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 "skia/ext/refptr.h"
  10 #include "third_party/skia/include/effects/SkGradientShader.h"
  11 #include "ui/events/event.h"
  12 #include "ui/gfx/animation/animation_delegate.h"
  13 #include "ui/gfx/animation/linear_animation.h"
  14 #include "ui/gfx/canvas.h"
  15 #include "ui/gfx/geometry/size.h"
  16 #include "ui/views/widget/widget.h"
  17
  18 namespace ash {
  19
  20 const int kPointRadius = 20;
  21 const SkColor kProjectionFillColor = SkColorSetRGB(0xF5, 0xF5, 0xDC);
  22 const SkColor kProjectionStrokeColor = SK_ColorGRAY;
  23 const int kProjectionAlpha = 0xB0;
  24 const int kFadeoutDurationInMs = 250;
  25 const int kFadeoutFrameRate = 60;
  26
  27 // TouchPointView draws a single touch point. This object manages its own
  28 // lifetime and deletes itself upon fade-out completion or whenever |Remove()|
  29 // is explicitly called.
  30 class TouchPointView : public views::View,
  31                        public gfx::AnimationDelegate,
  32                        public views::WidgetObserver {
  33  public:
  34   explicit TouchPointView(views::Widget* parent_widget)
  35       : circle_center_(kPointRadius + 1, kPointRadius + 1),
  36         gradient_center_(SkPoint::Make(kPointRadius + 1,
  37                                        kPointRadius + 1)) {
  38     SetPaintToLayer(true);
  39     SetFillsBoundsOpaquely(false);
  40
  41     SetSize(gfx::Size(2 * kPointRadius + 2, 2 * kPointRadius + 2));
  42
  43     stroke_paint_.setStyle(SkPaint::kStroke_Style);
  44     stroke_paint_.setColor(kProjectionStrokeColor);
  45
  46     gradient_colors_[0] = kProjectionFillColor;
  47     gradient_colors_[1] = kProjectionStrokeColor;
  48
  49     gradient_pos_[0] = SkFloatToScalar(0.9f);
  50     gradient_pos_[1] = SkFloatToScalar(1.0f);
  51
  52     parent_widget->GetContentsView()->AddChildView(this);
  53
  54     parent_widget->AddObserver(this);
  55   }
  56
  57   void UpdateTouch(const ui::TouchEvent& touch) {
  58     if (touch.type() == ui::ET_TOUCH_RELEASED ||
  59         touch.type() == ui::ET_TOUCH_CANCELLED) {
  60       fadeout_.reset(new gfx::LinearAnimation(kFadeoutDurationInMs,
  61                                              kFadeoutFrameRate,
  62                                              this));
  63       fadeout_->Start();
  64     } else {
  65       SetX(parent()->GetMirroredXInView(touch.root_location().x()) -
  66                kPointRadius - 1);
  67       SetY(touch.root_location().y() - kPointRadius - 1);
  68     }
  69   }
  70
  71   void Remove() {
  72     delete this;
  73   }
  74
  75  private:
  76   ~TouchPointView() override {
  77     GetWidget()->RemoveObserver(this);
  78     parent()->RemoveChildView(this);
  79   }
  80
  81   // Overridden from views::View.
  82   void OnPaint(gfx::Canvas* canvas) override {
  83     int alpha = kProjectionAlpha;
  84     if (fadeout_)
  85       alpha = static_cast<int>(fadeout_->CurrentValueBetween(alpha, 0));
  86     fill_paint_.setAlpha(alpha);
  87     stroke_paint_.setAlpha(alpha);
  88     skia::RefPtr<SkShader> shader = skia::AdoptRef(
  89         SkGradientShader::CreateRadial(gradient_center_,
  90                                        SkIntToScalar(kPointRadius),
  91                                        gradient_colors_,
  92                                        gradient_pos_,
  93                                        arraysize(gradient_colors_),
  94                                        SkShader::kMirror_TileMode));
  95     fill_paint_.setShader(shader.get());
  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