WIP: add default destination.

library/src/main/kotlin/com/github/terrakok/cicerone/graph/GraphRouter.kt

@@ -0,0 +1,134 @@
+package com.github.terrakok.cicerone.graph
+
+import com.github.terrakok.cicerone.*
+
+
+class GraphRouter(
+    private val root: Root
+) : BaseRouter() {
+    private val vertexes: Map<String, Vertex>
+    private val currentPath: MutableList<String>
+    val currentVertex get() = vertexes.getValue(currentPath.last())
+
+    init {
+        val allVertexes = mutableMapOf<String, Vertex>()
+        val links = mutableSetOf<VertexLink>()
+        val jumps = mutableListOf<List<String>>()
+        validateGraph(root.vertex, allVertexes, links, jumps)
+
+        val linkAndJumpIds = links.map { it.id } + jumps.flatten()
+        linkAndJumpIds.forEach { id ->
+            require(allVertexes.containsKey(id)) { "Not found vertex for id=$id" }
+        }
+
+        vertexes = allVertexes
+        currentPath = mutableListOf(root.vertex.id)
+
+        jumps.forEach {
+            require(validateJump(it)) { "Invalid jump path=$it" }
+        }
+
+        if (root.defaultDestination != null) {
+            require(root.vertex.edges.any { it.id == root.defaultDestination })  { "Not found default destination" }
+            navigateTo(root.defaultDestination)
+        }
+    }
+
+    private fun validateGraph(
+        vertex: Vertex,
+        allVertexes: MutableMap<String, Vertex>,
+        links: MutableSet<VertexLink>,
+        jumps: MutableList<List<String>>
+    ) {
+        if (allVertexes.containsKey(vertex.id)) error("Graph contains duplicate id ${vertex.id}")
+        allVertexes[vertex.id] = vertex
+
+        links.addAll(vertex.edges.filterIsInstance<VertexLink>())
+        jumps.addAll(vertex.jumps.map { listOf(it.backTo ?: vertex.id, *it.chain.toTypedArray()) })
+        vertex.edges.forEach {
+            if (it !is VertexLink) validateGraph(it, allVertexes, links, jumps)
+        }
+    }
+
+    private fun validateJump(path: List<String>): Boolean {
+        if (path.isEmpty()) return false
+        if (path.size == 1) return true
+
+        val v = vertexes.getValue(path[0])
+        v.edges.firstOrNull { it.id == path[1] } ?: return false
+        return validateJump(path.subList(1, path.size))
+    }
+
+    fun navigateTo(
+        vertexId: String,
+        screenFactory: (vertexId: String) -> Screen? = { null }
+    ) {
+        val destination = currentVertex.edges.first { it.id == vertexId }
+        val screen = createScreen(destination.id, screenFactory)
+        val command =
+            if (currentVertex.id == Root.ID) Replace(screen)
+            else Forward(screen, destination.destroyPreviousView)
+        currentPath.add(destination.id)
+        executeCommands(command)
+    }
+
+    fun jumpTo(
+        jumpId: String,
+        screenFactory: (vertexId: String) -> Screen? = { null }
+    ) {
+        val jump = currentVertex.jumps.first { it.id == jumpId }
+
+        if (jump.backTo == Root.ID && jump.chain.isEmpty()) {
+            finish()
+            return
+        }
+
+        val commands = mutableListOf<Command>().apply {
+            if (jump.backTo != null) {
+                val id = jump.backTo
+                val index = currentPath.indexOfFirst { it == id }
+                if (index == -1) error("Current path doesn't contain vertex $id")
+                currentPath.subList(index + 1, currentPath.size).clear()
+                if (jump.backTo == Root.ID) add(BackTo(null))
+                else add(BackTo(Key(id)))
+            }
+            jump.chain.forEachIndexed { index, vertexId ->
+                val screen = createScreen(vertexId, screenFactory)
+                currentPath.add(vertexId)
+                if (index == 0 && jump.backTo == Root.ID) {
+                    add(Replace(screen))
+                } else {
+                    add(Forward(screen, vertexes.getValue(vertexId).destroyPreviousView))
+                }
+            }
+        }
+
+        executeCommands(*commands.toTypedArray())
+    }
+
+    fun exit() {
+        currentPath.removeLast()
+        executeCommands(Back())
+    }
+
+    private fun finish() {
+        currentPath.clear()
+        currentPath.add(Root.ID)
+        executeCommands(BackTo(null), Back())
+    }
+
+    private fun createScreen(
+        vertexId: String,
+        screenFactory: (vertexId: String) -> Screen?
+    ): Screen {
+        val screen = screenFactory(vertexId)
+            ?: vertexes.getValue(vertexId).screenFactory(vertexId)
+            ?: error("Unknown screen for vertex $vertexId")
+        require(screen.screenKey == vertexId) { "Screen key must be equal vertex id!" }
+        return screen
+    }
+
+    private class Key(
+        override val screenKey: String
+    ) : Screen
+}

library/src/main/kotlin/com/github/terrakok/cicerone/graph/Vertex.kt

@@ -0,0 +1,134 @@
+package com.github.terrakok.cicerone.graph
+
+import com.github.terrakok.cicerone.*
+
+open class Vertex internal constructor(
+    val id: String,
+    val edges: Set<Vertex>,
+    val jumps: Set<Jump>,
+    val destroyPreviousView: Boolean = true,
+    val screenFactory: (id: String) -> Screen? = { null }
+) {
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (javaClass != other?.javaClass) return false
+
+        other as Vertex
+
+        if (id != other.id) return false
+
+        return true
+    }
+
+    override fun hashCode(): Int {
+        return id.hashCode()
+    }
+}
+
+internal class VertexLink(
+    id: String,
+    destroyPreviousView: Boolean = true
+): Vertex(id, emptySet(), emptySet(), destroyPreviousView)
+
+class Jump(
+    val id: String,
+    val backTo: String?,
+    val chain: List<String>
+) {
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (javaClass != other?.javaClass) return false
+
+        other as Jump
+
+        if (id != other.id) return false
+
+        return true
+    }
+
+    override fun hashCode(): Int {
+        return id.hashCode()
+    }
+}
+
+//Graph DSL
+
+class GraphInfo(
+    var edges: MutableSet<Vertex>.() -> Unit = {},
+    var jumps: MutableSet<Jump>.() -> Unit = {}
+)
+
+class Root(
+    val vertex: Vertex,
+    val defaultDestination: String?
+) {
+    companion object {
+        const val ID = "graph-root"
+    }
+}
+
+fun graph(
+    defaultDestination: String? = null,
+    setup: GraphInfo.() -> Unit
+): Root {
+    val info = GraphInfo().apply(setup)
+    val v = Vertex(
+        Root.ID,
+        mutableSetOf<Vertex>().apply(info.edges),
+        mutableSetOf<Jump>().apply(info.jumps)
+    )
+    return Root(v, defaultDestination)
+}
+
+class VertexInfo(
+    var edges: MutableSet<Vertex>.() -> Unit = {},
+    var jumps: MutableSet<Jump>.() -> Unit = {},
+    var screen: (id: String) -> Screen? = { null }
+)
+
+fun MutableSet<Vertex>.dest(
+    id: String,
+    destroyPreviousView: Boolean = true,
+    setup: VertexInfo.() -> Unit = {}
+) {
+    val info = VertexInfo().apply(setup)
+    add(Vertex(
+        id,
+        mutableSetOf<Vertex>().apply(info.edges),
+        mutableSetOf<Jump>().apply(info.jumps),
+        destroyPreviousView,
+        info.screen
+    ))
+}
+
+fun MutableSet<Vertex>.edge(
+    id: String,
+    destroyPreviousView: Boolean = true
+) {
+    add(VertexLink(id, destroyPreviousView))
+}
+
+class JumpInfo(
+    var backTo: String? = null,
+    internal var chain: List<String> = emptyList()
+) {
+    fun chain(vararg id: String) {
+        chain = id.toList()
+    }
+}
+
+fun MutableSet<Jump>.jump(
+    id: String,
+    setup: JumpInfo.() -> Unit
+) {
+    val info = JumpInfo().apply(setup)
+    add(Jump(
+        id,
+        info.backTo,
+        info.chain
+    ))
+}
+
+fun MutableSet<Jump>.finish(id: String) {
+    add(Jump(id, Root.ID, emptyList()))
+}

sample/src/main/AndroidManifest.xml

@@ -21,5 +21,6 @@
         <activity android:name=".ui.main.MainActivity"/>
         <activity android:name=".ui.bottom.BottomNavigationActivity"/>
         <activity android:name=".ui.animations.ProfileActivity"/>
+        <activity android:name=".ui.graph.GraphActivity"/>
     </application>
 </manifest>

sample/src/main/java/com/github/terrakok/cicerone/sample/NavGraph.kt

@@ -0,0 +1,75 @@
+package com.github.terrakok.cicerone.sample
+
+import com.github.terrakok.cicerone.androidx.FragmentScreen
+import com.github.terrakok.cicerone.graph.*
+import com.github.terrakok.cicerone.sample.ui.graph.ForkFragment
+import com.github.terrakok.cicerone.sample.ui.graph.RoadFragment
+
+private val RoadScreen = { id: String -> FragmentScreen(id) { RoadFragment.getNewInstance(id) } }
+private val ForkScreen = { id: String -> FragmentScreen(id) { ForkFragment.getNewInstance(id) } }
+
+fun Graph() = graph("8") {
+    edges = {
+        dest("1") {
+            screen = RoadScreen
+            edges = {
+                dest("2") {
+                    screen = ForkScreen
+                    edges = {
+                        dest("3") {
+                            screen = RoadScreen
+                            edges = {
+                                dest("4") {
+                                    screen = RoadScreen
+                                    edges = {
+                                        edge("5")
+                                    }
+                                }
+                            }
+                        }
+                        dest("5") {
+                            screen = ForkScreen
+                            edges = {
+                                dest("6") {
+                                    screen = RoadScreen
+                                }
+                                dest("7") {
+                                    screen = RoadScreen
+                                    jumps = {
+                                        finish("1")
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        dest("8") {
+            screen = ForkScreen
+            edges = {
+                dest("9") {
+                    screen = RoadScreen
+                    edges = {
+                        edge("1")
+                    }
+                    jumps = {
+                        jump("1") {
+                            backTo = Root.ID
+                            chain("1", "2", "3", "4", "5", "7")
+                        }
+                    }
+                }
+                dest("10") {
+                    screen = ForkScreen
+                    edges = {
+                        dest("11") {
+                            screen = RoadScreen
+                        }
+                        edge("10")
+                    }
+                }
+            }
+        }
+    }
+}

sample/src/main/java/com/github/terrakok/cicerone/sample/Screens.kt

@@ -10,6 +10,7 @@ import com.github.terrakok.cicerone.sample.ui.animations.profile.ProfileFragment
 import com.github.terrakok.cicerone.sample.ui.bottom.BottomNavigationActivity
 import com.github.terrakok.cicerone.sample.ui.bottom.ForwardFragment
 import com.github.terrakok.cicerone.sample.ui.bottom.TabContainerFragment
+import com.github.terrakok.cicerone.sample.ui.graph.GraphActivity
 import com.github.terrakok.cicerone.sample.ui.main.MainActivity
 import com.github.terrakok.cicerone.sample.ui.main.SampleFragment
 import com.github.terrakok.cicerone.sample.ui.start.StartActivity
@@ -59,4 +60,8 @@ object Screens {
     fun SelectPhoto(resultKey: String) = FragmentScreen {
         SelectPhotoFragment.getNewInstance(resultKey)
     }
+
+    fun Graph() = ActivityScreen {
+        Intent(it, GraphActivity::class.java)
+    }
 }

sample/src/main/java/com/github/terrakok/cicerone/sample/dagger/AppComponent.kt

@@ -7,6 +7,9 @@ import com.github.terrakok.cicerone.sample.ui.animations.photos.SelectPhotoFragm
 import com.github.terrakok.cicerone.sample.ui.animations.profile.ProfileFragment
 import com.github.terrakok.cicerone.sample.ui.bottom.BottomNavigationActivity
 import com.github.terrakok.cicerone.sample.ui.bottom.TabContainerFragment
+import com.github.terrakok.cicerone.sample.ui.graph.ForkFragment
+import com.github.terrakok.cicerone.sample.ui.graph.GraphActivity
+import com.github.terrakok.cicerone.sample.ui.graph.RoadFragment
 import com.github.terrakok.cicerone.sample.ui.main.MainActivity
 import com.github.terrakok.cicerone.sample.ui.main.SampleFragment
 import com.github.terrakok.cicerone.sample.ui.start.StartActivity
@@ -37,4 +40,10 @@ interface AppComponent {
     fun inject(fragment: SelectPhotoFragment)
 
     fun inject(activity: ProfileActivity)
+
+    fun inject(activity: GraphActivity)
+
+    fun inject(fragment: RoadFragment)
+
+    fun inject(fragment: ForkFragment)
 }

sample/src/main/java/com/github/terrakok/cicerone/sample/dagger/module/NavigationModule.kt

@@ -4,8 +4,11 @@ import com.github.terrakok.cicerone.Cicerone
 import com.github.terrakok.cicerone.Cicerone.Companion.create
 import com.github.terrakok.cicerone.NavigatorHolder
 import com.github.terrakok.cicerone.Router
+import com.github.terrakok.cicerone.graph.GraphRouter
+import com.github.terrakok.cicerone.sample.Graph
 import dagger.Module
 import dagger.Provides
+import javax.inject.Named
 import javax.inject.Singleton
 
 /**
@@ -14,6 +17,7 @@ import javax.inject.Singleton
 @Module
 class NavigationModule {
     private val cicerone: Cicerone<Router> = create()
+    private val graphCicerone: Cicerone<GraphRouter> = create(GraphRouter(Graph()))
 
     @Provides
     @Singleton
@@ -26,4 +30,17 @@ class NavigationModule {
     fun provideNavigatorHolder(): NavigatorHolder {
         return cicerone.getNavigatorHolder()
     }
+
+    @Provides
+    @Singleton
+    fun provideGraphRouter(): GraphRouter {
+        return graphCicerone.router
+    }
+
+    @Provides
+    @Singleton
+    @Named("graph")
+    fun provideGraphNavigatorHolder(): NavigatorHolder {
+        return graphCicerone.getNavigatorHolder()
+    }
 }

sample/src/main/java/com/github/terrakok/cicerone/sample/mvp/graph/ForkPresenter.kt

@@ -0,0 +1,28 @@
+package com.github.terrakok.cicerone.sample.mvp.graph
+
+import com.github.terrakok.cicerone.graph.GraphRouter
+import moxy.InjectViewState
+import moxy.MvpPresenter
+import moxy.MvpView
+
+@InjectViewState
+class ForkPresenter(
+    private val graphRouter: GraphRouter
+): MvpPresenter<MvpView>() {
+
+    fun onTopButtonClick() {
+        graphRouter.currentVertex.edges.firstOrNull()?.id?.let { id ->
+            graphRouter.navigateTo(id)
+        }
+    }
+
+    fun onBottomButtonClick() {
+        graphRouter.currentVertex.edges.lastOrNull()?.id?.let { id ->
+            graphRouter.navigateTo(id)
+        }
+    }
+
+    fun onBackPressed() {
+        graphRouter.exit()
+    }
+}

sample/src/main/java/com/github/terrakok/cicerone/sample/mvp/graph/RoadPresenter.kt

@@ -0,0 +1,28 @@
+package com.github.terrakok.cicerone.sample.mvp.graph
+
+import com.github.terrakok.cicerone.graph.GraphRouter
+import moxy.InjectViewState
+import moxy.MvpPresenter
+import moxy.MvpView
+
+@InjectViewState
+class RoadPresenter(
+    private val graphRouter: GraphRouter
+): MvpPresenter<MvpView>() {
+
+    fun onButtonClick() {
+        graphRouter.currentVertex.edges.firstOrNull()?.id?.let { id ->
+            graphRouter.navigateTo(id)
+        }
+    }
+
+    fun onJumpClick() {
+        graphRouter.currentVertex.jumps.firstOrNull()?.id?.let { id ->
+            graphRouter.jumpTo(id)
+        }
+    }
+
+    fun onBackPressed() {
+        graphRouter.exit()
+    }
+}

sample/src/main/java/com/github/terrakok/cicerone/sample/mvp/start/StartActivityPresenter.kt

@@ -2,6 +2,7 @@ package com.github.terrakok.cicerone.sample.mvp.start
 
 import com.github.terrakok.cicerone.Router
 import com.github.terrakok.cicerone.sample.Screens.BottomNavigation
+import com.github.terrakok.cicerone.sample.Screens.Graph
 import com.github.terrakok.cicerone.sample.Screens.Main
 import com.github.terrakok.cicerone.sample.Screens.Profile
 import moxy.MvpPresenter
@@ -23,6 +24,10 @@ class StartActivityPresenter(private val router: Router) : MvpPresenter<StartAct
         router.navigateTo(Profile())
     }
 
+    fun onGraphPressed() {
+        router.navigateTo(Graph())
+    }
+
     fun onBackPressed() {
         router.exit()
     }

sample/src/main/java/com/github/terrakok/cicerone/sample/ui/graph/ForkFragment.kt

@@ -0,0 +1,65 @@
+package com.github.terrakok.cicerone.sample.ui.graph
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import com.github.terrakok.cicerone.graph.GraphRouter
+import com.github.terrakok.cicerone.sample.SampleApplication
+import com.github.terrakok.cicerone.sample.databinding.FragmentForkBinding
+import com.github.terrakok.cicerone.sample.databinding.FragmentRoadBinding
+import com.github.terrakok.cicerone.sample.mvp.graph.ForkPresenter
+import com.github.terrakok.cicerone.sample.mvp.graph.RoadPresenter
+import com.github.terrakok.cicerone.sample.ui.common.BackButtonListener
+import moxy.MvpAppCompatFragment
+import moxy.MvpView
+import moxy.presenter.InjectPresenter
+import moxy.presenter.ProvidePresenter
+import javax.inject.Inject
+
+class ForkFragment : MvpAppCompatFragment(), MvpView, BackButtonListener {
+    lateinit var binding: FragmentForkBinding
+
+    @Inject
+    lateinit var graphRouter: GraphRouter
+
+    @InjectPresenter
+    lateinit var presenter: ForkPresenter
+
+    @ProvidePresenter
+    fun provideRoadPresenter(): ForkPresenter {
+        return ForkPresenter(graphRouter)
+    }
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        SampleApplication.INSTANCE.appComponent.inject(this)
+        super.onCreate(savedInstanceState)
+    }
+
+    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
+        binding = FragmentForkBinding.inflate(inflater)
+        return binding.root
+    }
+
+    override fun onActivityCreated(savedInstanceState: Bundle?) {
+        super.onActivityCreated(savedInstanceState)
+        binding.textView.text = arguments?.getString(EXTRA_NUMBER)
+        binding.topButton.setOnClickListener { presenter.onTopButtonClick() }
+        binding.bottomButton.setOnClickListener { presenter.onBottomButtonClick()}
+    }
+
+    override fun onBackPressed(): Boolean {
+        presenter.onBackPressed()
+        return true
+    }
+
+    companion object {
+        private const val EXTRA_NUMBER = "extra_number"
+
+        fun getNewInstance(number: String) = ForkFragment().apply {
+            arguments = Bundle().apply {
+                putString(EXTRA_NUMBER, number)
+            }
+        }
+    }
+}

sample/src/main/java/com/github/terrakok/cicerone/sample/ui/graph/GraphActivity.kt

@@ -0,0 +1,63 @@
+package com.github.terrakok.cicerone.sample.ui.graph
+
+import android.os.Bundle
+import android.transition.ChangeBounds
+import androidx.appcompat.app.AppCompatActivity
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.FragmentTransaction
+import com.github.terrakok.cicerone.Command
+import com.github.terrakok.cicerone.Navigator
+import com.github.terrakok.cicerone.NavigatorHolder
+import com.github.terrakok.cicerone.Replace
+import com.github.terrakok.cicerone.androidx.AppNavigator
+import com.github.terrakok.cicerone.graph.GraphRouter
+import com.github.terrakok.cicerone.sample.R
+import com.github.terrakok.cicerone.sample.SampleApplication
+import com.github.terrakok.cicerone.sample.Screens.ProfileInfo
+import com.github.terrakok.cicerone.sample.ui.animations.photos.SelectPhotoFragment
+import com.github.terrakok.cicerone.sample.ui.animations.profile.ProfileFragment
+import com.github.terrakok.cicerone.sample.ui.common.BackButtonListener
+import javax.inject.Inject
+import javax.inject.Named
+
+/**
+ * Created by Konstantin Tskhovrebov (aka @terrakok) on 14.07.17.
+ */
+class GraphActivity : AppCompatActivity() {
+
+    @Inject
+    @Named("graph")
+    lateinit var navigatorHolder: NavigatorHolder
+
+    @Inject
+    lateinit var graphRouter: GraphRouter
+
+    private val navigator = AppNavigator(this, R.id.container)
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        SampleApplication.INSTANCE.appComponent.inject(this)
+        super.onCreate(savedInstanceState)
+
+        setContentView(R.layout.activity_container)
+    }
+
+    override fun onResumeFragments() {
+        super.onResumeFragments()
+        navigatorHolder.setNavigator(navigator)
+    }
+
+    override fun onPause() {
+        navigatorHolder.removeNavigator()
+        super.onPause()
+    }
+
+    override fun onBackPressed() {
+        val fragment = supportFragmentManager.findFragmentById(R.id.container)
+        if (fragment != null && fragment is BackButtonListener
+                && (fragment as BackButtonListener).onBackPressed()) {
+            return
+        } else {
+            super.onBackPressed()
+        }
+    }
+}

sample/src/main/java/com/github/terrakok/cicerone/sample/ui/graph/RoadFragment.kt

@@ -0,0 +1,63 @@
+package com.github.terrakok.cicerone.sample.ui.graph
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import com.github.terrakok.cicerone.graph.GraphRouter
+import com.github.terrakok.cicerone.sample.SampleApplication
+import com.github.terrakok.cicerone.sample.databinding.FragmentRoadBinding
+import com.github.terrakok.cicerone.sample.mvp.graph.RoadPresenter
+import com.github.terrakok.cicerone.sample.ui.common.BackButtonListener
+import moxy.MvpAppCompatFragment
+import moxy.MvpView
+import moxy.presenter.InjectPresenter
+import moxy.presenter.ProvidePresenter
+import javax.inject.Inject
+
+class RoadFragment : MvpAppCompatFragment(), MvpView, BackButtonListener {
+    lateinit var binding: FragmentRoadBinding
+
+    @Inject
+    lateinit var graphRouter: GraphRouter
+
+    @InjectPresenter
+    lateinit var presenter: RoadPresenter
+
+    @ProvidePresenter
+    fun provideRoadPresenter(): RoadPresenter {
+        return RoadPresenter(graphRouter)
+    }
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        SampleApplication.INSTANCE.appComponent.inject(this)
+        super.onCreate(savedInstanceState)
+    }
+
+    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
+        binding = FragmentRoadBinding.inflate(inflater)
+        return binding.root
+    }
+
+    override fun onActivityCreated(savedInstanceState: Bundle?) {
+        super.onActivityCreated(savedInstanceState)
+        binding.textView.text = arguments?.getString(EXTRA_NUMBER)
+        binding.forwardButton.setOnClickListener { presenter.onButtonClick() }
+        binding.jumpButton.setOnClickListener { presenter.onJumpClick() }
+    }
+
+    override fun onBackPressed(): Boolean {
+        presenter.onBackPressed()
+        return true
+    }
+
+    companion object {
+        private const val EXTRA_NUMBER = "extra_number"
+
+        fun getNewInstance(number: String) = RoadFragment().apply {
+            arguments = Bundle().apply {
+                putString(EXTRA_NUMBER, number)
+            }
+        }
+    }
+}

sample/src/main/java/com/github/terrakok/cicerone/sample/ui/start/StartActivity.kt

@@ -52,6 +52,9 @@ class StartActivity : MvpAppCompatActivity(), StartActivityView {
         findViewById<View>(R.id.result_and_anim_button).setOnClickListener {
             presenter.onResultWithAnimationPressed()
         }
+        findViewById<View>(R.id.graph_button).setOnClickListener {
+            presenter.onGraphPressed()
+        }
     }
 
     override fun onResume() {

sample/src/main/res/layout/activity_start.xml

@@ -43,4 +43,11 @@
         android:layout_height="wrap_content"
         android:layout_margin="16dp"
         android:text="@string/result_and_anim_nav"/>
+
+    <Button
+        android:id="@+id/graph_button"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_margin="16dp"
+        android:text="@string/graph_nav"/>
 </LinearLayout>

sample/src/main/res/layout/fragment_fork.xml

@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+              android:layout_width="match_parent"
+              android:layout_height="match_parent"
+              android:orientation="vertical">
+
+    <Space
+        android:layout_width="wrap_content"
+        android:layout_height="0dp"
+        android:layout_weight="1"/>
+
+    <TextView
+        android:id="@+id/textView"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:gravity="center"
+        android:padding="16dp"
+        android:textColor="@android:color/white"
+        android:textSize="13sp"/>
+
+    <Button
+        android:id="@+id/top_button"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center"
+        android:minWidth="100dp"
+        android:text="➔"
+        android:textSize="20sp"/>
+
+    <Button
+        android:id="@+id/bottom_button"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center"
+        android:minWidth="100dp"
+        android:text="➔"
+        android:textSize="20sp"/>
+
+    <Space
+        android:layout_width="wrap_content"
+        android:layout_height="0dp"
+        android:layout_weight="1"/>
+</LinearLayout>

sample/src/main/res/layout/fragment_road.xml

@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+              android:layout_width="match_parent"
+              android:layout_height="match_parent"
+              android:orientation="vertical">
+
+    <Space
+        android:layout_width="wrap_content"
+        android:layout_height="0dp"
+        android:layout_weight="1"/>
+
+    <TextView
+        android:id="@+id/textView"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:gravity="center"
+        android:padding="16dp"
+        android:textColor="@android:color/white"
+        android:textSize="13sp"/>
+
+    <Button
+        android:id="@+id/forward_button"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center"
+        android:minWidth="100dp"
+        android:text="➔"
+        android:textSize="20sp"/>
+
+    <Button
+        android:id="@+id/jump_button"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center"
+        android:minWidth="100dp"
+        android:text="JUMP"
+        android:textSize="20sp"/>
+
+    <Space
+        android:layout_width="wrap_content"
+        android:layout_height="0dp"
+        android:layout_weight="1"/>
+</LinearLayout>

sample/src/main/res/values/strings.xml

@@ -4,6 +4,7 @@
     <string name="ordinary_nav">Ordinary navigation</string>
     <string name="multi_nav">Multi navigation</string>
     <string name="result_and_anim_nav">Resulting and animation sample</string>
+    <string name="graph_nav">Navigation graph</string>
 
     <string name="tab_android">Android</string>
     <string name="tab_bug">Bug</string>