ash/touch/touch_hud_projection.cc

   1 // Copyright 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 "ash/touch/touch_hud_projection.h"
   6
   7 #include "ash/root_window_controller.h"
   8 #include "ash/shell.h"
   9 #include "third_party/skia/include/effects/SkGradientShader.h"
  10 #include "ui/events/event.h"
  11 #include "ui/gfx/animation/animation_delegate.h"
  12 #include "ui/gfx/animation/linear_animation.h"
  13 #include "ui/gfx/canvas.h"
  14 #include "ui/gfx/size.h"
  15 #include "ui/views/widget/widget.h"
  16
  17 namespace ash {
  18
  19 const int kPointRadius = 20;
  20 const SkColor kProjectionFillColor = SkColorSetRGB(0xF5, 0xF5, 0xDC);
  21 const SkColor kProjectionStrokeColor = SK_ColorGRAY;
  22 const int kProjectionAlpha = 0xB0;
  23 const int kFadeoutDurationInMs = 250;
  24 const int kFadeoutFrameRate = 60;
  25
  26 // TouchPointView draws a single touch point. This object manages its own
  27 // lifetime and deletes itself upon fade-out completion or whenever |Remove()|
  28 // is explicitly called.
  29 class TouchPointView : public views::View,
  30                        public gfx::AnimationDelegate,
  31                        public views::WidgetObserver {
  32  public:
  33   explicit TouchPointView(views::Widget* parent_widget)
  34       : circle_center_(kPointRadius + 1, kPointRadius + 1),
  35         gradient_center_(SkPoint::Make(kPointRadius + 1,
  36                                        kPointRadius + 1)) {
  37     SetPaintToLayer(true);
  38     SetFillsBoundsOpaquely(false);
  39
  40     SetSize(gfx::Size(2 * kPointRadius + 2, 2 * kPointRadius + 2));
  41
  42     stroke_paint_.setStyle(SkPaint::kStroke_Style);
  43     stroke_paint_.setColor(kProjectionStrokeColor);
  44
  45     gradient_colors_[0] = kProjectionFillColor;
  46     gradient_colors_[1] = kProjectionStrokeColor;
  47
  48     gradient_pos_[0] = SkFloatToScalar(0.9f);
  49     gradient_pos_[1] = SkFloatToScalar(1.0f);
  50
  51     parent_widget->GetContentsView()->AddChildView(this);
  52
  53     parent_widget->AddObserver(this);
  54   }
  55
  56   void UpdateTouch(const ui::TouchEvent& touch) {
  57     if (touch.type() == ui::ET_TOUCH_RELEASED ||
  58         touch.type() == ui::ET_TOUCH_CANCELLED) {
  59       fadeout_.reset(new gfx::LinearAnimation(kFadeoutDurationInMs,
  60                                              kFadeoutFrameRate,
  61                                              this));
  62       fadeout_->Start();
  63     } else {
  64       SetX(parent()->GetMirroredXInView(touch.root_location().x()) -
  65                kPointRadius - 1);
  66       SetY(touch.root_location().y() - kPointRadius - 1);
  67     }
  68   }
  69
  70   void Remove() {
  71     delete this;
  72   }
  73
  74  private:
  75   ~TouchPointView() override {
  76     GetWidget()->RemoveObserver(this);
  77     parent()->RemoveChildView(this);
  78   }
  79
  80   // Overridden from views::View.
  81   void OnPaint(gfx::Canvas* canvas) override {
  82     int alpha = kProjectionAlpha;
  83     if (fadeout_)
  84       alpha = static_cast<int>(fadeout_->CurrentValueBetween(alpha, 0));
  85     fill_paint_.setAlpha(alpha);
  86     stroke_paint_.setAlpha(alpha);
  87     SkShader* shader = SkGradientShader::CreateRadial(
  88         gradient_center_,
  89         SkIntToScalar(kPointRadius),
  90         gradient_colors_,
  91         gradient_pos_,
  92         arraysize(gradient_colors_),
  93         SkShader::kMirror_TileMode);
  94     fill_paint_.setShader(shader);
  95     shader->unref();
  96     canvas->DrawCircle(circle_center_, SkIntToScalar(kPointRadius),
  97                        fill_paint_);
  98     canvas->DrawCircle(circle_center_, SkIntToScalar(kPointRadius),
  99                        stroke_paint_);
 100   }
 101
 102   // Overridden from gfx::AnimationDelegate.
 103   void AnimationEnded(const gfx::Animation* animation) override {
 104     DCHECK_EQ(fadeout_.get(), animation);
 105     delete this;
 106   }
 107
 108   void AnimationProgressed(const gfx::Animation* animation) override {
 109     DCHECK_EQ(fadeout_.get(), animation);
 110     SchedulePaint();
 111   }
 112
 113   void AnimationCanceled(const gfx::Animation* animation) override {
 114     AnimationEnded(animation);
 115   }
 116
 117   // Overridden from views::WidgetObserver.
 118   void OnWidgetDestroying(views::Widget* widget) override {
 119     if (fadeout_)
 120       fadeout_->Stop();
 121     else
 122       Remove();
 123   }
 124
 125   const gfx::Point circle_center_;
 126   const SkPoint gradient_center_;
 127
 128   SkPaint fill_paint_;
 129   SkPaint stroke_paint_;
 130   SkColor gradient_colors_[2];
 131   SkScalar gradient_pos_[2];
 132
 133   scoped_ptr<gfx::Animation> fadeout_;
 134
 135   DISALLOW_COPY_AND_ASSIGN(TouchPointView);
 136 };
 137
 138 TouchHudProjection::TouchHudProjection(aura::Window* initial_root)
 139     : TouchObserverHUD(initial_root) {
 140 }
 141
 142 TouchHudProjection::~TouchHudProjection() {
 143 }
 144
 145 void TouchHudProjection::Clear() {
 146   for (std::map<int, TouchPointView*>::iterator iter = points_.begin();
 147       iter != points_.end(); iter++)
 148     iter->second->Remove();
 149   points_.clear();
 150 }
 151
 152 void TouchHudProjection::OnTouchEvent(ui::TouchEvent* event) {
 153   if (event->type() == ui::ET_TOUCH_PRESSED) {
 154     TouchPointView* point = new TouchPointView(widget());
 155     point->UpdateTouch(*event);
 156     std::pair<std::map<int, TouchPointView*>::iterator, bool> result =
 157         points_.insert(std::make_pair(event->touch_id(), point));
 158     // If a |TouchPointView| is already mapped to the touch id, remove it and
 159     // replace it with the new one.
 160     if (!result.second) {
 161       result.first->second->Remove();
 162       result.first->second = point;
 163     }
 164   } else {
 165     std::map<int, TouchPointView*>::iterator iter =
 166         points_.find(event->touch_id());
 167     if (iter != points_.end()) {
 168       iter->second->UpdateTouch(*event);
 169       if (event->type() == ui::ET_TOUCH_RELEASED ||
 170           event->type() == ui::ET_TOUCH_CANCELLED)
 171         points_.erase(iter);
 172     }
 173   }
 174 }
 175
 176 void TouchHudProjection::SetHudForRootWindowController(
 177     RootWindowController* controller) {
 178   controller->set_touch_hud_projection(this);
 179 }
 180
 181 void TouchHudProjection::UnsetHudForRootWindowController(
 182     RootWindowController* controller) {
 183   controller->set_touch_hud_projection(NULL);
 184 }
 185
 186 }  // namespace ash