WebInputEventResult TouchEventManager::handleTouchEvent(
const PlatformTouchEvent& event,
const HeapVector<TouchInfo>& touchInfos)
{
// Note that the disposition of any pointer events affects only the generation of touch
// events. If all pointer events were handled (and hence no touch events were fired), that
// is still equivalent to the touch events going unhandled because pointer event handler
// don't block scroll gesture generation.
// TODO(crbug.com/507408): If PE handlers always call preventDefault, we won't see TEs until after
// scrolling starts because the scrolling would suppress upcoming PEs. This sudden "break" in TE
// suppression can make the visible TEs inconsistent (e.g. touchmove without a touchstart).
bool allTouchesReleased = true;
for (const auto& point : event.touchPoints()) {
if (point.state() != PlatformTouchPoint::TouchReleased
&& point.state() != PlatformTouchPoint::TouchCancelled)
allTouchesReleased = false;
}
// Whether a touch should be considered a "user gesture" or not is a tricky question.
// https://docs.google.com/document/d/1oF1T3O7_E4t1PYHV6gyCwHxOi3ystm0eSL5xZu7nvOg/edit#
// The touchend corresponding to a tap is always a user gesture.
bool isTap = event.touchPoints().size() == 1
&& event.touchPoints()[0].state() == PlatformTouchPoint::TouchReleased
&& !event.causesScrollingIfUncanceled();
// For now, disallow dragging as a user gesture when the events are being sent to a
// cross-origin iframe (crbug.com/582140).
bool isSameOrigin = false;
if (m_touchSequenceDocument && m_touchSequenceDocument->frame()) {
SecurityOrigin* securityOrigin = m_touchSequenceDocument->frame()->securityContext()->getSecurityOrigin();
Frame* top = m_frame->tree().top();
if (top && securityOrigin->canAccess(top->securityContext()->getSecurityOrigin()))
isSameOrigin = true;
}
OwnPtr<UserGestureIndicator> gestureIndicator;
if (isTap || isSameOrigin) {
UserGestureUtilizedCallback* callback = 0;
if (!isTap) {
// This is some other touch event that we currently consider a user gesture. So
// use a UserGestureUtilizedCallback to get metrics.
callback = &m_touchSequenceDocument->frame()->eventHandler();
}
if (m_touchSequenceUserGestureToken)
gestureIndicator = adoptPtr(new UserGestureIndicator(m_touchSequenceUserGestureToken.release(), callback));
else
gestureIndicator = adoptPtr(new UserGestureIndicator(DefinitelyProcessingUserGesture, callback));
m_touchSequenceUserGestureToken = UserGestureIndicator::currentToken();
}
return dispatchTouchEvents(event, touchInfos, allTouchesReleased);
}
bool TouchEventManager::generateTouchInfosAfterHittest(
const PlatformTouchEvent& event,
HeapVector<TouchInfo>& touchInfos)
{
bool newTouchSequence = true;
bool allTouchesReleased = true;
for (const auto& point : event.touchPoints()) {
if (point.state() != PlatformTouchPoint::TouchPressed)
newTouchSequence = false;
if (point.state() != PlatformTouchPoint::TouchReleased && point.state() != PlatformTouchPoint::TouchCancelled)
allTouchesReleased = false;
}
if (newTouchSequence) {
// Ideally we'd ASSERT(!m_touchSequenceDocument) here since we should
// have cleared the active document when we saw the last release. But we
// have some tests that violate this, ClusterFuzz could trigger it, and
// there may be cases where the browser doesn't reliably release all
// touches. http://crbug.com/345372 tracks this.
m_touchSequenceDocument.clear();
m_touchSequenceUserGestureToken.clear();
}
ASSERT(m_frame->view());
if (m_touchSequenceDocument && (!m_touchSequenceDocument->frame() || !m_touchSequenceDocument->frame()->view())) {
// If the active touch document has no frame or view, it's probably being destroyed
// so we can't dispatch events.
return false;
}
for (const auto& point : event.touchPoints()) {
TouchEventManager::TouchInfo touchInfo;
touchInfo.point = point;
touchInfos.append(touchInfo);
}
updateTargetAndRegionMapsForTouchStarts(touchInfos);
m_touchPressed = !allTouchesReleased;
// If there's no document receiving touch events, or no handlers on the
// document set to receive the events, then we can skip all the rest of
// this work.
if (!m_touchSequenceDocument || !m_touchSequenceDocument->frameHost() || !hasTouchHandlers(m_touchSequenceDocument->frameHost()->eventHandlerRegistry()) || !m_touchSequenceDocument->frame()) {
if (allTouchesReleased) {
m_touchSequenceDocument.clear();
m_touchSequenceUserGestureToken.clear();
}
return false;
}
setAllPropertiesOfTouchInfos(touchInfos);
return true;
}
PlatformGestureRecognizer::PassGestures GestureRecognizerChromium::processTouchEventForGestures(const PlatformTouchEvent& event, bool defaultPrevented)
{
m_ctrlKey = event.ctrlKey();
m_altKey = event.altKey();
m_shiftKey = event.shiftKey();
m_metaKey = event.metaKey();
OwnPtr<Vector<PlatformGestureEvent> > gestures = adoptPtr(new Vector<PlatformGestureEvent>());
const Vector<PlatformTouchPoint>& points = event.touchPoints();
for (unsigned i = 0; i < points.size(); i++) {
const PlatformTouchPoint& p = points[i];
updateValues(event.timestamp(), p);
if (GestureTransitionFunction ef = m_edgeFunctions.get(signature(m_state, p.id(), p.state(), defaultPrevented)))
((*this).*ef)(p, gestures.get());
}
return gestures.release();
}