content/browser/web_contents/aura/overscroll_window_delegate.cc

   1 // Copyright 2015 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/web_contents/aura/overscroll_window_delegate.h"
   6
   7 #include "base/i18n/rtl.h"
   8 #include "content/browser/frame_host/navigation_controller_impl.h"
   9 #include "content/browser/frame_host/navigation_entry_impl.h"
  10 #include "content/browser/renderer_host/overscroll_controller_delegate.h"
  11 #include "content/public/browser/overscroll_configuration.h"
  12 #include "ui/aura/window.h"
  13 #include "ui/events/event.h"
  14 #include "ui/gfx/image/image_png_rep.h"
  15
  16 namespace content {
  17
  18 OverscrollWindowDelegate::OverscrollWindowDelegate(
  19     OverscrollControllerDelegate* delegate,
  20     const gfx::Image& image)
  21     : delegate_(delegate),
  22       overscroll_mode_(OVERSCROLL_NONE),
  23       delta_x_(0.f),
  24       complete_threshold_ratio_(content::GetOverscrollConfig(
  25           content::OVERSCROLL_CONFIG_HORIZ_THRESHOLD_COMPLETE)),
  26       start_threshold_touchscreen_(content::GetOverscrollConfig(
  27           content::OVERSCROLL_CONFIG_HORIZ_THRESHOLD_START_TOUCHSCREEN)),
  28       start_threshold_touchpad_(content::GetOverscrollConfig(
  29           content::OVERSCROLL_CONFIG_HORIZ_THRESHOLD_START_TOUCHPAD)),
  30       active_start_threshold_(0.f) {
  31   SetImage(image);
  32 }
  33
  34 OverscrollWindowDelegate::~OverscrollWindowDelegate() {
  35 }
  36
  37 void OverscrollWindowDelegate::StartOverscroll() {
  38   OverscrollMode old_mode = overscroll_mode_;
  39   if (delta_x_ > 0)
  40     overscroll_mode_ = OVERSCROLL_EAST;
  41   else
  42     overscroll_mode_ = OVERSCROLL_WEST;
  43   delegate_->OnOverscrollModeChange(old_mode, overscroll_mode_);
  44 }
  45
  46 void OverscrollWindowDelegate::ResetOverscroll() {
  47   if (overscroll_mode_ == OVERSCROLL_NONE)
  48     return;
  49   delegate_->OnOverscrollModeChange(overscroll_mode_, OVERSCROLL_NONE);
  50   overscroll_mode_ = OVERSCROLL_NONE;
  51   delta_x_ = 0;
  52 }
  53
  54 void OverscrollWindowDelegate::CompleteOrResetOverscroll() {
  55   if (overscroll_mode_ == OVERSCROLL_NONE)
  56     return;
  57   int width = delegate_->GetVisibleBounds().width();
  58   float ratio = (fabs(delta_x_)) / width;
  59   if (ratio < complete_threshold_ratio_) {
  60     ResetOverscroll();
  61     return;
  62   }
  63   delegate_->OnOverscrollComplete(overscroll_mode_);
  64   overscroll_mode_ = OVERSCROLL_NONE;
  65   delta_x_ = 0;
  66 }
  67
  68 void OverscrollWindowDelegate::UpdateOverscroll(float delta_x) {
  69   float old_delta_x = delta_x_;
  70   delta_x_ += delta_x;
  71   if (overscroll_mode_ == OVERSCROLL_NONE) {
  72     if (fabs(delta_x_) > active_start_threshold_)
  73       StartOverscroll();
  74     return;
  75   }
  76   if ((old_delta_x < 0 && delta_x_ > 0) || (old_delta_x > 0 && delta_x_ < 0)) {
  77     ResetOverscroll();
  78     return;
  79   }
  80   delegate_->OnOverscrollUpdate(delta_x_, 0.f);
  81 }
  82
  83 void OverscrollWindowDelegate::OnKeyEvent(ui::KeyEvent* event) {
  84   ResetOverscroll();
  85 }
  86
  87 void OverscrollWindowDelegate::OnMouseEvent(ui::MouseEvent* event) {
  88   if (!(event->flags() & ui::EF_IS_SYNTHESIZED) &&
  89       event->type() != ui::ET_MOUSE_CAPTURE_CHANGED) {
  90     ResetOverscroll();
  91   }
  92 }
  93
  94 void OverscrollWindowDelegate::OnScrollEvent(ui::ScrollEvent* event) {
  95   active_start_threshold_ = start_threshold_touchpad_;
  96   if (event->type() == ui::ET_SCROLL)
  97     UpdateOverscroll(event->x_offset_ordinal());
  98   else if (event->type() == ui::ET_SCROLL_FLING_START)
  99     CompleteOrResetOverscroll();
 100   else
 101     ResetOverscroll();
 102   event->SetHandled();
 103 }
 104
 105 void OverscrollWindowDelegate::OnGestureEvent(ui::GestureEvent* event) {
 106   active_start_threshold_ = start_threshold_touchscreen_;
 107   switch (event->type()) {
 108     case ui::ET_GESTURE_SCROLL_UPDATE:
 109       UpdateOverscroll(event->details().scroll_x());
 110       break;
 111
 112     case ui::ET_GESTURE_SCROLL_END:
 113       CompleteOrResetOverscroll();
 114       break;
 115
 116     case ui::ET_SCROLL_FLING_START:
 117       CompleteOrResetOverscroll();
 118       break;
 119
 120     case ui::ET_GESTURE_PINCH_BEGIN:
 121     case ui::ET_GESTURE_PINCH_UPDATE:
 122     case ui::ET_GESTURE_PINCH_END:
 123       ResetOverscroll();
 124       break;
 125
 126     default:
 127       break;
 128   }
 129   event->SetHandled();
 130 }
 131
 132 }  // namespace content