cc/layers/scrollbar_layer_impl_base.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_LAYERS_SCROLLBAR_LAYER_IMPL_BASE_H_
   6 #define CC_LAYERS_SCROLLBAR_LAYER_IMPL_BASE_H_
   7
   8 #include "cc/base/cc_export.h"
   9 #include "cc/input/scrollbar.h"
  10 #include "cc/layers/layer.h"
  11 #include "cc/layers/layer_impl.h"
  12
  13 namespace cc {
  14
  15 class LayerTreeImpl;
  16
  17 class CC_EXPORT ScrollbarLayerImplBase : public LayerImpl {
  18  public:
  19   int ScrollLayerId() const {
  20     return scroll_layer_ ? scroll_layer_->id() : Layer::INVALID_ID;
  21   }
  22   int ClipLayerId() const {
  23     return clip_layer_ ? clip_layer_->id() : Layer::INVALID_ID;
  24   }
  25
  26   void SetScrollLayerAndClipLayerByIds(int scroll_layer_id, int clip_layer_id);
  27   void ClearScrollLayer() { scroll_layer_ = nullptr; }
  28   void ClearClipLayer() { clip_layer_ = nullptr; }
  29
  30   float current_pos() const { return current_pos_; }
  31   bool SetCurrentPos(float current_pos);
  32   int maximum() const { return maximum_; }
  33   bool SetMaximum(int maximum);
  34
  35   bool SetVerticalAdjust(float vertical_adjust);
  36
  37   bool is_overlay_scrollbar() const { return is_overlay_scrollbar_; }
  38   void set_is_overlay_scrollbar(bool is_overlay) {
  39     is_overlay_scrollbar_ = is_overlay;
  40   }
  41
  42   ScrollbarOrientation orientation() const { return orientation_; }
  43   bool is_left_side_vertical_scrollbar() {
  44     return is_left_side_vertical_scrollbar_;
  45   }
  46
  47   bool CanScrollOrientation() const;
  48
  49   void PushPropertiesTo(LayerImpl* layer) override;
  50   ScrollbarLayerImplBase* ToScrollbarLayer() override;
  51   void PushScrollClipPropertiesTo(LayerImpl* layer);
  52
  53   bool SetVisibleToTotalLengthRatio(float ratio);
  54   virtual gfx::Rect ComputeThumbQuadRect() const;
  55
  56   float thumb_thickness_scale_factor() {
  57     return thumb_thickness_scale_factor_;
  58   }
  59   bool SetThumbThicknessScaleFactor(float thumb_thickness_scale_factor);
  60
  61   void ScrollbarParametersDidChange(bool on_resize);
  62
  63  protected:
  64   ScrollbarLayerImplBase(LayerTreeImpl* tree_impl,
  65                          int id,
  66                          ScrollbarOrientation orientation,
  67                          bool is_left_side_vertical_scrollbar,
  68                          bool is_overlay);
  69   ~ScrollbarLayerImplBase() override;
  70
  71   gfx::Rect ScrollbarLayerRectToContentRect(const gfx::RectF& layer_rect) const;
  72
  73   float visible_to_total_length_ratio() const {
  74     return visible_to_total_length_ratio_;
  75   }
  76   float vertical_adjust() const { return vertical_adjust_; }
  77
  78   virtual int ThumbThickness() const = 0;
  79   virtual int ThumbLength() const = 0;
  80   virtual float TrackLength() const = 0;
  81   virtual int TrackStart() const = 0;
  82   // Indicates whether the thumb length can be changed without going back to the
  83   // main thread.
  84   virtual bool IsThumbResizable() const = 0;
  85
  86  private:
  87   LayerImpl* scroll_layer_;
  88   LayerImpl* clip_layer_;
  89   bool is_overlay_scrollbar_;
  90
  91   float thumb_thickness_scale_factor_;
  92   float current_pos_;
  93   int maximum_;
  94   ScrollbarOrientation orientation_;
  95   bool is_left_side_vertical_scrollbar_;
  96
  97   // Difference between the clip layer's height and the visible viewport
  98   // height (which may differ in the presence of top-controls hiding).
  99   float vertical_adjust_;
 100
 101   float visible_to_total_length_ratio_;
 102
 103   DISALLOW_COPY_AND_ASSIGN(ScrollbarLayerImplBase);
 104 };
 105
 106 }  // namespace cc
 107
 108 #endif  // CC_LAYERS_SCROLLBAR_LAYER_IMPL_BASE_H_