src/content/browser/renderer_host/touch_smooth_scroll_gesture_aura.cc

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/browser/renderer_host/touch_smooth_scroll_gesture_aura.h"
   6
   7 #include "content/browser/renderer_host/render_widget_host_impl.h"
   8 #include "ui/aura/root_window.h"
   9 #include "ui/events/event.h"
  10 #include "ui/events/event_utils.h"
  11 #include "ui/gfx/transform.h"
  12
  13 namespace {
  14
  15 void InjectTouchEvent(const gfx::Point& location,
  16                       ui::EventType type,
  17                       aura::Window* window) {
  18   gfx::Point screen_location = location;
  19   aura::Window* root_window = window->GetRootWindow();
  20   // First convert the location from Window to RootWindow.
  21   aura::Window::ConvertPointToTarget(window, root_window, &screen_location);
  22   // Then convert the location from RootWindow to screen.
  23   aura::WindowEventDispatcher* dispatcher = root_window->GetDispatcher();
  24   dispatcher->ConvertPointToHost(&screen_location);
  25   ui::TouchEvent touch(type, screen_location, 0, 0, ui::EventTimeForNow(),
  26                        1.0f, 1.0f, 1.0f, 1.0f);
  27   dispatcher->AsRootWindowHostDelegate()->OnHostTouchEvent(&touch);
  28 }
  29
  30 }  // namespace
  31
  32 namespace content {
  33
  34 TouchSmoothScrollGestureAura::TouchSmoothScrollGestureAura(bool scroll_down,
  35                                                            int pixels_to_scroll,
  36                                                            int mouse_event_x,
  37                                                            int mouse_event_y,
  38                                                            aura::Window* window)
  39     : scroll_down_(scroll_down),
  40       pixels_to_scroll_(pixels_to_scroll),
  41       pixels_scrolled_(0),
  42       location_(mouse_event_x, mouse_event_y),
  43       window_(window) {
  44 }
  45
  46 TouchSmoothScrollGestureAura::~TouchSmoothScrollGestureAura() {}
  47
  48 bool TouchSmoothScrollGestureAura::ForwardInputEvents(
  49     base::TimeTicks now,
  50     RenderWidgetHost* host) {
  51   if (pixels_scrolled_ >= pixels_to_scroll_)
  52     return false;
  53
  54   RenderWidgetHostImpl* host_impl = RenderWidgetHostImpl::From(host);
  55   float position_delta = synthetic_gesture_calculator_.GetDelta(now,
  56       host_impl->GetSyntheticGestureMessageInterval());
  57
  58   if (pixels_scrolled_ == 0) {
  59     InjectTouchEvent(location_, ui::ET_TOUCH_PRESSED, window_);
  60   }
  61
  62   location_.Offset(0, scroll_down_ ? -position_delta : position_delta);
  63     InjectTouchEvent(location_, ui::ET_TOUCH_MOVED, window_);
  64
  65   pixels_scrolled_ += abs(position_delta);
  66
  67   if (pixels_scrolled_ >= pixels_to_scroll_) {
  68     InjectTouchEvent(location_, ui::ET_TOUCH_RELEASED, window_);
  69   }
  70
  71   return true;
  72 }
  73
  74 }  // namespace content