chrome/browser/chromeos/ui/focus_ring_layer.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 CHROME_BROWSER_CHROMEOS_UI_FOCUS_RING_LAYER_H_
   6 #define CHROME_BROWSER_CHROMEOS_UI_FOCUS_RING_LAYER_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "ui/compositor/layer_delegate.h"
  11 #include "ui/gfx/rect.h"
  12
  13 namespace aura {
  14 class Window;
  15 }
  16
  17 namespace ui {
  18 class Layer;
  19 }
  20
  21 namespace chromeos {
  22
  23 // A delegate interface implemented by the object that owns a FocusRingLayer.
  24 class FocusRingLayerDelegate {
  25  public:
  26   virtual void OnDeviceScaleFactorChanged() = 0;
  27
  28  protected:
  29   virtual ~FocusRingLayerDelegate();
  30 };
  31
  32 // FocusRingLayer draws a focus ring at a given global rectangle.
  33 class FocusRingLayer : public ui::LayerDelegate {
  34  public:
  35   explicit FocusRingLayer(FocusRingLayerDelegate* delegate);
  36   virtual ~FocusRingLayer();
  37
  38   // Move the focus ring layer to the given bounds in the coordinates of
  39   // the given root window.
  40   void Set(aura::Window* root_window, const gfx::Rect& bounds);
  41
  42   ui::Layer* layer() { return layer_.get(); }
  43   aura::Window* root_window() { return root_window_; }
  44
  45  protected:
  46   // Updates |root_window_| and creates |layer_| if it doesn't exist,
  47   // or if the root window has changed. Moves the layer to the top if
  48   // it wasn't there already.
  49   void CreateOrUpdateLayer(aura::Window* root_window, const char* layer_name);
  50
  51  private:
  52   // ui::LayerDelegate overrides:
  53   virtual void OnPaintLayer(gfx::Canvas* canvas) override;
  54   virtual void OnDelegatedFrameDamage(
  55       const gfx::Rect& damage_rect_in_dip) override;
  56   virtual void OnDeviceScaleFactorChanged(float device_scale_factor) override;
  57   virtual base::Closure PrepareForLayerBoundsChange() override;
  58
  59   // The object that owns this layer.
  60   FocusRingLayerDelegate* delegate_;
  61
  62   // The current root window containing the focused object.
  63   aura::Window* root_window_;
  64
  65   // The current layer.
  66   scoped_ptr<ui::Layer> layer_;
  67
  68   // The bounding rectangle of the focused object, in |root_window_|
  69   // coordinates.
  70   gfx::Rect focus_ring_;
  71
  72   DISALLOW_COPY_AND_ASSIGN(FocusRingLayer);
  73 };
  74
  75 }  // namespace chromeos
  76
  77 #endif  // CHROME_BROWSER_CHROMEOS_UI_FOCUS_RING_LAYER_H_