Touch emulator: enables double tap support for pages similar to Chrome on Android.

content/browser/renderer_host/input/touch_emulator.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 "content/browser/renderer_host/input/touch_emulator.h"
 
 #include "content/browser/renderer_host/input/motion_event_web.h"
 #include "content/browser/renderer_host/input/web_input_event_util.h"
 #include "content/common/input/web_touch_event_traits.h"
 #include "content/grit/content_resources.h"
@@ skipping 29 matching lines @@
 // Time between two consecutive mouse moves, during which second mouse move
 // is not converted to touch.
 const double kMouseMoveDropIntervalSeconds = 5.f / 1000;
 
 } // namespace
 
 TouchEmulator::TouchEmulator(TouchEmulatorClient* client)
     : client_(client),
       gesture_provider_config_type_(
           ui::GestureProviderConfigType::CURRENT_PLATFORM),
+      double_tap_enabled_(true),
       emulated_stream_active_sequence_count_(0),
       native_stream_active_sequence_count_(0) {
   DCHECK(client_);
   ResetState();
 
   bool use_2x = gfx::Screen::GetNativeScreen()->
       GetPrimaryDisplay().device_scale_factor() > 1.5f;
   float cursor_scale_factor = use_2x ? 2.f : 1.f;
   cursor_size_ = InitCursorFromResource(&touch_cursor_,
       cursor_scale_factor,
@@ skipping 25 matching lines @@
   pinch_gesture_active_ = false;
 }
 
 void TouchEmulator::Enable(ui::GestureProviderConfigType config_type) {
   if (!gesture_provider_ || gesture_provider_config_type_ != config_type) {
     gesture_provider_config_type_ = config_type;
     gesture_provider_.reset(new ui::FilteredGestureProvider(
         GetEmulatorGestureProviderConfig(config_type), this));
     // TODO(dgozman): Use synthetic secondary touch to support multi-touch.
     gesture_provider_->SetMultiTouchZoomSupportEnabled(false);
-    // TODO(dgozman): Enable double tap if requested by the renderer.
-    // TODO(dgozman): Don't break double-tap-based pinch with shift handling.
-    gesture_provider_->SetDoubleTapSupportForPlatformEnabled(false);
+    gesture_provider_->SetDoubleTapSupportForPageEnabled(double_tap_enabled_);
   }
   UpdateCursor();
 }
 
 void TouchEmulator::Disable() {
   if (!enabled())
     return;
 
   CancelTouch();
   gesture_provider_.reset();
   UpdateCursor();
   ResetState();
 }
 
+void TouchEmulator::SetDoubleTapSupportForPageEnabled(bool enabled) {
+  double_tap_enabled_ = enabled;
+  if (gesture_provider_)
+    gesture_provider_->SetDoubleTapSupportForPageEnabled(enabled);
+}
+
 gfx::SizeF TouchEmulator::InitCursorFromResource(
     WebCursor* cursor, float scale, int resource_id) {
   gfx::Image& cursor_image =
       content::GetContentClient()->GetNativeImageNamed(resource_id);
   WebCursor::CursorInfo cursor_info;
   cursor_info.type = blink::WebCursorInfo::TypeCustom;
   cursor_info.image_scale_factor = scale;
   cursor_info.custom_image = cursor_image.AsBitmap();
   cursor_info.hotspot =
       gfx::Point(cursor_image.Width() / 2, cursor_image.Height() / 2);
@@ skipping 314 matching lines @@
   point.screenPosition.x = mouse_event.globalX;
   point.position.y = mouse_event.y;
   point.screenPosition.y = mouse_event.globalY;
 }
 
 bool TouchEmulator::InPinchGestureMode() const {
   return shift_pressed_;
 }
 
 }  // namespace content