Fixed resumed child bug

ikarenkov · ikarenkov · Nov 16, 2024 · Nov 6, 2024 · Nov 11, 2024 · Nov 16, 2024
commit 4b15c7c9a0016e58558d5501d9f6bf0a1f938999
diff --git a/modo-compose/src/main/java/com/github/terrakok/modo/android/ModoScreenAndroidAdapter.kt b/modo-compose/src/main/java/com/github/terrakok/modo/android/ModoScreenAndroidAdapter.kt
@@ -100,6 +100,12 @@ class ModoScreenAndroidAdapter private constructor(
     private val atomicParentLifecycleOwner = AtomicReference<LifecycleOwner>()
     private val application: Application? get() = atomicContext.get()?.applicationContext?.getApplication()
 
+    /**
+     * Indicates that lifecycle should be moved to RESUMED state as soon as parent will be RESUMED.
+     */
+    @Volatile
+    private var isResumePostponed: Boolean = false
+
     init {
         controller.performAttach()
         enableSavedStateHandles()
@@ -135,7 +141,15 @@ class ModoScreenAndroidAdapter private constructor(
     }
 
     override fun onResume() {
-        safeHandleLifecycleEvent(ON_RESUME)
+        val parentState = atomicParentLifecycleOwner.get()?.lifecycle?.currentState
+        if (parentState == null || parentState != Lifecycle.State.RESUMED) {
+            // We need to do so, because child is ready to move to resumed state, when parent is not.
+            // It can happen when we display this screen as a first screen inside container, that is animating.
+            // So we need to wait until parent will be resumed and execute ON_RESUME event after it.
+            isResumePostponed = true
+        } else {
+            safeHandleLifecycleEvent(ON_RESUME)
+        }
     }
 
     override fun toString(): String = "${ModoScreenAndroidAdapter::class.simpleName}, screenKey: ${screen.screenKey}"
@@ -239,10 +253,15 @@ class ModoScreenAndroidAdapter private constructor(
                     if (
                         needPropagateLifecycleEventFromParent(
                             event,
+                            isResumePostponed = isResumePostponed,
                             isActivityFinishing = activity?.isFinishing,
                             isChangingConfigurations = activity?.isChangingConfigurations
                         )
                     ) {
+                        // reset postpone resume flag because we moved state to resumed
+                        if (event == ON_RESUME) {
+                            isResumePostponed = false
+                        }
                         safeHandleLifecycleEvent(event)
                     }
                 }
@@ -298,6 +317,7 @@ class ModoScreenAndroidAdapter private constructor(
         @JvmStatic
         fun needPropagateLifecycleEventFromParent(
             event: Lifecycle.Event,
+            isResumePostponed: Boolean,
             isActivityFinishing: Boolean?,
             isChangingConfigurations: Boolean?
         ) =
@@ -312,11 +332,17 @@ class ModoScreenAndroidAdapter private constructor(
              *
              * In the case of Fragments, we unsubscribe before ON_DESTROY event, so there is no problem with this.
              */
-            if (event == ON_DESTROY && (isActivityFinishing == false || isChangingConfigurations == true)) {
-                false
-            } else {
-                // Parent can only move lifecycle state down. Because parent cant be already resumed, but child is not, because of running animation.
-                event !in moveLifecycleStateUpEvents
+            when {
+                event == ON_DESTROY && (isActivityFinishing == false || isChangingConfigurations == true) -> {
+                    false
+                }
+                isResumePostponed && event == ON_RESUME -> {
+                    true
+                }
+                else -> {
+                    // Parent can only move lifecycle state down. Because parent cant be already resumed, but child is not, because of running animation.
+                    event !in moveLifecycleStateUpEvents
+                }
             }
 
         @JvmStatic

diff --git a/modo-compose/src/main/java/com/github/terrakok/modo/stack/StackState.kt b/modo-compose/src/main/java/com/github/terrakok/modo/stack/StackState.kt
@@ -10,8 +10,9 @@ import kotlinx.parcelize.Parcelize
 
 typealias StackNavModel = NavModel<StackState, StackAction>
 
-fun StackNavModel(stack: List<Screen>) = StackNavModel(StackState(stack))
-fun StackNavModel(screen: Screen) = StackNavModel(listOf(screen))
+fun StackNavModel(stack: List<Screen>): StackNavModel = StackNavModel(StackState(stack))
+fun StackNavModel(screen: Screen): StackNavModel = StackNavModel(listOf(screen))
+fun StackNavModel(vararg screens: Screen): StackNavModel = StackNavModel(screens.toList())
 
 @Stable
 interface StackNavContainer : NavigationContainer<StackState, StackAction>

diff --git a/sample/src/main/java/com/github/terrakok/modo/sample/screens/MainScreen.kt b/sample/src/main/java/com/github/terrakok/modo/sample/screens/MainScreen.kt
@@ -32,6 +32,7 @@ import com.github.terrakok.modo.sample.screens.stack.StackActionsScreen
 import com.github.terrakok.modo.sample.screens.viewmodel.AndroidViewModelSampleScreen
 import com.github.terrakok.modo.stack.LocalStackNavigation
 import com.github.terrakok.modo.stack.StackNavContainer
+import com.github.terrakok.modo.stack.StackNavModel
 import com.github.terrakok.modo.stack.back
 import com.github.terrakok.modo.stack.forward
 import com.github.terrakok.modo.util.getActivity
@@ -164,6 +165,25 @@ private fun rememberButtons(
                     buttons = listOf(
                         ModoButtonSpec("Screen Lifecycle") { navigation?.forward(LifecycleSampleScreen(i + 1)) },
                         ModoButtonSpec("Keyboard + Lifecycle") { navigation?.forward(KeyboardWithLifecycleScreen()) },
+                        ModoButtonSpec("Open predefined flow") {
+                            navigation?.forward(
+                                CustomStackSample(
+                                    i + 1,
+                                    StackNavModel(
+                                        MainScreen(i + 2),
+                                        MainScreen(i + 3),
+                                        KeyboardWithLifecycleScreen(),
+                                        CustomStackSample(
+                                            i = i + 4,
+                                            navModel = StackNavModel(
+                                                MainScreen(i + 5),
+                                                KeyboardWithLifecycleScreen(),
+                                            ),
+                                        ),
+                                    )
+                                )
+                            )
+                        },
                     )
                 ),
                 GroupedButtonsState.Group(

diff --git a/...ain/java/com/github/terrakok/modo/sample/screens/lifecycle/KeyboardWithLifecycleScreen.kt b/...ain/java/com/github/terrakok/modo/sample/screens/lifecycle/KeyboardWithLifecycleScreen.kt
@@ -24,6 +24,7 @@ import com.github.terrakok.modo.ScreenKey
 import com.github.terrakok.modo.generateScreenKey
 import com.github.terrakok.modo.sample.screens.ModoButton
 import com.github.terrakok.modo.sample.screens.ModoButtonSpec
+import com.github.terrakok.modo.sample.screens.base.LogLifecycle
 import com.github.terrakok.modo.stack.LocalStackNavigation
 import com.github.terrakok.modo.stack.back
 import com.github.terrakok.modo.util.getActivity
@@ -39,6 +40,7 @@ class KeyboardWithLifecycleScreen(
 ) : Screen {
     @Composable
     override fun Content(modifier: Modifier) {
+        LogLifecycle()
         Column(modifier.windowInsetsPadding(WindowInsets.systemBars)) {
             val stackNavigation = LocalStackNavigation.current
             ModoButton(ModoButtonSpec("Back") { stackNavigation.back() })