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 #ifndef CONTENT_BROWSER_WEB_CONTENTS_AURA_WINDOW_SLIDER_H_ 6 #define CONTENT_BROWSER_WEB_CONTENTS_AURA_WINDOW_SLIDER_H_ 7 8 #include "base/compiler_specific.h" 9 #include "base/memory/scoped_ptr.h" 10 #include "base/memory/weak_ptr.h" 11 #include "content/common/content_export.h" 12 #include "ui/aura/window_observer.h" 13 #include "ui/compositor/layer_animator.h" 14 #include "ui/events/event_handler.h" 15 16 namespace ui { 17 class Layer; 18 } 19 20 namespace content { 21 22 class ShadowLayerDelegate; 23 24 // A class for sliding the layer in a Window on top of other layers. 25 class CONTENT_EXPORT WindowSlider : public ui::EventHandler, 26 public aura::WindowObserver { 27 public: 28 class CONTENT_EXPORT Delegate { 29 public: 30 virtual ~Delegate() {} 31 32 // Creates a layer to show behind the window-layer. Called when the 33 // window-layer starts sliding out to reveal the layer underneath. 34 // The WindowSlider takes ownership of the created layer. 35 virtual ui::Layer* CreateBackLayer() = 0; 36 37 // Creates a layer to show on top of the window-layer. Called when the new 38 // layer needs to start sliding in on top of the window-layer. 39 // The WindowSlider takes ownership of the created layer. 40 virtual ui::Layer* CreateFrontLayer() = 0; 41 42 // Called when the slide is aborted. Note that when the slide is aborted, 43 // the WindowSlider resets any transform it applied on the window-layer. 44 virtual void OnWindowSlideAborted() = 0; 45 46 // Called when the slide is about to be complete. The delegate can take 47 // action with the assumption that slide will complete soon (within the 48 // duration of the final transition animation effect). 49 // This callback is always preceeded by CreateBackLayer() or by 50 // CreateFrontLayer() callback, and is guaranteed to be followed by the 51 // OnWindowSlideCompleted() callback. 52 virtual void OnWindowSlideCompleting() = 0; 53 54 // Called when the window slide completes. Note that at the end the 55 // window-layer may have been transformed. The callback here should reset 56 // the transform if necessary. |layer| is the slider's layer (previously 57 // created via CreateBackLayer() or CreateFrontLayer()). 58 virtual void OnWindowSlideCompleted(scoped_ptr<ui::Layer> layer) = 0; 59 60 // Called when the slider is destroyed. 61 virtual void OnWindowSliderDestroyed() = 0; 62 }; 63 64 // The WindowSlider slides the layers in the |owner| window. It starts 65 // intercepting scroll events on |event_window|, and uses those events to 66 // control the layer-slide. The lifetime of the slider is managed by the 67 // lifetime of |owner|, i.e. if |owner| is destroyed, then the slider also 68 // destroys itself. 69 WindowSlider(Delegate* delegate, 70 aura::Window* event_window, 71 aura::Window* owner); 72 73 virtual ~WindowSlider(); 74 75 // Changes the owner of the slider. 76 void ChangeOwner(aura::Window* new_owner); 77 78 bool IsSlideInProgress() const; 79 80 private: 81 // Sets up the slider layer correctly (sets the correct bounds of the layer, 82 // parents it to the right layer, and sets up the correct stacking order). 83 void SetupSliderLayer(); 84 85 void UpdateForScroll(float x_offset, float y_offset); 86 87 // Completes or resets the slide depending on whether the sliding layer 88 // passed the "complete slide threshold". 89 void CompleteOrResetSlide(); 90 91 // Stops all slider-owned animations, progressing them to their end-points. 92 // Note that depending on the sate of the Delegate and the WindowSlider, this 93 // may destroy the WindowSlider through animation callbacks. 94 void CompleteActiveAnimations(); 95 96 // Resets in-progress slide if any, and starts the animation of the slidden 97 // window to its original position. 98 void ResetSlide(); 99 100 // The following callbacks are triggered after an animation. 101 void SlideAnimationCompleted(scoped_ptr<ui::Layer> layer, 102 scoped_ptr<ShadowLayerDelegate> shadow); 103 104 void ResetSlideAnimationCompleted(scoped_ptr<ui::Layer> layer, 105 scoped_ptr<ShadowLayerDelegate> shadow); 106 107 // Overridden from ui::EventHandler: 108 virtual void OnKeyEvent(ui::KeyEvent* event) OVERRIDE; 109 virtual void OnMouseEvent(ui::MouseEvent* event) OVERRIDE; 110 virtual void OnScrollEvent(ui::ScrollEvent* event) OVERRIDE; 111 virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE; 112 113 // Overridden from aura::WindowObserver: 114 virtual void OnWindowRemovingFromRootWindow(aura::Window* window, 115 aura::Window* new_root) OVERRIDE; 116 117 Delegate* delegate_; 118 119 // The slider intercepts scroll events from this window. The slider does not 120 // own |event_window_|. If |event_window_| is destroyed, then the slider stops 121 // listening for events, but it doesn't destroy itself. 122 aura::Window* event_window_; 123 124 // The window the slider operates on. The lifetime of the slider is bound to 125 // this window (i.e. if |owner_| does, the slider destroys itself). The slider 126 // can also delete itself when a slide gesture is completed. This does not 127 // destroy |owner_|. 128 aura::Window* owner_; 129 130 // Set to the Animator of the currently active animation. If no animation is 131 // active, this is set to NULL. 132 ui::LayerAnimator* active_animator_; 133 134 // The accumulated amount of horizontal scroll. 135 float delta_x_; 136 137 // This keeps track of the layer created by the delegate. 138 scoped_ptr<ui::Layer> slider_; 139 140 // This manages the shadow for the layers. 141 scoped_ptr<ShadowLayerDelegate> shadow_; 142 143 float active_start_threshold_; 144 145 const float start_threshold_touchscreen_; 146 const float start_threshold_touchpad_; 147 const float complete_threshold_; 148 149 base::WeakPtrFactory<WindowSlider> weak_factory_; 150 151 DISALLOW_COPY_AND_ASSIGN(WindowSlider); 152 }; 153 154 } // namespace content 155 156 #endif // CONTENT_BROWSER_WEB_CONTENTS_AURA_WINDOW_SLIDER_H_ 157
