA.isAttached());
+        Assert.assertTrue(childController.isAttached());
+        Assert.assertFalse(controllerB.isAttached());
+
+        router.pushController(RouterTransaction.with(controllerB)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertFalse(childController.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+
+        activityProxy.rotate();
+        router.rebindIfNeeded();
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertFalse(childController.isAttached());
+        Assert.assertTrue(childController.getNeedsAttach());
+        Assert.assertTrue(controllerB.isAttached());
+    }
+
+    @Test
+    public void testChildHandleBackOnOrientation() {
+        final TestController controllerA = new TestController();
+        final TestController controllerB = new TestController();
+        final TestController childController = new TestController();
+
+        router.pushController(RouterTransaction.with(controllerA)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertTrue(controllerA.isAttached());
+        Assert.assertFalse(controllerB.isAttached());
+        Assert.assertFalse(childController.isAttached());
+
+        router.pushController(RouterTransaction.with(controllerB)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Router childRouter = controllerB.getChildRouter((ViewGroup)controllerB.getView().findViewById(TestController.VIEW_ID), null);
+        childRouter.setPopsLastView(true);
+        childRouter.pushController(RouterTransaction.with(childController)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+        Assert.assertTrue(childController.isAttached());
+
+        activityProxy.rotate();
+        router.rebindIfNeeded();
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+        Assert.assertTrue(childController.isAttached());
+
+        router.handleBack();
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+        Assert.assertFalse(childController.isAttached());
+
+        router.handleBack();
+
+        Assert.assertTrue(controllerA.isAttached());
+        Assert.assertFalse(controllerB.isAttached());
+        Assert.assertFalse(childController.isAttached());
+    }
+
+    // Attempt to test https://github.com/bluelinelabs/Conductor/issues/86#issuecomment-231381271
+    @Test
+    public void testReusedChildRouterHandleBackOnOrientation() {
+        TestController controllerA = new TestController();
+        TestController controllerB = new TestController();
+        TestController childController = new TestController();
+
+        router.pushController(RouterTransaction.with(controllerA)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertTrue(controllerA.isAttached());
+        Assert.assertFalse(controllerB.isAttached());
+        Assert.assertFalse(childController.isAttached());
+
+        router.pushController(RouterTransaction.with(controllerB)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Router childRouter = controllerB.getChildRouter((ViewGroup)controllerB.getView().findViewById(TestController.VIEW_ID), null);
+        childRouter.setPopsLastView(true);
+        childRouter.pushController(RouterTransaction.with(childController)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+        Assert.assertTrue(childController.isAttached());
+
+        router.handleBack();
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+        Assert.assertFalse(childController.isAttached());
+
+        childController = new TestController();
+        childRouter.pushController(RouterTransaction.with(childController)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+        Assert.assertTrue(childController.isAttached());
+
+        activityProxy.rotate();
+        router.rebindIfNeeded();
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+        Assert.assertTrue(childController.isAttached());
+
+        router.handleBack();
+
+        childController = new TestController();
+        childRouter.pushController(RouterTransaction.with(childController)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+        Assert.assertTrue(childController.isAttached());
+
+        router.handleBack();
+
+        Assert.assertFalse(controllerA.isAttached());
+        Assert.assertTrue(controllerB.isAttached());
+        Assert.assertFalse(childController.isAttached());
+
+        router.handleBack();
+
+        Assert.assertTrue(controllerA.isAttached());
+        Assert.assertFalse(controllerB.isAttached());
+        Assert.assertFalse(childController.isAttached());
+    }
+
+    private void sleepWakeDevice() {
+        activityProxy.saveInstanceState(new Bundle()).pause();
+        activityProxy.resume();
+    }
+
+}

conductor/src/test/java/com/bluelinelabs/conductor/RouterTests.java

@@ -1,16 +1,15 @@
 package com.bluelinelabs.conductor;
 
-import android.app.Activity;
-import android.widget.FrameLayout;
-
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.robolectric.Robolectric;
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.annotation.Config;
 
+import java.util.ArrayList;
+import java.util.List;
+
 @RunWith(RobolectricTestRunner.class)
 @Config(manifest = Config.NONE)
 public class RouterTests {
@@ -19,8 +18,8 @@ public class RouterTests {
 
     @Before
     public void setup() {
-        Activity activity = Robolectric.buildActivity(TestActivity.class).create().get();
-        router = Conductor.attachRouter(activity, new FrameLayout(activity), null);
+        ActivityProxy activityProxy = new ActivityProxy().create(null).start().resume();
+        router = Conductor.attachRouter(activityProxy.getActivity(), activityProxy.getView(), null);
     }
 
     @Test
@@ -174,4 +173,149 @@ public class RouterTests {
         Assert.assertEquals(controller3, router.getControllerWithTag(controller3Tag));
     }
 
+    @Test
+    public void testSetBackstack() {
+        RouterTransaction rootTransaction = RouterTransaction.with(new TestController());
+        RouterTransaction middleTransaction = RouterTransaction.with(new TestController());
+        RouterTransaction topTransaction = RouterTransaction.with(new TestController());
+
+        List<RouterTransaction> backstack = new ArrayList<>();
+        backstack.add(rootTransaction);
+        backstack.add(middleTransaction);
+        backstack.add(topTransaction);
+
+        router.setBackstack(backstack, null);
+
+        Assert.assertEquals(3, router.getBackstackSize());
+
+        List<RouterTransaction> fetchedBackstack = router.getBackstack();
+        Assert.assertEquals(rootTransaction, fetchedBackstack.get(0));
+        Assert.assertEquals(middleTransaction, fetchedBackstack.get(1));
+        Assert.assertEquals(topTransaction, fetchedBackstack.get(2));
+    }
+
+    @Test
+    public void testNewSetBackstack() {
+        router.setRoot(RouterTransaction.with(new TestController()));
+
+        Assert.assertEquals(1, router.getBackstackSize());
+
+        RouterTransaction rootTransaction = RouterTransaction.with(new TestController());
+        RouterTransaction middleTransaction = RouterTransaction.with(new TestController());
+        RouterTransaction topTransaction = RouterTransaction.with(new TestController());
+
+        List<RouterTransaction> backstack = new ArrayList<>();
+        backstack.add(rootTransaction);
+        backstack.add(middleTransaction);
+        backstack.add(topTransaction);
+
+        router.setBackstack(backstack, null);
+
+        Assert.assertEquals(3, router.getBackstackSize());
+
+        List<RouterTransaction> fetchedBackstack = router.getBackstack();
+        Assert.assertEquals(rootTransaction, fetchedBackstack.get(0));
+        Assert.assertEquals(middleTransaction, fetchedBackstack.get(1));
+        Assert.assertEquals(topTransaction, fetchedBackstack.get(2));
+    }
+
+    @Test
+    public void testNewSetBackstackWithNoRemoveViewOnPush() {
+        RouterTransaction oldRootTransaction = RouterTransaction.with(new TestController());
+        RouterTransaction oldTopTransaction = RouterTransaction.with(new TestController()).pushChangeHandler(new MockChangeHandler(false));
+
+        router.setRoot(oldRootTransaction);
+        router.pushController(oldTopTransaction);
+        Assert.assertEquals(2, router.getBackstackSize());
+
+        Assert.assertTrue(oldRootTransaction.controller.isAttached());
+        Assert.assertTrue(oldTopTransaction.controller.isAttached());
+
+        RouterTransaction rootTransaction = RouterTransaction.with(new TestController());
+        RouterTransaction middleTransaction = RouterTransaction.with(new TestController()).pushChangeHandler(new MockChangeHandler(false));
+        RouterTransaction topTransaction = RouterTransaction.with(new TestController()).pushChangeHandler(new MockChangeHandler(false));
+
+        List<RouterTransaction> backstack = new ArrayList<>();
+        backstack.add(rootTransaction);
+        backstack.add(middleTransaction);
+        backstack.add(topTransaction);
+
+        router.setBackstack(backstack, null);
+
+        Assert.assertEquals(3, router.getBackstackSize());
+
+        List<RouterTransaction> fetchedBackstack = router.getBackstack();
+        Assert.assertEquals(rootTransaction, fetchedBackstack.get(0));
+        Assert.assertEquals(middleTransaction, fetchedBackstack.get(1));
+        Assert.assertEquals(topTransaction, fetchedBackstack.get(2));
+
+        Assert.assertFalse(oldRootTransaction.controller.isAttached());
+        Assert.assertFalse(oldTopTransaction.controller.isAttached());
+        Assert.assertTrue(rootTransaction.controller.isAttached());
+        Assert.assertTrue(middleTransaction.controller.isAttached());
+        Assert.assertTrue(topTransaction.controller.isAttached());
+    }
+
+    @Test
+    public void testReplaceTopController() {
+        RouterTransaction rootTransaction = RouterTransaction.with(new TestController());
+        RouterTransaction topTransaction = RouterTransaction.with(new TestController());
+
+        List<RouterTransaction> backstack = new ArrayList<>();
+        backstack.add(rootTransaction);
+        backstack.add(topTransaction);
+
+        router.setBackstack(backstack, null);
+
+        Assert.assertEquals(2, router.getBackstackSize());
+
+        List<RouterTransaction> fetchedBackstack = router.getBackstack();
+        Assert.assertEquals(rootTransaction, fetchedBackstack.get(0));
+        Assert.assertEquals(topTransaction, fetchedBackstack.get(1));
+
+        RouterTransaction newTopTransaction = RouterTransaction.with(new TestController());
+        router.replaceTopController(newTopTransaction);
+
+        Assert.assertEquals(2, router.getBackstackSize());
+
+        fetchedBackstack = router.getBackstack();
+        Assert.assertEquals(rootTransaction, fetchedBackstack.get(0));
+        Assert.assertEquals(newTopTransaction, fetchedBackstack.get(1));
+    }
+
+    @Test
+    public void testReplaceTopControllerWithNoRemoveViewOnPush() {
+        RouterTransaction rootTransaction = RouterTransaction.with(new TestController());
+        RouterTransaction topTransaction = RouterTransaction.with(new TestController()).pushChangeHandler(new MockChangeHandler(false));
+
+        List<RouterTransaction> backstack = new ArrayList<>();
+        backstack.add(rootTransaction);
+        backstack.add(topTransaction);
+
+        router.setBackstack(backstack, null);
+
+        Assert.assertEquals(2, router.getBackstackSize());
+
+        Assert.assertTrue(rootTransaction.controller.isAttached());
+        Assert.assertTrue(topTransaction.controller.isAttached());
+
+        List<RouterTransaction> fetchedBackstack = router.getBackstack();
+        Assert.assertEquals(rootTransaction, fetchedBackstack.get(0));
+        Assert.assertEquals(topTransaction, fetchedBackstack.get(1));
+
+        RouterTransaction newTopTransaction = RouterTransaction.with(new TestController()).pushChangeHandler(new MockChangeHandler(false));
+        router.replaceTopController(newTopTransaction);
+        newTopTransaction.pushChangeHandler().completeImmediately();
+
+        Assert.assertEquals(2, router.getBackstackSize());
+
+        fetchedBackstack = router.getBackstack();
+        Assert.assertEquals(rootTransaction, fetchedBackstack.get(0));
+        Assert.assertEquals(newTopTransaction, fetchedBackstack.get(1));
+
+        Assert.assertTrue(rootTransaction.controller.isAttached());
+        Assert.assertFalse(topTransaction.controller.isAttached());
+        Assert.assertTrue(newTopTransaction.controller.isAttached());
+    }
+
 }

conductor/src/test/java/com/bluelinelabs/conductor/TargetControllerTests.java

@@ -0,0 +1,100 @@
+package com.bluelinelabs.conductor;
+
+import android.os.Bundle;
+import android.view.ViewGroup;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.annotation.Config;
+
+@RunWith(RobolectricTestRunner.class)
+@Config(manifest = Config.NONE)
+public class TargetControllerTests {
+
+    private Router router;
+
+    public void createActivityController(Bundle savedInstanceState) {
+        ActivityProxy activityProxy = new ActivityProxy().create(savedInstanceState).start().resume();
+        router = Conductor.attachRouter(activityProxy.getActivity(), activityProxy.getView(), savedInstanceState);
+        if (!router.hasRootController()) {
+            router.setRoot(RouterTransaction.with(new TestController()));
+        }
+    }
+
+    @Before
+    public void setup() {
+        createActivityController(null);
+    }
+
+    @Test
+    public void testSiblingTarget() {
+        final TestController controllerA = new TestController();
+        final TestController controllerB = new TestController();
+
+        Assert.assertNull(controllerA.getTargetController());
+        Assert.assertNull(controllerB.getTargetController());
+
+        router.pushController(RouterTransaction.with(controllerA)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        controllerB.setTargetController(controllerA);
+
+        router.pushController(RouterTransaction.with(controllerB)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertNull(controllerA.getTargetController());
+        Assert.assertEquals(controllerA, controllerB.getTargetController());
+    }
+
+    @Test
+    public void testParentChildTarget() {
+        final TestController controllerA = new TestController();
+        final TestController controllerB = new TestController();
+
+        Assert.assertNull(controllerA.getTargetController());
+        Assert.assertNull(controllerB.getTargetController());
+
+        router.pushController(RouterTransaction.with(controllerA)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        controllerB.setTargetController(controllerA);
+
+        Router childRouter = controllerA.getChildRouter((ViewGroup)controllerA.getView().findViewById(TestController.VIEW_ID), null);
+        childRouter.pushController(RouterTransaction.with(controllerB)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertNull(controllerA.getTargetController());
+        Assert.assertEquals(controllerA, controllerB.getTargetController());
+    }
+
+    @Test
+    public void testChildParentTarget() {
+        final TestController controllerA = new TestController();
+        final TestController controllerB = new TestController();
+
+        Assert.assertNull(controllerA.getTargetController());
+        Assert.assertNull(controllerB.getTargetController());
+
+        router.pushController(RouterTransaction.with(controllerA)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        controllerA.setTargetController(controllerB);
+
+        Router childRouter = controllerA.getChildRouter((ViewGroup)controllerA.getView().findViewById(TestController.VIEW_ID), null);
+        childRouter.pushController(RouterTransaction.with(controllerB)
+                .pushChangeHandler(new MockChangeHandler())
+                .popChangeHandler(new MockChangeHandler()));
+
+        Assert.assertNull(controllerB.getTargetController());
+        Assert.assertEquals(controllerB, controllerA.getTargetController());
+    }
+
+}

conductor/src/test/java/com/bluelinelabs/conductor/TestActivity.java

@@ -5,10 +5,15 @@ import android.app.Activity;
 public class TestActivity extends Activity {
 
     public boolean isChangingConfigurations = false;
+    public boolean isDestroying = false;
 
     @Override
     public boolean isChangingConfigurations() {
         return isChangingConfigurations;
     }
 
+    @Override
+    public boolean isDestroyed() {
+        return isDestroying || super.isDestroyed();
+    }
 }

conductor/src/test/java/com/bluelinelabs/conductor/TestController.java

@@ -29,7 +29,7 @@ public class TestController extends Controller {
     @Override
     protected View onCreateView(@NonNull LayoutInflater inflater, @NonNull ViewGroup container) {
         currentCallState.createViewCalls++;
-        FrameLayout view = new FrameLayout(inflater.getContext());
+        FrameLayout view = new AttachFakingFrameLayout(inflater.getContext());
         view.setId(VIEW_ID);
 
         FrameLayout childContainer1 = new FrameLayout(inflater.getContext());

conductor/src/test/java/com/bluelinelabs/conductor/ViewUtils.java

@@ -9,9 +9,26 @@ import java.util.List;
 
 public class ViewUtils {
 
-    static void setAttached(View view, boolean attached) {
-        Object listenerInfo = ReflectionHelpers.callInstanceMethod(view, "getListenerInfo");
-        List<OnAttachStateChangeListener> listeners = ReflectionHelpers.getField(listenerInfo, "mOnAttachStateChangeListeners");
+    public static void reportAttached(View view, boolean attached) {
+        if (view instanceof AttachFakingFrameLayout) {
+            ((AttachFakingFrameLayout)view).setAttached(attached, false);
+        }
+
+        List<OnAttachStateChangeListener> listeners = getAttachStateListeners(view);
+
+        // Add, then remove an OnAttachStateChangeListener to initialize the attachStateListeners variable inside a view
+        if (listeners == null) {
+            OnAttachStateChangeListener tmpListener = new OnAttachStateChangeListener() {
+                @Override
+                public void onViewAttachedToWindow(View v) { }
+
+                @Override
+                public void onViewDetachedFromWindow(View v) { }
+            };
+            view.addOnAttachStateChangeListener(tmpListener);
+            view.removeOnAttachStateChangeListener(tmpListener);
+            listeners = getAttachStateListeners(view);
+        }
 
         for (OnAttachStateChangeListener listener : listeners) {
             if (attached) {
@@ -20,6 +37,12 @@ public class ViewUtils {
                 listener.onViewDetachedFromWindow(view);
             }
         }
+
+    }
+
+    private static List<OnAttachStateChangeListener> getAttachStateListeners(View view) {
+        Object listenerInfo = ReflectionHelpers.callInstanceMethod(view, "getListenerInfo");
+        return ReflectionHelpers.getField(listenerInfo, "mOnAttachStateChangeListeners");
     }
 
 }

demo/src/main/java/com/bluelinelabs/conductor/demo/MainActivity.java

@@ -12,22 +12,20 @@ import com.bluelinelabs.conductor.demo.controllers.HomeController;
 
 import butterknife.BindView;
 import butterknife.ButterKnife;
-import butterknife.Unbinder;
 
-public class MainActivity extends AppCompatActivity implements ActionBarProvider {
+public final class MainActivity extends AppCompatActivity implements ActionBarProvider {
 
     @BindView(R.id.toolbar) Toolbar toolbar;
     @BindView(R.id.controller_container) ViewGroup container;
 
     private Router router;
-    private Unbinder unbinder;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
         setContentView(R.layout.activity_main);
-        unbinder = ButterKnife.bind(this);
+        ButterKnife.bind(this);
 
         setSupportActionBar(toolbar);
 
@@ -44,10 +42,4 @@ public class MainActivity extends AppCompatActivity implements ActionBarProvider
         }
     }
 
-    @Override
-    protected void onDestroy() {
-        super.onDestroy();
-        unbinder.unbind();
-    }
-
 }

demo/src/main/java/com/bluelinelabs/conductor/demo/controllers/ParentController.java

@@ -16,10 +16,13 @@ import com.bluelinelabs.conductor.demo.R;
 import com.bluelinelabs.conductor.demo.controllers.base.BaseController;
 import com.bluelinelabs.conductor.demo.util.ColorUtil;
 
+import java.util.List;
+
 public class ParentController extends BaseController {
 
     private static final int NUMBER_OF_CHILDREN = 5;
     private boolean finishing;
+    private boolean hasShownAll;
 
     @NonNull
     @Override
@@ -47,8 +50,12 @@ public class ParentController extends BaseController {
             childController.addLifecycleListener(new LifecycleListener() {
                 @Override
                 public void onChangeEnd(@NonNull Controller controller, @NonNull ControllerChangeHandler changeHandler, @NonNull ControllerChangeType changeType) {
-                    if (changeType == ControllerChangeType.PUSH_ENTER && index < NUMBER_OF_CHILDREN - 1) {
-                        addChild(index + 1);
+                    if (changeType == ControllerChangeType.PUSH_ENTER && !hasShownAll) {
+                        if (index < NUMBER_OF_CHILDREN - 1) {
+                            addChild(index + 1);
+                        } else {
+                            hasShownAll = true;
+                        }
                     } else if (changeType == ControllerChangeType.POP_EXIT) {
                         if (index > 0) {
                             removeChild(index - 1);
@@ -66,16 +73,27 @@ public class ParentController extends BaseController {
     }
 
     private void removeChild(int index) {
-        removeChildRouter(getChildRouters().get(index));
+        List<Router> childRouters = getChildRouters();
+        if (index < childRouters.size()) {
+            removeChildRouter(childRouters.get(index));
+        }
     }
 
     @Override
     public boolean handleBack() {
-        if (!finishing) {
+        int childControllers = 0;
+        for (Router childRouter : getChildRouters()) {
+            if (childRouter.hasRootController()) {
+                childControllers++;
+            }
+        }
+
+        if (childControllers != NUMBER_OF_CHILDREN || finishing) {
+            return true;
+        } else {
             finishing = true;
             return super.handleBack();
         }
-        return true;
     }
 
     @Override

demo/src/main/java/com/bluelinelabs/conductor/demo/controllers/TransitionDemoController.java

@@ -140,11 +140,10 @@ public class TransitionDemoController extends BaseController {
 
     public static RouterTransaction getRouterTransaction(int index, Controller fromController) {
         TransitionDemoController toController = new TransitionDemoController(index);
-        ControllerChangeHandler changeHandler = toController.getChangeHandler(fromController);
 
         return RouterTransaction.with(toController)
-                .pushChangeHandler(changeHandler)
-                .popChangeHandler(changeHandler);
+                .pushChangeHandler(toController.getChangeHandler(fromController))
+                .popChangeHandler(toController.getChangeHandler(fromController));
     }
 
 }

demo/src/main/java/com/bluelinelabs/conductor/demo/controllers/base/ButterKnifeController.java

@@ -37,6 +37,7 @@ public abstract class ButterKnifeController extends RxController {
     protected void onDestroyView(View view) {
         super.onDestroyView(view);
         unbinder.unbind();
+        unbinder = null;
     }
 
 }

demo/src/main/java/com/bluelinelabs/conductor/demo/controllers/base/RefWatchingController.java

@@ -1,7 +1,10 @@
 package com.bluelinelabs.conductor.demo.controllers.base;
 
 import android.os.Bundle;
+import android.support.annotation.NonNull;
 
+import com.bluelinelabs.conductor.ControllerChangeHandler;
+import com.bluelinelabs.conductor.ControllerChangeType;
 import com.bluelinelabs.conductor.demo.DemoApplication;
 
 public abstract class RefWatchingController extends ButterKnifeController {
@@ -11,10 +14,24 @@ public abstract class RefWatchingController extends ButterKnifeController {
         super(args);
     }
 
+    private boolean hasExited;
+
     @Override
     public void onDestroy() {
         super.onDestroy();
-        DemoApplication.refWatcher.watch(this);
+
+        if (hasExited) {
+            DemoApplication.refWatcher.watch(this);
+        }
     }
 
+    @Override
+    protected void onChangeEnded(@NonNull ControllerChangeHandler changeHandler, @NonNull ControllerChangeType changeType) {
+        super.onChangeEnded(changeHandler, changeType);
+
+        hasExited = !changeType.isEnter;
+        if (isDestroyed()) {
+            DemoApplication.refWatcher.watch(this);
+        }
+    }
 }

dependencies.gradle

@@ -14,12 +14,13 @@ ext {
 
     picasso = 'com.squareup.picasso:picasso:2.5.2'
 
-    leakCanary = 'com.squareup.leakcanary:leakcanary-android:1.4-beta2'
-    leakCanaryNoOp = 'com.squareup.leakcanary:leakcanary-android-no-op:1.4-beta2'
+    leakCanary = 'com.squareup.leakcanary:leakcanary-android:1.4'
+    leakCanaryNoOp = 'com.squareup.leakcanary:leakcanary-android-no-op:1.4'
 
-    rxJava = 'io.reactivex:rxjava:1.1.0'
-    rxAndroid = 'io.reactivex:rxandroid:1.1.0'
-    rxLifecycle = 'com.trello:rxlifecycle:0.6.0'
+    rxJava = 'io.reactivex:rxjava:1.2.0'
+    rxAndroid = 'io.reactivex:rxandroid:1.2.1'
+    rxLifecycle = 'com.trello:rxlifecycle:0.8.0'
+    rxLifecycleAndroid = 'com.trello:rxlifecycle-android:0.8.0'
 
     junit = 'junit:junit:4.11'
     roboelectric = 'org.robolectric:robolectric:3.0'

gradle.properties

@@ -1,4 +1,4 @@
-VERSION_NAME=2.0.1-SNAPSHOT
+VERSION_NAME=2.0.4-SNAPSHOT
 VERSION_CODE=2
 GROUP=com.bluelinelabs
 

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Tue Jan 19 22:43:12 CST 2016
+#Mon Sep 05 10:45:48 CDT 2016
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.10-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-2.14.1-all.zip