diff options
Diffstat (limited to 'content')
| -rw-r--r-- | content/public/android/java/src/org/chromium/content/browser/ContentViewGestureHandler.java | 85 |
1 files changed, 46 insertions, 39 deletions
diff --git a/content/public/android/java/src/org/chromium/content/browser/ContentViewGestureHandler.java b/content/public/android/java/src/org/chromium/content/browser/ContentViewGestureHandler.java index 32c8ad5..528fb4c 100644 --- a/content/public/android/java/src/org/chromium/content/browser/ContentViewGestureHandler.java +++ b/content/public/android/java/src/org/chromium/content/browser/ContentViewGestureHandler.java @@ -122,10 +122,14 @@ class ContentViewGestureHandler implements LongPressDelegate { // fling ends. private boolean mFlingMayBeActive; + // Used to remove the touch slop from the initial scroll event in a scroll gesture. private boolean mSeenFirstScrollEvent; private boolean mPinchInProgress = false; + // Guard against nested |trySendPendingEventsToNative()| loops. + private boolean mSendingPendingEventsToNative = false; + private static final int DOUBLE_TAP_TIMEOUT = ViewConfiguration.getDoubleTapTimeout(); //On single tap this will store the x, y coordinates of the touch. @@ -779,14 +783,7 @@ class ContentViewGestureHandler implements LongPressDelegate { endDoubleTapDragIfNecessary(null); } - if (offerTouchEventToJavaScript(event)) { - // offerTouchEventToJavaScript returns true to indicate the event was sent - // to the render process. If it is not subsequently handled, it will - // be returned via confirmTouchEvent(false) and eventually passed to - // processTouchEvent asynchronously. - return true; - } - return processTouchEvent(event); + return queueEvent(event); } finally { TraceEvent.end("onTouchEvent"); } @@ -842,8 +839,18 @@ class ContentViewGestureHandler implements LongPressDelegate { } } - private boolean offerTouchEventToJavaScript(MotionEvent event) { - if (mTouchHandlingState == NO_TOUCH_HANDLER) return false; + /** + * Queues or coalesces |event| into the pending queue. + * - If there are no touch handlers, |event| will skip the queue and be processed immediately. + * - If there are no pending events, |event| will be sent to native or processed immediately, + * depending on the disposition of the current gesture sequence. + * @return Whether the event was queued OR processed. + */ + private boolean queueEvent(MotionEvent event) { + if (mTouchHandlingState == NO_TOUCH_HANDLER) { + assert mPendingMotionEvents.isEmpty(); + return processTouchEvent(event); + } if (event.getActionMasked() == MotionEvent.ACTION_MOVE) { // Avoid flooding the renderer process with move events: if the previous pending @@ -854,7 +861,7 @@ class ContentViewGestureHandler implements LongPressDelegate { && previousEvent != mPendingMotionEvents.peekFirst() && previousEvent.getActionMasked() == MotionEvent.ACTION_MOVE && previousEvent.getPointerCount() == event.getPointerCount()) { - TraceEvent.instant("offerTouchEventToJavaScript:EventCoalesced", + TraceEvent.instant("queueEvent:EventCoalesced", "QueueSize = " + mPendingMotionEvents.size()); MotionEvent.PointerCoords[] coords = new MotionEvent.PointerCoords[event.getPointerCount()]; @@ -866,25 +873,17 @@ class ContentViewGestureHandler implements LongPressDelegate { return true; } } - if (mPendingMotionEvents.isEmpty()) { - // Add the event to the pending queue prior to calling sendPendingEventToNative. - // When sending an event to native, the callback to confirmTouchEvent can be - // synchronous or asynchronous and confirmTouchEvent expects the event to be - // in the queue when it is called. - MotionEvent clone = MotionEvent.obtain(event); - mPendingMotionEvents.add(clone); - - int forward = sendPendingEventToNative(); - if (forward != EVENT_FORWARDED_TO_NATIVE) mPendingMotionEvents.remove(clone); - return forward != EVENT_NOT_FORWARDED; + + // Copy the event, as the original may get mutated after this method returns. + MotionEvent clone = MotionEvent.obtain(event); + mPendingMotionEvents.add(clone); + if (mPendingMotionEvents.size() == 1) { + trySendPendingEventsToNative(); } else { - TraceEvent.instant("offerTouchEventToJavaScript:EventQueued", + TraceEvent.instant("queueEvent:EventQueued", "QueueSize = " + mPendingMotionEvents.size()); - // Copy the event, as the original may get mutated after this method returns. - MotionEvent clone = MotionEvent.obtain(event); - mPendingMotionEvents.add(clone); - return true; } + return true; } private int sendPendingEventToNative() { @@ -1029,19 +1028,27 @@ class ContentViewGestureHandler implements LongPressDelegate { } private void trySendPendingEventsToNative() { - while (!mPendingMotionEvents.isEmpty()) { - int forward = sendPendingEventToNative(); - if (forward == EVENT_FORWARDED_TO_NATIVE) break; - - // Even though we missed sending one event to native, as long as we haven't - // received INPUT_EVENT_ACK_STATE_NO_CONSUMER_EXISTS, we should keep sending - // events on the queue to native. - MotionEvent event = mPendingMotionEvents.removeFirst(); - if (mTouchHandlingState != JAVASCRIPT_CONSUMING_GESTURE - && forward != EVENT_DROPPED) { - processTouchEvent(event); + // Avoid nested send loops (possible when acks are synchronous), instead + // relying on the top-most call to dispatch any queued events. + if (mSendingPendingEventsToNative) return; + try { + mSendingPendingEventsToNative = true; + while (!mPendingMotionEvents.isEmpty()) { + int forward = sendPendingEventToNative(); + if (forward == EVENT_FORWARDED_TO_NATIVE) break; + + // Even though we missed sending one event to native, as long as we haven't + // received INPUT_EVENT_ACK_STATE_NO_CONSUMER_EXISTS, we should keep sending + // events on the queue to native. + MotionEvent event = mPendingMotionEvents.removeFirst(); + if (mTouchHandlingState != JAVASCRIPT_CONSUMING_GESTURE + && forward != EVENT_DROPPED) { + processTouchEvent(event); + } + recycleEvent(event); } - recycleEvent(event); + } finally { + mSendingPendingEventsToNative = false; } } |