Fix popToRoot when keyboard is visible (#655)

* Fix bug in popToRoot when keyboard is visible

* Add comments

* code review changes

* Add final to function parameters

android/app/src/main/java/com/reactnativenavigation/layouts/BottomTabsLayout.java

             @Override
             public void onScreenPopAnimationEnd() {
                 setBottomTabsStyleFromCurrentScreen();
+                EventBus.instance.post(new ScreenChangedEvent(getCurrentScreenStack().peek().getScreenParams()));
             }
         });
-        EventBus.instance.post(new ScreenChangedEvent(getCurrentScreenStack().peek().getScreenParams()));
     }
 
     @Override
     public void popToRoot(ScreenParams params) {
-        getCurrentScreenStack().popToRoot(params.animateScreenTransitions);
-        setBottomTabsStyleFromCurrentScreen();
-        EventBus.instance.post(new ScreenChangedEvent(getCurrentScreenStack().peek().getScreenParams()));
+        getCurrentScreenStack().popToRoot(params.animateScreenTransitions, new ScreenStack.OnScreenPop() {
+            @Override
+            public void onScreenPopAnimationEnd() {
+                setBottomTabsStyleFromCurrentScreen();
+                EventBus.instance.post(new ScreenChangedEvent(getCurrentScreenStack().peek().getScreenParams()));
+            }
+        });
     }
 
     @Override

android/app/src/main/java/com/reactnativenavigation/layouts/SingleScreenLayout.java

 
     @Override
     public void pop(ScreenParams params) {
-        stack.pop(params.animateScreenTransitions);
-        EventBus.instance.post(new ScreenChangedEvent(stack.peek().getScreenParams()));
+        stack.pop(params.animateScreenTransitions, new ScreenStack.OnScreenPop() {
+            @Override
+            public void onScreenPopAnimationEnd() {
+                EventBus.instance.post(new ScreenChangedEvent(stack.peek().getScreenParams()));
+            }
+        });
     }
 
     @Override
     public void popToRoot(ScreenParams params) {
-        stack.popToRoot(params.animateScreenTransitions);
-        EventBus.instance.post(new ScreenChangedEvent(stack.peek().getScreenParams()));
+        stack.popToRoot(params.animateScreenTransitions, new ScreenStack.OnScreenPop() {
+            @Override
+            public void onScreenPopAnimationEnd() {
+                EventBus.instance.post(new ScreenChangedEvent(stack.peek().getScreenParams()));
+            }
+        });
     }
 
     @Override

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

             return;
         }
 
-        final Screen toRemove = stack.pop();
-        final Screen previous = stack.peek();
-
         if (keyboardVisibilityDetector.isKeyboardVisible()) {
             keyboardVisibilityDetector.setKeyboardCloseListener(new Runnable() {
                 @Override
                 public void run() {
                     keyboardVisibilityDetector.setKeyboardCloseListener(null);
-                    swapScreens(animated, toRemove, previous, onScreenPop);
+                    popInternal(animated, onScreenPop);
                 }
             });
             keyboardVisibilityDetector.closeKeyboard();
         } else {
-            swapScreens(animated, toRemove, previous, onScreenPop);
+            popInternal(animated, onScreenPop);
         }
     }
 
+    private void popInternal(final boolean animated, @Nullable final OnScreenPop onScreenPop) {
+        final Screen toRemove = stack.pop();
+        final Screen previous = stack.peek();
+        swapScreens(animated, toRemove, previous, onScreenPop);
+    }
+
     private void swapScreens(boolean animated, final Screen toRemove, Screen previous, OnScreenPop onScreenPop) {
         readdPrevious(previous);
         previous.setStyle();
         parent.addView(previous, 0);
     }
 
-    public void popToRoot(boolean animated) {
+    public void popToRoot(final boolean animated, @Nullable final OnScreenPop onScreenPop) {
+        if (keyboardVisibilityDetector.isKeyboardVisible()) {
+            keyboardVisibilityDetector.setKeyboardCloseListener(new Runnable() {
+                @Override
+                public void run() {
+                    keyboardVisibilityDetector.setKeyboardCloseListener(null);
+                    popToRootInternal(animated, onScreenPop);
+                }
+            });
+            keyboardVisibilityDetector.closeKeyboard();
+        } else {
+            popToRootInternal(animated, onScreenPop);
+        }
+    }
+
+    private void popToRootInternal(final boolean animated, @Nullable final OnScreenPop onScreenPop) {
         while (canPop()) {
-            pop(animated);
+            if (stack.size() == 2) {
+                popInternal(animated, onScreenPop);
+            } else {
+                popInternal(animated, null);
+            }
         }
     }