Support GestureBegin and GestureEnd in ui::GestureProvider

ui/events/gesture_detection/gesture_provider.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/events/gesture_detection/gesture_provider.h"
 
 #include <cmath>
 
 #include "base/auto_reset.h"
 #include "base/debug/trace_event.h"
@@ skipping 58 matching lines @@
   GestureEventDetails tap_details(type, 1, 0);
   tap_details.set_bounding_box(
       gfx::RectF(event.GetTouchMajor(), event.GetTouchMajor()));
   return tap_details;
 }
 
 }  // namespace
 
 // GestureProvider:::Config
 
-GestureProvider::Config::Config() : disable_click_delay(false) {}
+GestureProvider::Config::Config()
+    : disable_click_delay(false), send_aura_specific_gestures(false) {}
 
 GestureProvider::Config::~Config() {}
 
 // GestureProvider::ScaleGestureListener
 
 class GestureProvider::ScaleGestureListenerImpl
     : public ScaleGestureDetector::ScaleGestureListener {
  public:
   ScaleGestureListenerImpl(const ScaleGestureDetector::Config& config,
                            GestureProvider* provider)
@@ skipping 507 matching lines @@
 };
 
 // GestureProvider
 
 GestureProvider::GestureProvider(const Config& config,
                                  GestureProviderClient* client)
     : client_(client),
       needs_show_press_event_(false),
       needs_tap_ending_event_(false),
       touch_scroll_in_progress_(false),
-      pinch_in_progress_(false) {
+      pinch_in_progress_(false),
+      send_aura_specific_gestures_(false) {
   DCHECK(client);
   InitGestureDetectors(config);
 }
 
 GestureProvider::~GestureProvider() {}
 
 bool GestureProvider::OnTouchEvent(const MotionEvent& event) {
   TRACE_EVENT1("input", "GestureProvider::OnTouchEvent",
                "action", GetMotionEventActionName(event.GetAction()));
   if (!CanHandle(event))
     return false;
 
+  if (send_aura_specific_gestures_)
+    SendGestureBeginOrEndIfNecessary(event);

[jdduke (slow), 2014/04/03 20:17:16]

But don't we want the GestureEnd to come after events that might be generated by
the ACTION_UP or ACTION_POINTER_UP?  I think you'l need to have a call before
handling and after handling.

Ideally, we'd move code that comes before into a |OnTouchEventHandlingBegin(e)|,
and that would also do the ACTION_DOWN stuff below.  Then we'd have a
|OnTouchEventHandlingEnd(e)|, doing the ACTION_UP/ACTION_CANCEL cleanup (in
addition to the begin/end sending).

[tdresser, 2014/04/03 21:14:41]

Done.

+
   const bool was_touch_scrolling_ = touch_scroll_in_progress_;
   const bool in_scale_gesture =
       scale_gesture_listener_->IsScaleGestureDetectionInProgress();
 
   if (event.GetAction() == MotionEvent::ACTION_DOWN) {
     current_down_event_ = event.Clone();
     touch_scroll_in_progress_ = false;
     needs_show_press_event_ = true;
     current_longpress_time_ = base::TimeTicks();
     SendTapCancelIfNecessary(event);
@@ skipping 59 matching lines @@
 void GestureProvider::InitGestureDetectors(const Config& config) {
   TRACE_EVENT0("input", "GestureProvider::InitGestureDetectors");
   gesture_listener_.reset(
       new GestureListenerImpl(config.gesture_detector_config,
                               config.snap_scroll_controller_config,
                               config.disable_click_delay,
                               this));
 
   scale_gesture_listener_.reset(
       new ScaleGestureListenerImpl(config.scale_gesture_detector_config, this));
+  send_aura_specific_gestures_ = config.send_aura_specific_gestures;
 }
 
 bool GestureProvider::CanHandle(const MotionEvent& event) const {
   return event.GetAction() == MotionEvent::ACTION_DOWN || current_down_event_;
 }
 
 void GestureProvider::Fling(base::TimeTicks time,
                             float x,
                             float y,
                             float velocity_x,
@@ skipping 18 matching lines @@
       ET_SCROLL_FLING_START, velocity_x, velocity_y);
   Send(CreateGesture(ET_SCROLL_FLING_START, time, x, y, fling_details));
 }
 
 void GestureProvider::Send(const GestureEventData& gesture) {
   DCHECK(!gesture.time.is_null());
   // The only valid events that should be sent without an active touch sequence
   // are SHOW_PRESS and TAP, potentially triggered by the double-tap
   // delay timing out.
   DCHECK(current_down_event_ || gesture.type == ET_GESTURE_TAP ||
-         gesture.type == ET_GESTURE_SHOW_PRESS);
+         gesture.type == ET_GESTURE_SHOW_PRESS ||
+         gesture.type == ET_GESTURE_BEGIN);
 
   switch (gesture.type) {
     case ET_GESTURE_TAP_DOWN:
       needs_tap_ending_event_ = true;
       break;
     case ET_GESTURE_TAP_UNCONFIRMED:
       needs_show_press_event_ = false;
       break;
     case ET_GESTURE_TAP:
       if (needs_show_press_event_)
@@ skipping 63 matching lines @@
 
 void GestureProvider::EndTouchScrollIfNecessary(base::TimeTicks time,
                                                 bool send_scroll_end_event) {
   if (!touch_scroll_in_progress_)
     return;
   touch_scroll_in_progress_ = false;
   if (send_scroll_end_event)
     Send(CreateGesture(ET_GESTURE_SCROLL_END, time, 0, 0));
 }
 
+void GestureProvider::SendGestureBeginOrEndIfNecessary(
+    const MotionEvent& event) {
+  switch(event.GetAction()) {

[jdduke (slow), 2014/04/03 20:17:16]

Might as well move the check for the condition here, i.e., |if
(!gesture_begin_end_enabled_) return|, and just always call this depending on
the action.

[tdresser, 2014/04/03 21:14:41]

Done.

+    case MotionEvent::ACTION_DOWN:
+    case MotionEvent::ACTION_POINTER_DOWN:
+      Send(CreateGesture(ET_GESTURE_BEGIN, event));
+      break;
+    case MotionEvent::ACTION_UP:
+    case MotionEvent::ACTION_POINTER_UP:
+    case MotionEvent::ACTION_CANCEL:
+      Send(CreateGesture(ET_GESTURE_END, event));
+      break;
+    case MotionEvent::ACTION_MOVE:
+      break;
+  }
+}
+
 }  //  namespace ui