feat(Android): restore default Android animations

android/src/main/java/com/swmansion/rnscreens/Screen.kt

@@ -278,4 +278,10 @@ class Screen(context: ReactContext?) : FabricEnabledViewGroup(context) {
     enum class WindowTraits {
         ORIENTATION, COLOR, STYLE, TRANSLUCENT, HIDDEN, ANIMATED, NAVIGATION_BAR_COLOR, NAVIGATION_BAR_HIDDEN
     }
+
+    companion object {
+        fun isSystemAnimation(stackAnimation: StackAnimation): Boolean {
+            return stackAnimation === StackAnimation.DEFAULT || stackAnimation === StackAnimation.FADE || stackAnimation === StackAnimation.NONE
+        }
+    }
 }

android/src/main/java/com/swmansion/rnscreens/ScreenFragment.kt

@@ -272,7 +272,7 @@ open class ScreenFragment : Fragment, ScreenFragmentWrapper {
             // onViewAnimationStart/End is triggered from View#onAnimationStart/End method of the fragment's root
             // view. We override an appropriate method of the StackFragment's
             // root view in order to achieve this.
-            if (isResumed) {
+            if (isResumed || screen.container?.topScreen === screen) {
                 // Android dispatches the animation start event for the fragment that is being added first
                 // however we want the one being dismissed first to match iOS. It also makes more sense from
                 // a navigation point of view to have the disappear event first.

android/src/main/java/com/swmansion/rnscreens/ScreenStack.kt

@@ -4,13 +4,12 @@ import android.content.Context
 import android.graphics.Canvas
 import android.os.Build
 import android.view.View
+import androidx.fragment.app.FragmentTransaction
 import com.facebook.react.bridge.ReactContext
 import com.facebook.react.uimanager.UIManagerHelper
 import com.swmansion.rnscreens.Screen.StackAnimation
 import com.swmansion.rnscreens.events.StackFinishTransitioningEvent
 import java.util.Collections
-import kotlin.collections.ArrayList
-import kotlin.collections.HashSet
 
 class ScreenStack(context: Context?) : ScreenContainer(context) {
     private val stack = ArrayList<ScreenStackFragmentWrapper>()
@@ -139,9 +138,9 @@ class ScreenStack(context: Context?) : ScreenContainer(context) {
             if (stackAnimation != null) {
                 if (shouldUseOpenAnimation) {
                     when (stackAnimation) {
-                        StackAnimation.DEFAULT -> it.setCustomAnimations(R.anim.rns_default_enter_in, R.anim.rns_default_enter_out)
-                        StackAnimation.NONE -> it.setCustomAnimations(R.anim.rns_no_animation_20, R.anim.rns_no_animation_20)
-                        StackAnimation.FADE -> it.setCustomAnimations(R.anim.rns_fade_in, R.anim.rns_fade_out)
+                        StackAnimation.DEFAULT -> it.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN)
+                        StackAnimation.NONE -> it.setTransition(FragmentTransaction.TRANSIT_NONE)
+                        StackAnimation.FADE -> it.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE)
                         StackAnimation.SLIDE_FROM_RIGHT -> it.setCustomAnimations(R.anim.rns_slide_in_from_right, R.anim.rns_slide_out_to_left)
                         StackAnimation.SLIDE_FROM_LEFT -> it.setCustomAnimations(R.anim.rns_slide_in_from_left, R.anim.rns_slide_out_to_right)
                         StackAnimation.SLIDE_FROM_BOTTOM -> it.setCustomAnimations(
@@ -152,9 +151,9 @@ class ScreenStack(context: Context?) : ScreenContainer(context) {
                     }
                 } else {
                     when (stackAnimation) {
-                        StackAnimation.DEFAULT -> it.setCustomAnimations(R.anim.rns_default_exit_in, R.anim.rns_default_exit_out)
-                        StackAnimation.NONE -> it.setCustomAnimations(R.anim.rns_no_animation_20, R.anim.rns_no_animation_20)
-                        StackAnimation.FADE -> it.setCustomAnimations(R.anim.rns_fade_in, R.anim.rns_fade_out)
+                        StackAnimation.DEFAULT -> it.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_CLOSE)
+                        StackAnimation.NONE -> it.setTransition(FragmentTransaction.TRANSIT_NONE)
+                        StackAnimation.FADE -> it.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE)
                         StackAnimation.SLIDE_FROM_RIGHT -> it.setCustomAnimations(R.anim.rns_slide_in_from_left, R.anim.rns_slide_out_to_right)
                         StackAnimation.SLIDE_FROM_LEFT -> it.setCustomAnimations(R.anim.rns_slide_in_from_right, R.anim.rns_slide_out_to_left)
                         StackAnimation.SLIDE_FROM_BOTTOM -> it.setCustomAnimations(

android/src/main/java/com/swmansion/rnscreens/ScreenStackFragment.kt

@@ -1,5 +1,9 @@
 package com.swmansion.rnscreens
 
+import android.animation.Animator
+import android.animation.AnimatorInflater
+import android.animation.AnimatorListenerAdapter
+import android.animation.AnimatorSet
 import android.annotation.SuppressLint
 import android.content.Context
 import android.graphics.Color
@@ -16,6 +20,9 @@ import android.view.animation.Transformation
 import android.widget.LinearLayout
 import androidx.appcompat.widget.Toolbar
 import androidx.coordinatorlayout.widget.CoordinatorLayout
+import androidx.fragment.R
+import androidx.fragment.app.FragmentTransaction
+import com.facebook.react.bridge.UiThreadUtil
 import com.facebook.react.uimanager.PixelUtil
 import com.google.android.material.appbar.AppBarLayout
 import com.google.android.material.appbar.AppBarLayout.ScrollingViewBehavior
@@ -86,6 +93,53 @@ class ScreenStackFragment : ScreenFragment, ScreenStackFragmentWrapper {
         notifyViewAppearTransitionEnd()
     }
 
+    // Similarly to ScreensCoordinatorLayout, this method listens only for the phases of default Android
+    // transitions (default/none/fade), since `ScreensCoordinatorLayout#startAnimation` is being
+    // called only for custom animations.
+    override fun onCreateAnimator(transit: Int, enter: Boolean, nextAnim: Int): Animator? {
+        val listener = object : AnimatorListenerAdapter() {
+            override fun onAnimationStart(animation: Animator) {
+                onViewAnimationStart()
+                super.onAnimationStart(animation)
+            }
+
+            override fun onAnimationEnd(animation: Animator) {
+                onViewAnimationEnd()
+                super.onAnimationEnd(animation)
+            }
+        }
+
+        // If there's custom animation set, use default onCreateAnimator implementation, as event
+        // handling will be handled by ScreensCoordinatorLayout.
+        if (!Screen.isSystemAnimation(screen.stackAnimation)) {
+            return super.onCreateAnimator(transit, enter, nextAnim)
+        }
+
+        // When fragment is being removed or there's no transition selected, we simply
+        // return AnimatorSet without any animation.
+        if (isRemoving || transit == FragmentTransaction.TRANSIT_NONE) {
+            return AnimatorSet().apply {
+                addListener(listener)
+            }
+        }
+
+        var selectedNextAnim = nextAnim
+        if (nextAnim == 0) {
+            selectedNextAnim = when (transit) {
+                FragmentTransaction.TRANSIT_FRAGMENT_OPEN -> if (enter) R.animator.fragment_open_enter else R.animator.fragment_open_exit
+                FragmentTransaction.TRANSIT_FRAGMENT_CLOSE -> if (enter) R.animator.fragment_close_enter else R.animator.fragment_close_exit
+                FragmentTransaction.TRANSIT_FRAGMENT_FADE -> if (enter) R.animator.fragment_fade_enter else R.animator.fragment_fade_exit
+                else -> 0
+            }
+        }
+
+        val animator = AnimatorInflater.loadAnimator(context, selectedNextAnim).apply {
+            addListener(listener)
+        }
+
+        return animator
+    }
+
     private fun notifyViewAppearTransitionEnd() {
         val screenStack = view?.parent
         if (screenStack is ScreenStack) {