Version bump

- Added a RouterPagerAdapter, which allows the use of Routers as pages

README.md

@@ -20,22 +20,22 @@ Conductor is architecture-agnostic and does not try to force any design decision
 ## Installation
 
 ```gradle
-compile 'com.bluelinelabs:conductor:2.0.4'
+compile 'com.bluelinelabs:conductor:2.0.5'
 
 // If you want the components that go along with
 // Android's support libraries (currently just a PagerAdapter):
-compile 'com.bluelinelabs:conductor-support:2.0.4'
+compile 'com.bluelinelabs:conductor-support:2.0.5'
 
 // If you want RxJava/RxAndroid lifecycle support:
-compile 'com.bluelinelabs:conductor-rxlifecycle:2.0.4'
+compile 'com.bluelinelabs:conductor-rxlifecycle:2.0.5'
 ```
 
 SNAPSHOT:
 
 ```gradle
-compile 'com.bluelinelabs:conductor:2.0.5-SNAPSHOT'
-compile 'com.bluelinelabs:conductor-support:2.0.5-SNAPSHOT'
-compile 'com.bluelinelabs:conductor-rxlifecycle:2.0.5-SNAPSHOT'
+compile 'com.bluelinelabs:conductor:2.0.6-SNAPSHOT'
+compile 'com.bluelinelabs:conductor-support:2.0.6-SNAPSHOT'
+compile 'com.bluelinelabs:conductor-rxlifecycle:2.0.6-SNAPSHOT'
 ```
 
 You also have to add the url to the snapshot repository:

build.gradle

@@ -3,7 +3,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.2.2'
+        classpath 'com.android.tools.build:gradle:2.2.3'
     }
 }
 

conductor-rxlifecycle2/build.gradle

@@ -0,0 +1,35 @@
+apply from: rootProject.file('dependencies.gradle')
+apply from: rootProject.file('gradle-mvn-push.gradle')
+
+apply plugin: 'com.android.library'
+
+android {
+    compileSdkVersion rootProject.ext.compileSdkVersion
+    buildToolsVersion rootProject.ext.buildToolsVersion
+
+    lintOptions {
+        abortOnError false
+    }
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_7
+        targetCompatibility JavaVersion.VERSION_1_7
+    }
+
+    defaultConfig {
+        minSdkVersion rootProject.ext.minSdkVersion
+        targetSdkVersion rootProject.ext.targetSdkVersion
+        versionCode Integer.parseInt(project.VERSION_CODE)
+        versionName project.VERSION_NAME
+    }
+}
+
+dependencies {
+    compile rootProject.ext.rxJava2
+    compile rootProject.ext.rxLifecycle2
+    compile rootProject.ext.rxLifecycleAndroid2
+
+    compile project(':conductor')
+}
+
+ext.artifactId = 'conductor-rxlifecycle2'

conductor-rxlifecycle2/gradle.properties

@@ -0,0 +1,3 @@
+POM_NAME=Conductor RxLifecycle2 Extensions
+POM_ARTIFACT_ID=conductor-rxlifecycle2
+POM_PACKAGING=aar

conductor-rxlifecycle2/src/main/AndroidManifest.xml

@@ -0,0 +1,4 @@
+<manifest package="com.bluelinelabs.conductor.rxlifecycle2">
+    <application />
+</manifest>
+

conductor-rxlifecycle2/src/main/java/com/bluelinelabs/conductor/rxlifecycle2/ControllerEvent.java

@@ -0,0 +1,12 @@
+package com.bluelinelabs.conductor.rxlifecycle2;
+
+public enum ControllerEvent {
+
+    CREATE,
+    CREATE_VIEW,
+    ATTACH,
+    DETACH,
+    DESTROY_VIEW,
+    DESTROY
+
+}

conductor-rxlifecycle2/src/main/java/com/bluelinelabs/conductor/rxlifecycle2/ControllerLifecycleSubjectHelper.java

@@ -0,0 +1,44 @@
+package com.bluelinelabs.conductor.rxlifecycle2;
+
+import android.support.annotation.NonNull;
+import android.view.View;
+import com.bluelinelabs.conductor.Controller;
+import io.reactivex.subjects.BehaviorSubject;
+
+public class ControllerLifecycleSubjectHelper {
+    private ControllerLifecycleSubjectHelper() {
+    }
+
+    public static BehaviorSubject<ControllerEvent> create(Controller controller){
+        final BehaviorSubject<ControllerEvent> subject = BehaviorSubject.createDefault(ControllerEvent.CREATE);
+
+        controller.addLifecycleListener(new Controller.LifecycleListener() {
+            @Override
+            public void preCreateView(@NonNull Controller controller) {
+                subject.onNext(ControllerEvent.CREATE_VIEW);
+            }
+
+            @Override
+            public void preAttach(@NonNull Controller controller, @NonNull View view) {
+                subject.onNext(ControllerEvent.ATTACH);
+            }
+
+            @Override
+            public void preDetach(@NonNull Controller controller, @NonNull View view) {
+                subject.onNext(ControllerEvent.DETACH);
+            }
+
+            @Override
+            public void preDestroyView(@NonNull Controller controller, @NonNull View view) {
+                subject.onNext(ControllerEvent.DESTROY_VIEW);
+            }
+
+            @Override
+            public void preDestroy(@NonNull Controller controller) {
+                subject.onNext(ControllerEvent.DESTROY);
+            }
+        });
+
+        return subject;
+    }
+}

conductor-rxlifecycle2/src/main/java/com/bluelinelabs/conductor/rxlifecycle2/RxController.java

@@ -0,0 +1,49 @@
+package com.bluelinelabs.conductor.rxlifecycle2;
+
+import android.os.Bundle;
+import android.support.annotation.CheckResult;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import com.bluelinelabs.conductor.Controller;
+import com.trello.rxlifecycle2.LifecycleProvider;
+import com.trello.rxlifecycle2.LifecycleTransformer;
+import com.trello.rxlifecycle2.RxLifecycle;
+import io.reactivex.Observable;
+import io.reactivex.subjects.BehaviorSubject;
+
+/**
+ * A base {@link Controller} that can be used to expose lifecycle events using RxJava
+ */
+public abstract class RxController extends Controller implements LifecycleProvider<ControllerEvent> {
+    private final BehaviorSubject<ControllerEvent> lifecycleSubject;
+
+    public RxController(){
+        this(null);
+    }
+
+    public RxController(@Nullable Bundle args) {
+        super(args);
+        lifecycleSubject = ControllerLifecycleSubjectHelper.create(this);
+    }
+
+    @Override
+    @NonNull
+    @CheckResult
+    public final Observable<ControllerEvent> lifecycle() {
+        return lifecycleSubject.hide();
+    }
+
+    @Override
+    @NonNull
+    @CheckResult
+    public final <T> LifecycleTransformer<T> bindUntilEvent(@NonNull ControllerEvent event) {
+        return RxLifecycle.bindUntilEvent(lifecycleSubject, event);
+    }
+
+    @Override
+    @NonNull
+    @CheckResult
+    public final <T> LifecycleTransformer<T> bindToLifecycle() {
+        return RxControllerLifecycle.bindController(lifecycleSubject);
+    }
+}

conductor-rxlifecycle2/src/main/java/com/bluelinelabs/conductor/rxlifecycle2/RxControllerLifecycle.java

@@ -0,0 +1,41 @@
+package com.bluelinelabs.conductor.rxlifecycle2;
+
+import android.support.annotation.NonNull;
+import com.trello.rxlifecycle2.LifecycleTransformer;
+import com.trello.rxlifecycle2.OutsideLifecycleException;
+import com.trello.rxlifecycle2.RxLifecycle;
+import io.reactivex.Observable;
+import io.reactivex.functions.Function;
+
+public class RxControllerLifecycle {
+
+    /**
+     * Binds the given source to a Controller lifecycle. This is the Controller version of
+     * {@link com.trello.rxlifecycle2.android.RxLifecycleAndroid#bindFragment(Observable)}.
+     *
+     * @param lifecycle the lifecycle sequence of a Controller
+     * @return a reusable {@link io.reactivex.ObservableTransformer} that unsubscribes the source during the Controller lifecycle
+     */
+    public static <T> LifecycleTransformer<T> bindController(@NonNull final Observable<ControllerEvent> lifecycle) {
+        return RxLifecycle.bind(lifecycle, CONTROLLER_LIFECYCLE);
+    }
+
+    private static final Function<ControllerEvent, ControllerEvent> CONTROLLER_LIFECYCLE =
+        new Function<ControllerEvent, ControllerEvent>() {
+            @Override
+            public ControllerEvent apply(ControllerEvent lastEvent) {
+                switch (lastEvent) {
+                    case CREATE:
+                        return ControllerEvent.DESTROY;
+                    case ATTACH:
+                        return ControllerEvent.DETACH;
+                    case CREATE_VIEW:
+                        return ControllerEvent.DESTROY_VIEW;
+                    case DETACH:
+                        return ControllerEvent.DESTROY;
+                    default:
+                        throw new OutsideLifecycleException("Cannot bind to Controller lifecycle when outside of it.");
+                }
+            }
+        };
+}

conductor-rxlifecycle2/src/main/java/com/bluelinelabs/conductor/rxlifecycle2/RxRestoreViewOnCreateController.java

@@ -0,0 +1,45 @@
+package com.bluelinelabs.conductor.rxlifecycle2;
+
+import android.os.Bundle;
+import android.support.annotation.CheckResult;
+import android.support.annotation.NonNull;
+import com.bluelinelabs.conductor.RestoreViewOnCreateController;
+import com.trello.rxlifecycle2.LifecycleProvider;
+import com.trello.rxlifecycle2.LifecycleTransformer;
+import com.trello.rxlifecycle2.RxLifecycle;
+import io.reactivex.Observable;
+import io.reactivex.subjects.BehaviorSubject;
+
+public abstract class RxRestoreViewOnCreateController extends RestoreViewOnCreateController implements LifecycleProvider<ControllerEvent> {
+    private final BehaviorSubject<ControllerEvent> lifecycleSubject;
+
+    public RxRestoreViewOnCreateController() {
+        this(null);
+    }
+
+    public RxRestoreViewOnCreateController(Bundle args) {
+        super(args);
+        lifecycleSubject = ControllerLifecycleSubjectHelper.create(this);
+    }
+
+    @Override
+    @NonNull
+    @CheckResult
+    public final Observable<ControllerEvent> lifecycle() {
+        return lifecycleSubject.hide();
+    }
+
+    @Override
+    @NonNull
+    @CheckResult
+    public final <T> LifecycleTransformer<T> bindUntilEvent(@NonNull ControllerEvent event) {
+        return RxLifecycle.bindUntilEvent(lifecycleSubject, event);
+    }
+
+    @Override
+    @NonNull
+    @CheckResult
+    public final <T> LifecycleTransformer<T> bindToLifecycle() {
+        return RxControllerLifecycle.bindController(lifecycleSubject);
+    }
+}

conductor-support/src/main/java/com/bluelinelabs/conductor/support/ControllerPagerAdapter.java

@@ -2,6 +2,7 @@ package com.bluelinelabs.conductor.support;
 
 import android.os.Bundle;
 import android.os.Parcelable;
+import android.support.annotation.Nullable;
 import android.support.v4.view.PagerAdapter;
 import android.util.SparseArray;
 import android.view.View;
@@ -18,10 +19,13 @@ public abstract class ControllerPagerAdapter extends PagerAdapter {
 
     private static final String KEY_SAVED_PAGES = "ControllerPagerAdapter.savedStates";
     private static final String KEY_SAVES_STATE = "ControllerPagerAdapter.savesState";
+    private static final String KEY_VISIBLE_PAGE_IDS_KEYS = "ControllerPagerAdapter.visiblePageIds.keys";
+    private static final String KEY_VISIBLE_PAGE_IDS_VALUES = "ControllerPagerAdapter.visiblePageIds.values";
 
     private final Controller host;
     private boolean savesState;
     private SparseArray<Bundle> savedPages = new SparseArray<>();
+    private SparseArray<String> visiblePageIds = new SparseArray<>();
 
     /**
      * Creates a new ControllerPagerAdapter using the passed host.
@@ -50,8 +54,9 @@ public abstract class ControllerPagerAdapter extends PagerAdapter {
         }
 
         if (!router.hasRootController()) {
-            router.setRoot(RouterTransaction.with(getItem(position))
-                    .tag(name));
+            Controller controller = getItem(position);
+            router.setRoot(RouterTransaction.with(controller).tag(name));
+            visiblePageIds.put(position, controller.getInstanceId());
         } else {
             router.rebindIfNeeded();
         }
@@ -69,6 +74,8 @@ public abstract class ControllerPagerAdapter extends PagerAdapter {
             savedPages.put(position, savedState);
         }
 
+        visiblePageIds.remove(position);
+
         host.removeChildRouter(router);
     }
 
@@ -82,6 +89,16 @@ public abstract class ControllerPagerAdapter extends PagerAdapter {
         Bundle bundle = new Bundle();
         bundle.putBoolean(KEY_SAVES_STATE, savesState);
         bundle.putSparseParcelableArray(KEY_SAVED_PAGES, savedPages);
+
+        int[] visiblePageIdsKeys = new int[visiblePageIds.size()];
+        String[] visiblePageIdsValues = new String[visiblePageIds.size()];
+        for (int i = 0; i < visiblePageIds.size(); i++) {
+            visiblePageIdsKeys[i] = visiblePageIds.keyAt(i);
+            visiblePageIdsValues[i] = visiblePageIds.valueAt(i);
+        }
+        bundle.putIntArray(KEY_VISIBLE_PAGE_IDS_KEYS, visiblePageIdsKeys);
+        bundle.putStringArray(KEY_VISIBLE_PAGE_IDS_VALUES, visiblePageIdsValues);
+
         return bundle;
     }
 
@@ -91,6 +108,26 @@ public abstract class ControllerPagerAdapter extends PagerAdapter {
         if (state != null) {
             savesState = bundle.getBoolean(KEY_SAVES_STATE, false);
             savedPages = bundle.getSparseParcelableArray(KEY_SAVED_PAGES);
+
+            int[] visiblePageIdsKeys = bundle.getIntArray(KEY_VISIBLE_PAGE_IDS_KEYS);
+            String[] visiblePageIdsValues = bundle.getStringArray(KEY_VISIBLE_PAGE_IDS_VALUES);
+            visiblePageIds = new SparseArray<>(visiblePageIdsKeys.length);
+            for (int i = 0; i < visiblePageIdsKeys.length; i++) {
+                visiblePageIds.put(visiblePageIdsKeys[i], visiblePageIdsValues[i]);
+            }
+        }
+    }
+
+    /**
+     * Returns the already instantiated Controller in the specified position, if available.
+     */
+    @Nullable
+    public Controller getController(int position) {
+        String instanceId = visiblePageIds.get(position);
+        if (instanceId != null) {
+            return host.getRouter().getControllerWithInstanceId(instanceId);
+        } else {
+            return null;
         }
     }
 

conductor-support/src/main/java/com/bluelinelabs/conductor/support/RouterPagerAdapter.java

@@ -0,0 +1,119 @@
+package com.bluelinelabs.conductor.support;
+
+import android.os.Bundle;
+import android.os.Parcelable;
+import android.support.annotation.Nullable;
+import android.support.v4.view.PagerAdapter;
+import android.util.SparseArray;
+import android.view.View;
+import android.view.ViewGroup;
+
+import com.bluelinelabs.conductor.Controller;
+import com.bluelinelabs.conductor.Router;
+import com.bluelinelabs.conductor.RouterTransaction;
+
+import java.util.List;
+
+/**
+ * An adapter for ViewPagers that uses Routers as pages
+ */
+public abstract class RouterPagerAdapter extends PagerAdapter {
+
+    private static final String KEY_SAVED_PAGES = "RouterPagerAdapter.savedStates";
+
+    private final Controller host;
+    private SparseArray<Bundle> savedPages = new SparseArray<>();
+    private SparseArray<Router> visibleRouters = new SparseArray<>();
+
+    /**
+     * Creates a new RouterPagerAdapter using the passed host.
+     */
+    public RouterPagerAdapter(Controller host) {
+        this.host = host;
+    }
+
+    /**
+     * Called when a router is instantiated. Here the router's root should be set if needed.
+     *
+     * @param router   The router used for the page
+     * @param position The page position to be instantiated.
+     */
+    public abstract void configureRouter(Router router, int position);
+
+    @Override
+    public Object instantiateItem(ViewGroup container, int position) {
+        final String name = makeRouterName(container.getId(), getItemId(position));
+
+        Router router = host.getChildRouter(container, name);
+        if (!router.hasRootController()) {
+            Bundle routerSavedState = savedPages.get(position);
+
+            if (routerSavedState != null) {
+                router.restoreInstanceState(routerSavedState);
+            }
+        }
+
+        router.rebindIfNeeded();
+        configureRouter(router, position);
+
+        visibleRouters.put(position, router);
+        return router;
+    }
+
+    @Override
+    public void destroyItem(ViewGroup container, int position, Object object) {
+        Router router = (Router)object;
+
+        Bundle savedState = new Bundle();
+        router.saveInstanceState(savedState);
+        savedPages.put(position, savedState);
+
+        host.removeChildRouter(router);
+
+        visibleRouters.remove(position);
+    }
+
+    @Override
+    public boolean isViewFromObject(View view, Object object) {
+        Router router = (Router)object;
+        final List<RouterTransaction> backstack = router.getBackstack();
+        for (RouterTransaction transaction : backstack) {
+            if (transaction.controller().getView() == view) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    @Override
+    public Parcelable saveState() {
+        Bundle bundle = new Bundle();
+        bundle.putSparseParcelableArray(KEY_SAVED_PAGES, savedPages);
+        return bundle;
+    }
+
+    @Override
+    public void restoreState(Parcelable state, ClassLoader loader) {
+        Bundle bundle = (Bundle)state;
+        if (state != null) {
+            savedPages = bundle.getSparseParcelableArray(KEY_SAVED_PAGES);
+        }
+    }
+
+    /**
+     * Returns the already instantiated Router in the specified position, if available.
+     */
+    @Nullable
+    public Router getRouter(int position) {
+        return visibleRouters.get(position);
+    }
+
+    public long getItemId(int position) {
+        return position;
+    }
+
+    private static String makeRouterName(int viewId, long id) {
+        return viewId + ":" + id;
+    }
+
+}

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

@@ -15,37 +15,37 @@ class Backstack implements Iterable<RouterTransaction> {
 
     private static final String KEY_ENTRIES = "Backstack.entries";
 
-    private final Deque<RouterTransaction> backStack = new ArrayDeque<>();
+    private final Deque<RouterTransaction> backstack = new ArrayDeque<>();
 
     @SuppressWarnings("BooleanMethodIsAlwaysInverted")
     public boolean isEmpty() {
-        return backStack.isEmpty();
+        return backstack.isEmpty();
     }
 
     public int size() {
-        return backStack.size();
+        return backstack.size();
     }
 
     @Nullable
     public RouterTransaction root() {
-        return backStack.size() > 0 ? backStack.getLast() : null;
+        return backstack.size() > 0 ? backstack.getLast() : null;
     }
 
     @Override @NonNull
     public Iterator<RouterTransaction> iterator() {
-        return backStack.iterator();
+        return backstack.iterator();
     }
 
     @NonNull
     public Iterator<RouterTransaction> reverseIterator() {
-        return backStack.descendingIterator();
+        return backstack.descendingIterator();
     }
 
     @NonNull
     public List<RouterTransaction> popTo(@NonNull RouterTransaction transaction) {
         List<RouterTransaction> popped = new ArrayList<>();
-        if (backStack.contains(transaction)) {
-            while (backStack.peek() != transaction) {
+        if (backstack.contains(transaction)) {
+            while (backstack.peek() != transaction) {
                 RouterTransaction poppedTransaction = pop();
                 popped.add(poppedTransaction);
             }
@@ -57,22 +57,22 @@ class Backstack implements Iterable<RouterTransaction> {
 
     @NonNull
     public RouterTransaction pop() {
-        RouterTransaction popped = backStack.pop();
+        RouterTransaction popped = backstack.pop();
         popped.controller.destroy();
         return popped;
     }
 
     @Nullable
     public RouterTransaction peek() {
-        return backStack.peek();
+        return backstack.peek();
     }
 
     public void remove(@NonNull RouterTransaction transaction) {
-        backStack.removeFirstOccurrence(transaction);
+        backstack.removeFirstOccurrence(transaction);
     }
 
     public void push(@NonNull RouterTransaction transaction) {
-        backStack.push(transaction);
+        backstack.push(transaction);
     }
 
     @NonNull
@@ -85,7 +85,7 @@ class Backstack implements Iterable<RouterTransaction> {
     }
 
     public void setBackstack(@NonNull List<RouterTransaction> backstack) {
-        for (RouterTransaction existingTransaction : backStack) {
+        for (RouterTransaction existingTransaction : this.backstack) {
             boolean contains = false;
             for (RouterTransaction newTransaction : backstack) {
                 if (existingTransaction.controller == newTransaction.controller) {
@@ -99,15 +99,15 @@ class Backstack implements Iterable<RouterTransaction> {
             }
         }
 
-        backStack.clear();
+        this.backstack.clear();
         for (RouterTransaction transaction : backstack) {
-            backStack.push(transaction);
+            this.backstack.push(transaction);
         }
     }
 
     public void saveInstanceState(@NonNull Bundle outState) {
-        ArrayList<Bundle> entryBundles = new ArrayList<>(backStack.size());
-        for (RouterTransaction entry : backStack) {
+        ArrayList<Bundle> entryBundles = new ArrayList<>(backstack.size());
+        for (RouterTransaction entry : backstack) {
             entryBundles.add(entry.saveInstanceState());
         }
 
@@ -119,7 +119,7 @@ class Backstack implements Iterable<RouterTransaction> {
         if (entryBundles != null) {
             Collections.reverse(entryBundles);
             for (Bundle transactionBundle : entryBundles) {
-                backStack.push(new RouterTransaction(transactionBundle));
+                backstack.push(new RouterTransaction(transactionBundle));
             }
         }
     }

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

@@ -44,6 +44,7 @@ public abstract class Controller {
     private static final String KEY_CLASS_NAME = "Controller.className";
     private static final String KEY_VIEW_STATE = "Controller.viewState";
     private static final String KEY_CHILD_ROUTERS = "Controller.childRouters";
+    private static final String KEY_CHILD_BACKSTACK = "Controller.childBackstack";
     private static final String KEY_SAVED_STATE = "Controller.savedState";
     private static final String KEY_INSTANCE_ID = "Controller.instanceId";
     private static final String KEY_TARGET_INSTANCE_ID = "Controller.target.instanceId";
@@ -130,7 +131,7 @@ public abstract class Controller {
      * @param args Any arguments that need to be retained.
      */
     protected Controller(@Nullable Bundle args) {
-        this.args = args;
+        this.args = args != null ? args : new Bundle();
         instanceId = UUID.randomUUID().toString();
         ensureRequiredConstructor();
     }
@@ -158,7 +159,7 @@ public abstract class Controller {
     /**
      * Returns any arguments that were set in this Controller's constructor
      */
-    @Nullable
+    @NonNull
     public Bundle getArgs() {
         return args;
     }
@@ -171,7 +172,6 @@ public abstract class Controller {
      */
     @NonNull
     public final Router getChildRouter(@NonNull ViewGroup container) {
-        //noinspection deprecation
         return getChildRouter(container, null);
     }
 
@@ -186,6 +186,21 @@ public abstract class Controller {
      */
     @NonNull
     public final Router getChildRouter(@NonNull ViewGroup container, @Nullable String tag) {
+        //noinspection ConstantConditions
+        return getChildRouter(container, tag, true);
+    }
+
+    /**
+     * Retrieves the child {@link Router} for the given container/tag combination. Note that multiple
+     * routers should not exist in the same container unless a lot of care is taken to maintain order
+     * between them. Avoid using the same container unless you have a great reason to do so (ex: ViewPagers).
+     *
+     * @param container The ViewGroup that hosts the child Router
+     * @param tag The router's tag
+     * @param createIfNeeded If true, a router will be created if one does not yet exist. Else false will be returned in this case.
+     */
+    @Nullable
+    public final Router getChildRouter(@NonNull ViewGroup container, @Nullable String tag, boolean createIfNeeded) {
         @IdRes final int containerId = container.getId();
 
         ControllerHostedRouter childRouter = null;
@@ -197,10 +212,12 @@ public abstract class Controller {
         }
 
         if (childRouter == null) {
-            childRouter = new ControllerHostedRouter(container.getId(), tag);
-            monitorChildRouter(childRouter);
-            childRouter.setHost(this, container);
-            childRouters.add(childRouter);
+            if (createIfNeeded) {
+                childRouter = new ControllerHostedRouter(container.getId(), tag);
+                monitorChildRouter(childRouter);
+                childRouter.setHost(this, container);
+                childRouters.add(childRouter);
+            }
         } else if (!childRouter.hasHost()) {
             childRouter.setHost(this, container);
             monitorChildRouter(childRouter);
@@ -865,6 +882,9 @@ public abstract class Controller {
             }
 
             view = onCreateView(LayoutInflater.from(parent.getContext()), parent);
+            if (view == parent) {
+                throw new IllegalStateException("Controller's onCreateView method returned the parent ViewGroup. Perhaps you forgot to pass false for LayoutInflater.inflate's attachToRoot parameter?");
+            }
 
             listeners = new ArrayList<>(lifecycleListeners);
             for (LifecycleListener lifecycleListener : listeners) {
@@ -895,11 +915,27 @@ public abstract class Controller {
             };
 
             view.addOnAttachStateChangeListener(onAttachStateChangeListener);
+        } else if (retainViewMode == RetainViewMode.RETAIN_DETACH) {
+            restoreChildControllerHosts();
         }
 
         return view;
     }
 
+    private void restoreChildControllerHosts() {
+        for (ControllerHostedRouter childRouter : childRouters) {
+            if (!childRouter.hasHost()) {
+                View containerView = view.findViewById(childRouter.getHostId());
+
+                if (containerView != null && containerView instanceof ViewGroup) {
+                    childRouter.setHost(this, (ViewGroup)containerView);
+                    monitorChildRouter(childRouter);
+                    childRouter.rebindIfNeeded();
+                }
+            }
+        }
+    }
+
     private void performDestroy() {
         if (!destroyed) {
             List<LifecycleListener> listeners = new ArrayList<>(lifecycleListeners);
@@ -966,17 +1002,7 @@ public abstract class Controller {
             view.restoreHierarchyState(viewState.getSparseParcelableArray(KEY_VIEW_STATE_HIERARCHY));
             onRestoreViewState(view, viewState.getBundle(KEY_VIEW_STATE_BUNDLE));
 
-            for (ControllerHostedRouter childRouter : childRouters) {
-                if (!childRouter.hasHost()) {
-                    View containerView = view.findViewById(childRouter.getHostId());
-
-                    if (containerView != null && containerView instanceof ViewGroup) {
-                        childRouter.setHost(this, (ViewGroup)containerView);
-                        monitorChildRouter(childRouter);
-                        childRouter.rebindIfNeeded();
-                    }
-                }
-            }
+            restoreChildControllerHosts();
 
             List<LifecycleListener> listeners = new ArrayList<>(lifecycleListeners);
             for (LifecycleListener lifecycleListener : listeners) {
@@ -1015,6 +1041,12 @@ public abstract class Controller {
         }
         outState.putParcelableArrayList(KEY_CHILD_ROUTERS, childBundles);
 
+        ArrayList<String> childBackstack = new ArrayList<>();
+        for (Controller controller : this.childBackstack) {
+            childBackstack.add(controller.instanceId);
+        }
+        outState.putStringArrayList(KEY_CHILD_BACKSTACK, childBackstack);
+
         Bundle savedState = new Bundle();
         onSaveInstanceState(savedState);
 
@@ -1046,6 +1078,14 @@ public abstract class Controller {
             childRouters.add(childRouter);
         }
 
+        List<String> childBackstackIds = savedInstanceState.getStringArrayList(KEY_CHILD_BACKSTACK);
+        for (String controllerId : childBackstackIds) {
+            Controller childController = findController(controllerId);
+            if (childController != null) {
+                childBackstack.add(childController);
+            }
+        }
+
         this.savedInstanceState = savedInstanceState.getBundle(KEY_SAVED_STATE);
         performOnRestoreInstanceState();
     }

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

@@ -275,29 +275,9 @@ public abstract class Router {
      */
     @UiThread
     public void setRoot(@NonNull RouterTransaction transaction) {
-        ControllerChangeHandler newHandler = transaction.pushChangeHandler() != null ? transaction.pushChangeHandler() : new SimpleSwapChangeHandler();
-
-        List<RouterTransaction> visibleTransactions = getVisibleTransactions(backstack.iterator());
-        RouterTransaction rootTransaction = visibleTransactions.size() > 0 ? visibleTransactions.get(0) : null;
-
-        removeAllExceptVisibleAndUnowned();
-
-        trackDestroyingControllers(backstack.popAll());
-
-        pushToBackstack(transaction);
-
-        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);
+        List<RouterTransaction> transactions = new ArrayList<>();
+        transactions.add(transaction);
+        setBackstack(transactions, transaction.pushChangeHandler());
     }
 
     /**
@@ -364,6 +344,12 @@ public abstract class Router {
     public void setBackstack(@NonNull List<RouterTransaction> newBackstack, @Nullable ControllerChangeHandler changeHandler) {
         List<RouterTransaction> oldVisibleTransactions = getVisibleTransactions(backstack.iterator());
 
+        backstack.setBackstack(newBackstack);
+
+        for (RouterTransaction transaction : backstack) {
+            transaction.onAttachedToRouter();
+        }
+
         removeAllExceptVisibleAndUnowned();
 
         if (newBackstack.size() > 0) {
@@ -385,7 +371,7 @@ public abstract class Router {
                 ControllerChangeHandler handler = changeHandler != null ? changeHandler : new SimpleSwapChangeHandler();
 
                 Controller rootController = oldVisibleTransactions.size() > 0 ? oldVisibleTransactions.get(0).controller : null;
-                performControllerChange(newVisibleTransactions.get(0).controller, rootController, true, handler.copy());
+                performControllerChange(newVisibleTransactions.get(0).controller, rootController, true, handler);
 
                 for (int i = oldVisibleTransactions.size() - 1; i > 0; i--) {
                     RouterTransaction transaction = oldVisibleTransactions.get(i);
@@ -402,12 +388,6 @@ public abstract class Router {
             }
         }
 
-        for (RouterTransaction transaction : backstack) {
-            transaction.onAttachedToRouter();
-        }
-
-        backstack.setBackstack(newBackstack);
-
         if (onControllerPushedListener != null) {
             for (RouterTransaction transaction : newBackstack) {
                 onControllerPushedListener.onControllerPushed(transaction.controller);

demo/build.gradle

@@ -37,6 +37,10 @@ android {
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
         }
     }
+
+    packagingOptions {
+        exclude 'META-INF/rxjava.properties'
+    }
 }
 
 dependencies {
@@ -49,6 +53,7 @@ dependencies {
 
     compile project(':conductor-support')
     compile project(':conductor-rxlifecycle')
+    compile project(':conductor-rxlifecycle2')
 
     debugCompile rootProject.ext.leakCanary
     releaseCompile rootProject.ext.leakCanaryNoOp

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

@@ -46,6 +46,7 @@ public class HomeController extends BaseController {
         MASTER_DETAIL("Master Detail", R.color.grey_300),
         DRAG_DISMISS("Drag Dismiss", R.color.lime_300),
         RX_LIFECYCLE("Rx Lifecycle", R.color.teal_300),
+        RX_LIFECYCLE_2("Rx Lifecycle 2", R.color.brown_300),
         OVERLAY("Overlay Controller", R.color.purple_300);
 
         String title;
@@ -176,6 +177,11 @@ public class HomeController extends BaseController {
                         .pushChangeHandler(new FadeChangeHandler())
                         .popChangeHandler(new FadeChangeHandler()));
                 break;
+            case RX_LIFECYCLE_2:
+                getRouter().pushController(RouterTransaction.with(new RxLifecycle2Controller())
+                        .pushChangeHandler(new FadeChangeHandler())
+                        .popChangeHandler(new FadeChangeHandler()));
+                break;
             case MULTIPLE_CHILD_ROUTERS:
                 getRouter().pushController(RouterTransaction.with(new MultipleChildRouterController())
                         .pushChangeHandler(new FadeChangeHandler())

demo/src/main/java/com/bluelinelabs/conductor/demo/controllers/RxLifecycle2Controller.java

@@ -0,0 +1,163 @@
+package com.bluelinelabs.conductor.demo.controllers;
+
+import android.support.annotation.NonNull;
+import android.util.Log;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.TextView;
+
+import com.bluelinelabs.conductor.ControllerChangeHandler;
+import com.bluelinelabs.conductor.ControllerChangeType;
+import com.bluelinelabs.conductor.RouterTransaction;
+import com.bluelinelabs.conductor.changehandler.HorizontalChangeHandler;
+import com.bluelinelabs.conductor.demo.ActionBarProvider;
+import com.bluelinelabs.conductor.demo.DemoApplication;
+import com.bluelinelabs.conductor.demo.R;
+import com.bluelinelabs.conductor.rxlifecycle2.ControllerEvent;
+import com.bluelinelabs.conductor.rxlifecycle2.RxController;
+
+import java.util.concurrent.TimeUnit;
+
+import butterknife.BindView;
+import butterknife.ButterKnife;
+import butterknife.OnClick;
+import butterknife.Unbinder;
+import io.reactivex.Observable;
+import io.reactivex.functions.Action;
+import io.reactivex.functions.Consumer;
+
+// Shamelessly borrowed from the official RxLifecycle demo by Trello and adapted for Conductor Controllers
+// instead of Activities or Fragments.
+public class RxLifecycle2Controller extends RxController {
+
+    private static final String TAG = "RxLifecycleController";
+
+    @BindView(R.id.tv_title) TextView tvTitle;
+
+    private Unbinder unbinder;
+    private boolean hasExited;
+
+    public RxLifecycle2Controller() {
+        Observable.interval(1, TimeUnit.SECONDS)
+                .doOnDispose(new Action() {
+                    @Override
+                    public void run() {
+                        Log.i(TAG, "Disposing from constructor");
+                    }
+                })
+                .compose(this.<Long>bindUntilEvent(ControllerEvent.DESTROY))
+                .subscribe(new Consumer<Long>() {
+                    @Override
+                    public void accept(Long num) {
+                        Log.i(TAG, "Started in constructor, running until onDestroy(): " + num);
+                    }
+                });
+    }
+
+    @NonNull
+    @Override
+    protected View onCreateView(@NonNull LayoutInflater inflater, @NonNull ViewGroup container) {
+        Log.i(TAG, "onCreateView() called");
+
+        View view = inflater.inflate(R.layout.controller_rxlifecycle, container, false);
+        unbinder = ButterKnife.bind(this, view);
+
+        tvTitle.setText(getResources().getString(R.string.rxlifecycle_title, TAG));
+
+        Observable.interval(1, TimeUnit.SECONDS)
+                .doOnDispose(new Action() {
+                    @Override
+                    public void run() {
+                        Log.i(TAG, "Disposing from onCreateView)");
+                    }
+                })
+                .compose(this.<Long>bindUntilEvent(ControllerEvent.DESTROY_VIEW))
+                .subscribe(new Consumer<Long>() {
+                    @Override
+                    public void accept(Long num) {
+                        Log.i(TAG, "Started in onCreateView(), running until onDestroyView(): " + num);
+                    }
+                });
+
+        return view;
+    }
+
+    @Override
+    protected void onAttach(@NonNull View view) {
+        super.onAttach(view);
+
+        Log.i(TAG, "onAttach() called");
+
+        (((ActionBarProvider)getActivity()).getSupportActionBar()).setTitle("RxLifecycle2 Demo");
+
+        Observable.interval(1, TimeUnit.SECONDS)
+                .doOnDispose(new Action() {
+                    @Override
+                    public void run() {
+                        Log.i(TAG, "Disposing from onAttach()");
+                    }
+                })
+                .compose(this.<Long>bindUntilEvent(ControllerEvent.DETACH))
+                .subscribe(new Consumer<Long>() {
+                    @Override
+                    public void accept(Long num) {
+                        Log.i(TAG, "Started in onAttach(), running until onDetach(): " + num);
+                    }
+                });
+    }
+
+    @Override
+    protected void onDestroyView(@NonNull View view) {
+        super.onDestroyView(view);
+
+        Log.i(TAG, "onDestroyView() called");
+
+        unbinder.unbind();
+        unbinder = null;
+    }
+
+    @Override
+    protected void onDetach(@NonNull View view) {
+        super.onDetach(view);
+
+        Log.i(TAG, "onDetach() called");
+    }
+
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+
+        Log.i(TAG, "onDestroy() called");
+
+        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);
+        }
+    }
+
+    @OnClick(R.id.btn_next_release_view) void onNextWithReleaseClicked() {
+        setRetainViewMode(RetainViewMode.RELEASE_DETACH);
+
+        getRouter().pushController(RouterTransaction.with(new TextController("Logcat should now report that the observables from onAttach() and onViewBound() have been disposed of, while the constructor observable is still running."))
+                .pushChangeHandler(new HorizontalChangeHandler())
+                .popChangeHandler(new HorizontalChangeHandler()));
+    }
+
+    @OnClick(R.id.btn_next_retain_view) void onNextWithRetainClicked() {
+        setRetainViewMode(RetainViewMode.RETAIN_DETACH);
+
+        getRouter().pushController(RouterTransaction.with(new TextController("Logcat should now report that the observables from onAttach() has been disposed of, while the constructor and onViewBound() observables are still running."))
+                .pushChangeHandler(new HorizontalChangeHandler())
+                .popChangeHandler(new HorizontalChangeHandler()));
+    }
+}

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

@@ -7,30 +7,38 @@ import android.view.View;
 import android.view.ViewGroup;
 import android.widget.TextView;
 
+import com.bluelinelabs.conductor.ControllerChangeHandler;
+import com.bluelinelabs.conductor.ControllerChangeType;
 import com.bluelinelabs.conductor.RouterTransaction;
 import com.bluelinelabs.conductor.changehandler.HorizontalChangeHandler;
+import com.bluelinelabs.conductor.demo.ActionBarProvider;
+import com.bluelinelabs.conductor.demo.DemoApplication;
 import com.bluelinelabs.conductor.demo.R;
-import com.bluelinelabs.conductor.demo.controllers.base.BaseController;
 import com.bluelinelabs.conductor.rxlifecycle.ControllerEvent;
+import com.bluelinelabs.conductor.rxlifecycle.RxController;
 
 import java.util.concurrent.TimeUnit;
 
 import butterknife.BindView;
+import butterknife.ButterKnife;
 import butterknife.OnClick;
+import butterknife.Unbinder;
 import rx.Observable;
 import rx.functions.Action0;
 import rx.functions.Action1;
 
 // Shamelessly borrowed from the official RxLifecycle demo by Trello and adapted for Conductor Controllers
 // instead of Activities or Fragments.
-public class RxLifecycleController extends BaseController {
+public class RxLifecycleController extends RxController {
 
     private static final String TAG = "RxLifecycleController";
 
     @BindView(R.id.tv_title) TextView tvTitle;
 
-    public RxLifecycleController() {
+    private Unbinder unbinder;
+    private boolean hasExited;
 
+    public RxLifecycleController() {
         Observable.interval(1, TimeUnit.SECONDS)
                 .doOnUnsubscribe(new Action0() {
                     @Override
@@ -47,10 +55,14 @@ public class RxLifecycleController extends BaseController {
                 });
     }
 
+    @NonNull
     @Override
-    public void onViewBound(@NonNull View view) {
+    protected View onCreateView(@NonNull LayoutInflater inflater, @NonNull ViewGroup container) {
         Log.i(TAG, "onCreateView() called");
 
+        View view = inflater.inflate(R.layout.controller_rxlifecycle, container, false);
+        unbinder = ButterKnife.bind(this, view);
+
         tvTitle.setText(getResources().getString(R.string.rxlifecycle_title, TAG));
 
         Observable.interval(1, TimeUnit.SECONDS)
@@ -67,6 +79,8 @@ public class RxLifecycleController extends BaseController {
                         Log.i(TAG, "Started in onCreateView(), running until onDestroyView(): " + num);
                     }
                 });
+
+        return view;
     }
 
     @Override
@@ -75,6 +89,8 @@ public class RxLifecycleController extends BaseController {
 
         Log.i(TAG, "onAttach() called");
 
+        (((ActionBarProvider)getActivity()).getSupportActionBar()).setTitle("RxLifecycle Demo");
+
         Observable.interval(1, TimeUnit.SECONDS)
                 .doOnUnsubscribe(new Action0() {
                     @Override
@@ -96,6 +112,9 @@ public class RxLifecycleController extends BaseController {
         super.onDestroyView(view);
 
         Log.i(TAG, "onDestroyView() called");
+
+        unbinder.unbind();
+        unbinder = null;
     }
 
     @Override
@@ -110,17 +129,20 @@ public class RxLifecycleController extends BaseController {
         super.onDestroy();
 
         Log.i(TAG, "onDestroy() called");
+
+        if (hasExited) {
+            DemoApplication.refWatcher.watch(this);
+        }
     }
 
     @Override
-    protected String getTitle() {
-        return "RxLifecycle Demo";
-    }
+    protected void onChangeEnded(@NonNull ControllerChangeHandler changeHandler, @NonNull ControllerChangeType changeType) {
+        super.onChangeEnded(changeHandler, changeType);
 
-    @NonNull
-    @Override
-    protected View inflateView(@NonNull LayoutInflater inflater, @NonNull ViewGroup container) {
-        return inflater.inflate(R.layout.controller_rxlifecycle, container, false);
+        hasExited = !changeType.isEnter;
+        if (isDestroyed()) {
+            DemoApplication.refWatcher.watch(this);
+        }
     }
 
     @OnClick(R.id.btn_next_release_view) void onNextWithReleaseClicked() {

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

@@ -6,12 +6,12 @@ import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 
-import com.bluelinelabs.conductor.rxlifecycle.RxController;
+import com.bluelinelabs.conductor.Controller;
 
 import butterknife.ButterKnife;
 import butterknife.Unbinder;
 
-public abstract class ButterKnifeController extends RxController {
+public abstract class ButterKnifeController extends Controller {
 
     private Unbinder unbinder;
 

dependencies.gradle

@@ -18,10 +18,16 @@ ext {
     leakCanaryNoOp = 'com.squareup.leakcanary:leakcanary-android-no-op:1.4'
 
     rxJava = 'io.reactivex:rxjava:1.2.0'
+    rxJava2 = "io.reactivex.rxjava2:rxjava:2.0.1"
+
     rxAndroid = 'io.reactivex:rxandroid:1.2.1'
+
     rxLifecycle = 'com.trello:rxlifecycle:0.8.0'
     rxLifecycleAndroid = 'com.trello:rxlifecycle-android:0.8.0'
 
+    rxLifecycle2 = "com.trello.rxlifecycle2:rxlifecycle:2.0"
+    rxLifecycleAndroid2 = "com.trello.rxlifecycle2:rxlifecycle-android:2.0"
+
     junit = 'junit:junit:4.11'
     roboelectric = 'org.robolectric:robolectric:3.0'
 

gradle.properties

@@ -1,4 +1,4 @@
-VERSION_NAME=2.0.5-SNAPSHOT
+VERSION_NAME=2.0.6-SNAPSHOT
 VERSION_CODE=2
 GROUP=com.bluelinelabs
 

settings.gradle

@@ -1,5 +1,6 @@
 include ':conductor'
-include':conductor-support'
-include':conductor-rxlifecycle'
-include':conductor-lint'
-include':demo'
+include ':conductor-support'
+include ':conductor-rxlifecycle'
+include ':conductor-rxlifecycle2'
+include ':conductor-lint'
+include ':demo'