Dispatch native handled events to JS

Summary: When native events where handled they were not sent to JS as an optimization but this caused some issues. One of the major one is touches are not handled properly inside a ScrollView with an Animated.event because it doesn't receive scroll events so it can't cancel the touch if the user scrolled. Closes #10981 Differential Revision: D4226403 Pulled By: astreet fbshipit-source-id: 41278d3ed4b684af142d9e273b11b974eb679879
facebook · Nov 23, 2016 · b49e7af · b49e7af
1 parent dad5204
commit b49e7af
Show file tree

Hide file tree

Showing 6 changed files with 9 additions and 33 deletions.
diff --git a/Libraries/NativeAnimation/RCTNativeAnimatedModule.m b/Libraries/NativeAnimation/RCTNativeAnimatedModule.m
@@ -322,11 +322,11 @@ - (void)animatedNode:(RCTValueAnimatedNode *)node didUpdateValue:(CGFloat)value
                      body:@{@"tag": node.nodeTag, @"value": @(value)}];
 }
 
-- (BOOL)eventDispatcherWillDispatchEvent:(id<RCTEvent>)event
+- (void)eventDispatcherWillDispatchEvent:(id<RCTEvent>)event
 {
   // Native animated events only work for events dispatched from the main queue.
   if (!RCTIsMainQueue() || _eventAnimationDrivers.count == 0) {
-    return NO;
+    return;
   }
 
   NSString *key = [NSString stringWithFormat:@"%@%@", event.viewTag, event.eventName];
@@ -336,11 +336,7 @@ - (BOOL)eventDispatcherWillDispatchEvent:(id<RCTEvent>)event
     [driver updateWithEvent:event];
     [self updateViewsProps];
     [driver.valueNode cleanupAnimationUpdate];
-
-    return YES;
   }
-
-  return NO;
 }
 
 - (void)updateViewsProps

diff --git a/React/Base/RCTEventDispatcher.h b/React/Base/RCTEventDispatcher.h
@@ -58,10 +58,9 @@ RCT_EXTERN NSString *RCTNormalizeInputEventName(NSString *eventName);
 
 /**
  * Called before dispatching an event, on the same thread the event was
- * dispatched from. Return YES if the event was handled and must not be
- * sent to JS.
+ * dispatched from.
  */
-- (BOOL)eventDispatcherWillDispatchEvent:(id<RCTEvent>)event;
+- (void)eventDispatcherWillDispatchEvent:(id<RCTEvent>)event;
 
 @end
 

diff --git a/React/Base/RCTEventDispatcher.m b/React/Base/RCTEventDispatcher.m
@@ -146,19 +146,12 @@ - (void)sendEvent:(id<RCTEvent>)event
 {
   [_observersLock lock];
 
-  BOOL eventHandled = NO;
   for (id<RCTEventDispatcherObserver> observer in _observers) {
-    if ([observer eventDispatcherWillDispatchEvent:event]) {
-      eventHandled = YES;
-    }
+    [observer eventDispatcherWillDispatchEvent:event];
   }
 
   [_observersLock unlock];
 
-  if (eventHandled) {
-    return;
-  }
-
   [_eventQueueLock lock];
 
   NSNumber *eventID = RCTGetEventID(event);

diff --git a/ReactAndroid/src/main/java/com/facebook/react/animated/NativeAnimatedNodesManager.java b/ReactAndroid/src/main/java/com/facebook/react/animated/NativeAnimatedNodesManager.java
@@ -314,10 +314,10 @@ public void removeAnimatedEventFromView(int viewTag, String eventName) {
   }
 
   @Override
-  public boolean onEventDispatch(Event event) {
+  public void onEventDispatch(Event event) {
     // Only support events dispatched from the UI thread.
     if (!UiThreadUtil.isOnUiThread()) {
-      return false;
+      return;
     }
 
     if (!mEventDrivers.isEmpty()) {
@@ -332,11 +332,8 @@ public boolean onEventDispatch(Event event) {
       if (eventDriver != null) {
         event.dispatch(eventDriver);
         mUpdatedNodes.put(eventDriver.mValueNode.mTag, eventDriver.mValueNode);
-        return true;
       }
     }
-
-    return false;
   }
 
   /**

diff --git a/ReactAndroid/src/main/java/com/facebook/react/uimanager/events/EventDispatcher.java b/ReactAndroid/src/main/java/com/facebook/react/uimanager/events/EventDispatcher.java
@@ -114,16 +114,8 @@ public EventDispatcher(ReactApplicationContext reactContext) {
   public void dispatchEvent(Event event) {
     Assertions.assertCondition(event.isInitialized(), "Dispatched event hasn't been initialized");
 
-    boolean eventHandled = false;
     for (EventDispatcherListener listener : mListeners) {
-      if (listener.onEventDispatch(event)) {
-        eventHandled = true;
-      }
-    }
-
-    // If the event was handled by one of the event listener don't send it to JS.
-    if (eventHandled) {
-      return;
+      listener.onEventDispatch(event);
     }
 
     synchronized (mEventsStagingLock) {

diff --git a/ReactAndroid/src/main/java/com/facebook/react/uimanager/events/EventDispatcherListener.java b/ReactAndroid/src/main/java/com/facebook/react/uimanager/events/EventDispatcherListener.java
@@ -10,7 +10,6 @@ public interface EventDispatcherListener {
    * Called on every time an event is dispatched using {#link EventDispatcher#dispatchEvent}. Will be
    * called from the same thread that the event is being dispatched from.
    * @param event Event that was dispatched
-   * @return If the event was handled. If true the event won't be sent to JS.
    */
-  boolean onEventDispatch(Event event);
+  void onEventDispatch(Event event);
 }