From b21a9419236175a1d7f93189a7aa33e143536f9a Mon Sep 17 00:00:00 2001
From: Oleksandr Melnykov <omelnykov@fb.com>
Date: Tue, 1 Oct 2019 03:54:41 -0700
Subject: [PATCH] Fix order of method execution in Fabric ViewManager

Summary:
Because of the changes made in Fabric, the order of the execution of some methods in ViewManager has changed. In Paper the following order was guaranteed: `createViewInstance -> addEventEmitters -> updateProperties -> onAfterUpdateTransaction`. But in Fabric, the order is the following: `createViewInstance -> updateProperties -> onAfterUpdateTransaction -> addEventEmitters`. This change can actually break some existing view managers, because they rely on the fact that `addEventEmitters` will be called before `onAfterUpdateTransaction`. Check ReactVideoManager:

```
ReactModule(name = ReactVideoManager.REACT_CLASS)
public class ReactVideoManager extends SimpleViewManager<ReactVideoPlayer>
    implements VideoManagerInterface<ReactVideoPlayer> {
...

  Override
  protected void onAfterUpdateTransaction(ReactVideoPlayer view) {
    super.onAfterUpdateTransaction(view);
    view.commitChanges();
  }

 Override
  protected void addEventEmitters(
      final ThemedReactContext reactContext, final ReactVideoPlayer view) {
    view.setStateChangedListener(
        new ReactVideoPlayer.PlayerStateChangedListener() {
...
}
```

As you can see there is a state change listener registered in `addEventEmitters` and `view.commitChanges()` can actually cause a state change. It means that if `onAfterUpdateTransaction` is executed before `addEventEmitters`, the state change listener will be added after a state change has happened and the event will be missed.

Reviewed By: JoshuaGross

Differential Revision: D17600308

fbshipit-source-id: 044e09e0d64973c8237876311d37c057a1ba384e
---
 .../src/main/java/com/facebook/react/uimanager/ViewManager.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ReactAndroid/src/main/java/com/facebook/react/uimanager/ViewManager.java b/ReactAndroid/src/main/java/com/facebook/react/uimanager/ViewManager.java
index 547260dfc41..0fb5268621a 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/uimanager/ViewManager.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/uimanager/ViewManager.java
@@ -80,7 +80,6 @@ public abstract class ViewManager<T extends View, C extends ReactShadowNode>
       @Nullable StateWrapper stateWrapper,
       JSResponderHandler jsResponderHandler) {
     T view = createViewInstance(reactContext, props, stateWrapper);
-    addEventEmitters(reactContext, view);
     if (view instanceof ReactInterceptingViewGroup) {
       ((ReactInterceptingViewGroup) view).setOnInterceptTouchEventListener(jsResponderHandler);
     }
@@ -137,6 +136,7 @@ public abstract class ViewManager<T extends View, C extends ReactShadowNode>
       @Nullable ReactStylesDiffMap initialProps,
       @Nullable StateWrapper stateWrapper) {
     T view = createViewInstance(reactContext);
+    addEventEmitters(reactContext, view);
     if (initialProps != null) {
       updateProperties(view, initialProps);
     }