Support react-native-youtube (#5903)

react-native-youtubte is a popular library which wraps the native youtube library. The native lib attempts to detect if the player is hidden behind other views in order to prevent developers from playing videos in the background.
Since the overlay container was always attached to hierarchy, the library stopped playback as it mistakingly detected the player was used in the background.

This commit simply attaches the overlay container only when needed so as long as no overlays are displayed, the lib can be used.

lib/android/app/src/main/java/com/reactnativenavigation/presentation/OverlayManager.java

 package com.reactnativenavigation.presentation;
 
+import android.view.View;
 import android.view.ViewGroup;
 
 import com.reactnativenavigation.utils.CommandListener;
+import com.reactnativenavigation.utils.ViewUtils;
 import com.reactnativenavigation.viewcontrollers.ViewController;
 import com.reactnativenavigation.views.BehaviourDelegate;
 
 import java.util.HashMap;
 
+import static com.reactnativenavigation.utils.CollectionUtils.*;
 import static com.reactnativenavigation.utils.CoordinatorLayoutUtils.matchParentWithBehaviour;
 
 public class OverlayManager {
     private final HashMap<String, ViewController> overlayRegistry = new HashMap<>();
+    private ViewGroup contentLayout;
+
+    public void setContentLayout(ViewGroup contentLayout) {
+        this.contentLayout = contentLayout;
+    }
 
     public void show(ViewGroup overlaysContainer, ViewController overlay, CommandListener listener) {
+        if (overlaysContainer.getParent() == null) contentLayout.addView(overlaysContainer);
         overlayRegistry.put(overlay.getId(), overlay);
         overlay.addOnAppearedListener(() -> listener.onSuccess(overlay.getId()));
         overlaysContainer.addView(overlay.getView(), matchParentWithBehaviour(new BehaviourDelegate(overlay)));
         if (overlay == null) {
             listener.onError("Could not dismiss Overlay. Overlay with id " + componentId + " was not found.");
         } else {
-            overlay.destroy();
-            overlayRegistry.remove(componentId);
+            destroyOverlay(overlay);
             listener.onSuccess(componentId);
         }
     }
 
     public void destroy() {
-        for (ViewController view : overlayRegistry.values()) {
-            view.destroy();
-        }
-        overlayRegistry.clear();
+        forEach(overlayRegistry.values(), this::destroyOverlay);
+        contentLayout = null;
     }
 
     public int size() {
     public ViewController findControllerById(String id) {
         return overlayRegistry.get(id);
     }
+
+    private void destroyOverlay(ViewController overlay) {
+        View parent = (View) overlay.getView().getParent();
+        overlay.destroy();
+        overlayRegistry.remove(overlay.getId());
+        if (isEmpty()) ViewUtils.removeFromParent(parent);
+    }
+
+    private boolean isEmpty() {
+        return size() == 0;
+    }
 }

lib/android/app/src/main/java/com/reactnativenavigation/viewcontrollers/navigator/Navigator.java

 
     public void setContentLayout(ViewGroup contentLayout) {
         this.contentLayout = contentLayout;
+        overlayManager.setContentLayout(contentLayout);
         contentLayout.addView(rootLayout);
         contentLayout.addView(modalsLayout);
-        contentLayout.addView(overlaysLayout);
     }
 
     public Navigator(final Activity activity, ChildControllersRegistry childRegistry, ModalStack modalStack, OverlayManager overlayManager, RootPresenter rootPresenter) {

lib/android/app/src/test/java/com/reactnativenavigation/viewcontrollers/navigator/NavigatorTest.java

 
 import android.os.Bundle;
 import android.view.View;
+import android.view.ViewGroup;
 import android.widget.FrameLayout;
 
 import com.facebook.react.ReactInstanceManager;
         activityController.postCreate(Bundle.EMPTY);
     }
 
+    @Test
+    public void setContentLayout() {
+        ViewGroup contentLayout = Mockito.mock(ViewGroup.class);
+        uut.setContentLayout(contentLayout);
+
+        verify(overlayManager).setContentLayout(contentLayout);
+    }
+
     @Test
     public void bindViews() {
         verify(rootPresenter).setRootContainer(uut.getRootLayout());
     @Test
     public void setRoot_clearsSplashLayout() {
         FrameLayout content = activity.findViewById(android.R.id.content);
-        assertThat(content.getChildCount()).isEqualTo(4); // 3 frame layouts and the default splash layout
+        assertThat(content.getChildCount()).isEqualTo(3); // 2 frame layouts (root and modal containers) and the default splash layout
 
         uut.setRoot(child2, new CommandListenerAdapter(), reactInstanceManager);
 
-        assertThat(content.getChildCount()).isEqualTo(3);
+        assertThat(content.getChildCount()).isEqualTo(2);
     }
 
     @Test

lib/android/app/src/test/java/com/reactnativenavigation/viewcontrollers/overlay/OverlayManagerTest.java

     private OverlayManager uut;
     private SimpleViewController overlay1;
     private SimpleViewController overlay2;
-    private FrameLayout root;
+    private FrameLayout contentLayout;
+    private FrameLayout overlayContainer;
 
     @Override
     public void beforeEach() {
         Activity activity = newActivity();
-        root = new FrameLayout(activity);
-        root.layout(0, 0, 1000, 1000);
-        activity.setContentView(root);
+        contentLayout = new FrameLayout(activity);
+        contentLayout.layout(0, 0, 1000, 1000);
+        activity.setContentView(contentLayout);
+        overlayContainer = new FrameLayout(activity);
 
         ChildControllersRegistry childRegistry = new ChildControllersRegistry();
         overlay1 = spy(new SimpleViewController(activity, childRegistry, OVERLAY_ID_1, new Options()));
         overlay2 = spy(new SimpleViewController(activity, childRegistry, OVERLAY_ID_2, new Options()));
         uut = new OverlayManager();
+        uut.setContentLayout(contentLayout);
+    }
+
+    @Test
+    public void show_attachesOverlayContainerToContentLayout() {
+        uut.show(overlayContainer, overlay1, new CommandListenerAdapter());
+        assertThat(overlayContainer.getParent()).isEqualTo(contentLayout);
+        uut.show(overlayContainer, overlay2, new CommandListenerAdapter());
     }
 
     @Test
     public void show() {
         CommandListenerAdapter listener = spy(new CommandListenerAdapter());
-        uut.show(root, overlay1, listener);
+        uut.show(overlayContainer, overlay1, listener);
         verify(listener, times(1)).onSuccess(OVERLAY_ID_1);
-        assertThat(overlay1.getView().getParent()).isEqualTo(root);
+        assertThat(overlay1.getView().getParent()).isEqualTo(overlayContainer);
         assertMatchParent(overlay1.getView());
     }
 
     @Test
     public void dismiss() {
-        uut.show(root, overlay1, new CommandListenerAdapter());
+        uut.show(overlayContainer, overlay1, new CommandListenerAdapter());
         assertThat(uut.size()).isOne();
         CommandListener listener = spy(new CommandListenerAdapter());
         uut.dismiss(overlay1.getId(), listener);
 
     @Test
     public void dismiss_onViewReturnedToFront() {
-        uut.show(root, overlay1, new CommandListenerAdapter());
-        uut.show(root, overlay2, new CommandListenerAdapter());
+        uut.show(overlayContainer, overlay1, new CommandListenerAdapter());
+        uut.show(overlayContainer, overlay2, new CommandListenerAdapter());
         verify(overlay1, times(0)).onViewBroughtToFront();
 
         uut.dismiss(OVERLAY_ID_2, new CommandListenerAdapter());
         verify(overlay1, times(1)).onViewBroughtToFront();
     }
+
+    @Test
+    public void dismiss_overlayContainerIsRemovedIfAllOverlaysAreDismissed() {
+        uut.show(overlayContainer, overlay1, new CommandListenerAdapter());
+        uut.show(overlayContainer, overlay2, new CommandListenerAdapter());
+
+        uut.dismiss(OVERLAY_ID_2, new CommandListenerAdapter());
+        assertThat(overlayContainer.getParent()).isEqualTo(contentLayout);
+        uut.dismiss(OVERLAY_ID_1, new CommandListenerAdapter());
+        assertThat(overlayContainer.getParent()).isNull();
+    }
 }