ash/sticky_keys/sticky_keys_overlay.h

   1 // Copyright 2014 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 ASH_STICKY_KEYS_STICKY_KEYS_OVERLAY_H_
   6 #define ASH_STICKY_KEYS_STICKY_KEYS_OVERLAY_H_
   7
   8 #include "ash/ash_export.h"
   9 #include "ash/sticky_keys/sticky_keys_state.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "ui/compositor/layer_animation_observer.h"
  12 #include "ui/events/event_constants.h"
  13 #include "ui/gfx/geometry/size.h"
  14
  15 namespace gfx {
  16 class Rect;
  17 }
  18
  19 namespace views {
  20 class Widget;
  21 }
  22
  23 namespace ash {
  24
  25 class StickyKeysOverlayView;
  26
  27 // Controls the overlay UI for sticky keys, an accessibility feature allowing
  28 // use of modifier keys without holding them down. This overlay will appear as
  29 // a transparent window on the top left of the screen, showing the state of
  30 // each sticky key modifier.
  31 class ASH_EXPORT StickyKeysOverlay : public ui::LayerAnimationObserver {
  32  public:
  33   StickyKeysOverlay();
  34   virtual ~StickyKeysOverlay();
  35
  36   // Shows or hides the overlay.
  37   void Show(bool visible);
  38
  39   // Updates the overlay with the current state of a sticky key modifier.
  40   void SetModifierKeyState(ui::EventFlags modifier,
  41                            StickyKeyState state);
  42
  43   // Get the current state of the sticky key modifier in the overlay.
  44   StickyKeyState GetModifierKeyState(ui::EventFlags modifier);
  45
  46   // Returns true if the overlay is currently visible. If the overlay is
  47   // animating, the returned value is the target of the animation.
  48   bool is_visible() { return is_visible_; }
  49
  50  private:
  51   // Returns the current bounds of the overlay, which is based on visibility.
  52   gfx::Rect CalculateOverlayBounds();
  53
  54   // gfx::LayerAnimationObserver overrides:
  55   virtual void OnLayerAnimationEnded(
  56       ui::LayerAnimationSequence* sequence) OVERRIDE;
  57   virtual void OnLayerAnimationAborted(
  58       ui::LayerAnimationSequence* sequence) OVERRIDE;
  59   virtual void OnLayerAnimationScheduled(
  60       ui::LayerAnimationSequence* sequence) OVERRIDE;
  61
  62   bool is_visible_;
  63   scoped_ptr<views::Widget> overlay_widget_;
  64   // Ownership of |overlay_view_| is passed to the view heirarchy.
  65   StickyKeysOverlayView* overlay_view_;
  66   gfx::Size widget_size_;
  67 };
  68
  69 }  // namespace ash
  70
  71 #endif  // ASH_STICKY_KEYS_STICKY_KEYS_OVERLAY_H_