Remove react hacks

This commit removes necessary hacks which were introduced due to
limitations of previous React Native apis.

Mount/unmount logic isn't coupled to view attached/detached
to window callbacks. Instead, `unmountReactApplication` was added.
We can safely call it when a screen is popped and when application is
reloaded in debug.

android/app/src/main/java/com/reactnativenavigation/react/ReactViewHacks.java

@@ -1,26 +0,0 @@
-package com.reactnativenavigation.react;
-
-import com.facebook.react.ReactRootView;
-import com.reactnativenavigation.utils.ReflectionUtils;
-
-public class ReactViewHacks {
-
-    public static void preventUnmountOnDetachedFromWindow(ReactRootView view) {
-        ReflectionUtils.setField(view, "mAttachScheduled", true);
-    }
-
-    /**
-     * Side effect: prevents JS components constructor from being called
-     */
-    public static void ensureUnmountOnDetachedFromWindow(ReactRootView view) {
-        ReflectionUtils.setField(view, "mAttachScheduled", false);
-    }
-
-    /**
-     * Side effect: ensures unmount will be called
-     */
-    public static void preventMountAfterReattachedToWindow(ReactRootView view) {
-        ReflectionUtils.setField(view, "mAttachScheduled", false);
-    }
-
-}

android/app/src/main/java/com/reactnativenavigation/screens/FragmentScreen.java

@@ -109,17 +109,7 @@ public class FragmentScreen extends Screen {
     }
 
     @Override
-    public void ensureUnmountOnDetachedFromWindow() {
-        // nothing
-    }
-
-    @Override
-    public void preventUnmountOnDetachedFromWindow() {
-        // nothing
-    }
-
-    @Override
-    public void preventMountAfterReattachedToWindow() {
+    public void unmountOnDetachedFromWindow() {
         // nothing
     }
 

android/app/src/main/java/com/reactnativenavigation/screens/Screen.java

@@ -122,11 +122,7 @@ public abstract class Screen extends RelativeLayout {
         }
     }
 
-    public abstract void ensureUnmountOnDetachedFromWindow();
-
-    public abstract void preventUnmountOnDetachedFromWindow();
-
-    public abstract void preventMountAfterReattachedToWindow();
+    public abstract void unmountOnDetachedFromWindow();
 
     public String getScreenInstanceId() {
         return screenParams.getScreenInstanceId();

android/app/src/main/java/com/reactnativenavigation/screens/ScreenStack.java

@@ -87,7 +87,7 @@ public class ScreenStack {
                 nextScreen.show(nextScreen.screenParams.animateScreenTransitions, new Runnable() {
                     @Override
                     public void run() {
-                        removePreviousWithoutUnmount(previousScreen);
+                        parent.removeView(previousScreen);
                     }
                 });
             }
@@ -97,7 +97,7 @@ public class ScreenStack {
     private void pushScreenToInvisibleStack(LayoutParams layoutParams, Screen nextScreen, Screen previousScreen) {
         nextScreen.setVisibility(View.INVISIBLE);
         addScreen(nextScreen, layoutParams);
-        removePreviousWithoutUnmount(previousScreen);
+        parent.removeView(previousScreen);
     }
 
     private void addScreen(Screen screen, LayoutParams layoutParams) {
@@ -109,11 +109,6 @@ public class ScreenStack {
         parent.addView(screen, parent.getChildCount() - 1, layoutParams);
     }
 
-    private void removePreviousWithoutUnmount(Screen previous) {
-        previous.preventUnmountOnDetachedFromWindow();
-        parent.removeView(previous);
-    }
-
     public void pop(boolean animated) {
         pop(animated, null);
     }
@@ -146,7 +141,7 @@ public class ScreenStack {
         toRemove.hide(animated, new Runnable() {
             @Override
             public void run() {
-                toRemove.ensureUnmountOnDetachedFromWindow();
+                toRemove.unmountOnDetachedFromWindow();
                 parent.removeView(toRemove);
             }
         });
@@ -163,7 +158,6 @@ public class ScreenStack {
     private void readdPrevious(Screen previous) {
         previous.setVisibility(View.VISIBLE);
         parent.addView(previous, 0);
-        previous.preventMountAfterReattachedToWindow();
     }
 
     public void popToRoot(boolean animated) {
@@ -174,7 +168,7 @@ public class ScreenStack {
 
     public void destroy() {
         for (Screen screen : stack) {
-            screen.ensureUnmountOnDetachedFromWindow();
+            screen.unmountOnDetachedFromWindow();
             parent.removeView(screen);
         }
         stack.clear();

android/app/src/main/java/com/reactnativenavigation/screens/SingleScreen.java

@@ -28,18 +28,8 @@ public class SingleScreen extends Screen {
     }
 
     @Override
-    public void ensureUnmountOnDetachedFromWindow() {
-        contentView.ensureUnmountOnDetachedFromWindow();
-    }
-
-    @Override
-    public void preventUnmountOnDetachedFromWindow() {
-        contentView.preventUnmountOnDetachedFromWindow();
-    }
-
-    @Override
-    public void preventMountAfterReattachedToWindow() {
-        contentView.preventMountAfterReattachedToWindow();
+    public void unmountOnDetachedFromWindow() {
+        contentView.unmountOnDetachedFromWindow();
     }
 
     @Override

android/app/src/main/java/com/reactnativenavigation/screens/ViewPagerScreen.java

@@ -64,23 +64,9 @@ public class ViewPagerScreen extends Screen {
     }
 
     @Override
-    public void ensureUnmountOnDetachedFromWindow() {
+    public void unmountOnDetachedFromWindow() {
         for (ContentView contentView : contentViews) {
-            contentView.ensureUnmountOnDetachedFromWindow();
-        }
-    }
-
-    @Override
-    public void preventUnmountOnDetachedFromWindow() {
-        for (ContentView contentView : contentViews) {
-            contentView.preventUnmountOnDetachedFromWindow();
-        }
-    }
-
-    @Override
-    public void preventMountAfterReattachedToWindow() {
-        for (ContentView contentView : contentViews) {
-            contentView.preventMountAfterReattachedToWindow();
+            contentView.unmountOnDetachedFromWindow();
         }
     }
 

android/app/src/main/java/com/reactnativenavigation/views/ContentView.java

@@ -6,7 +6,6 @@ import android.view.View;
 import com.facebook.react.ReactRootView;
 import com.reactnativenavigation.NavigationApplication;
 import com.reactnativenavigation.params.NavigationParams;
-import com.reactnativenavigation.react.ReactViewHacks;
 import com.reactnativenavigation.screens.SingleScreen;
 import com.reactnativenavigation.utils.ViewUtils;
 
@@ -29,16 +28,8 @@ public class ContentView extends ReactRootView {
         return navigationParams.navigatorEventId;
     }
 
-    public void preventUnmountOnDetachedFromWindow() {
-        ReactViewHacks.preventUnmountOnDetachedFromWindow(this);
-    }
-
-    public void ensureUnmountOnDetachedFromWindow() {
-        ReactViewHacks.ensureUnmountOnDetachedFromWindow(this);
-    }
-
-    public void preventMountAfterReattachedToWindow() {
-        ReactViewHacks.preventMountAfterReattachedToWindow(this);
+    public void unmountOnDetachedFromWindow() {
+        unmountReactApplication();
     }
 
     @Override

android/app/src/main/java/com/reactnativenavigation/views/SideMenu.java

@@ -19,7 +19,7 @@ public class SideMenu extends DrawerLayout {
     }
 
     public void destroy() {
-        sideMenuView.ensureUnmountOnDetachedFromWindow();
+        sideMenuView.unmountOnDetachedFromWindow();
         removeView(sideMenuView);
     }