cc/input/top_controls_manager.h

   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 #ifndef CC_INPUT_TOP_CONTROLS_MANAGER_H_
   6 #define CC_INPUT_TOP_CONTROLS_MANAGER_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "base/memory/weak_ptr.h"
  10 #include "cc/input/top_controls_state.h"
  11 #include "cc/layers/layer_impl.h"
  12 #include "ui/gfx/geometry/size.h"
  13 #include "ui/gfx/geometry/vector2d_f.h"
  14
  15 namespace base {
  16 class TimeTicks;
  17 }
  18
  19 namespace cc {
  20
  21 class KeyframedFloatAnimationCurve;
  22 class LayerTreeImpl;
  23 class TopControlsManagerClient;
  24
  25 // Manages the position of the top controls.
  26 class CC_EXPORT TopControlsManager
  27     : public base::SupportsWeakPtr<TopControlsManager> {
  28  public:
  29   enum AnimationDirection {
  30     NO_ANIMATION,
  31     SHOWING_CONTROLS,
  32     HIDING_CONTROLS
  33   };
  34
  35   static scoped_ptr<TopControlsManager> Create(
  36       TopControlsManagerClient* client,
  37       float top_controls_show_threshold,
  38       float top_controls_hide_threshold);
  39   virtual ~TopControlsManager();
  40
  41   float ControlsTopOffset() const;
  42   float ContentTopOffset() const;
  43   float TopControlsShownRatio() const;
  44   float TopControlsHeight() const;
  45
  46   KeyframedFloatAnimationCurve* animation() {
  47     return top_controls_animation_.get();
  48   }
  49   AnimationDirection animation_direction() { return animation_direction_; }
  50
  51   void UpdateTopControlsState(TopControlsState constraints,
  52                               TopControlsState current,
  53                               bool animate);
  54
  55   void ScrollBegin();
  56   gfx::Vector2dF ScrollBy(const gfx::Vector2dF& pending_delta);
  57   void ScrollEnd();
  58
  59   // The caller should ensure that |Pinch{Begin,End}| are called within
  60   // the scope of |Scroll{Begin,End}|.
  61   void PinchBegin();
  62   void PinchEnd();
  63
  64   void MainThreadHasStoppedFlinging();
  65
  66   gfx::Vector2dF Animate(base::TimeTicks monotonic_time);
  67
  68  protected:
  69   TopControlsManager(TopControlsManagerClient* client,
  70                      float top_controls_show_threshold,
  71                      float top_controls_hide_threshold);
  72
  73  private:
  74   void ResetAnimations();
  75   void SetupAnimation(AnimationDirection direction);
  76   void StartAnimationIfNecessary();
  77   bool IsAnimationCompleteAtTime(base::TimeTicks time);
  78   void ResetBaseline();
  79
  80   TopControlsManagerClient* client_;  // The client manages the lifecycle of
  81                                       // this.
  82
  83   scoped_ptr<KeyframedFloatAnimationCurve> top_controls_animation_;
  84   AnimationDirection animation_direction_;
  85   TopControlsState permitted_state_;
  86
  87   // Accumulated scroll delta since last baseline reset
  88   float accumulated_scroll_delta_;
  89
  90   // Content offset when last baseline reset occurred
  91   float baseline_content_offset_;
  92
  93   // The percent height of the visible top control such that it must be shown
  94   // when the user stops the scroll.
  95   float top_controls_show_threshold_;
  96
  97   // The percent height of the visible top control such that it must be hidden
  98   // when the user stops the scroll.
  99   float top_controls_hide_threshold_;
 100
 101   bool pinch_gesture_active_;
 102
 103   DISALLOW_COPY_AND_ASSIGN(TopControlsManager);
 104 };
 105
 106 }  // namespace cc
 107
 108 #endif  // CC_INPUT_TOP_CONTROLS_MANAGER_H_