Refactor: Shelf Widget

ash/launcher/background_animator.h

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef ASH_LAUNCHER_BACKGROUND_ANIMATOR_H_
-#define ASH_LAUNCHER_BACKGROUND_ANIMATOR_H_
-
-#include "ash/ash_export.h"
-#include "base/basictypes.h"
-#include "ui/base/animation/animation_delegate.h"
-#include "ui/base/animation/slide_animation.h"
-
-namespace ash {
-namespace internal {
-
-// Delegate is notified any time the background changes.
-class ASH_EXPORT BackgroundAnimatorDelegate {
- public:
-  virtual void UpdateBackground(int alpha) = 0;
-
- protected:
-  virtual ~BackgroundAnimatorDelegate() {}
-};
-
-// BackgroundAnimator is used by the launcher and system tray to animate the
-// background (alpha).
-class ASH_EXPORT BackgroundAnimator : public ui::AnimationDelegate {
- public:
-  // How the background can be changed.
-  enum ChangeType {
-    CHANGE_ANIMATE,
-    CHANGE_IMMEDIATE
-  };
-
-  BackgroundAnimator(BackgroundAnimatorDelegate* delegate,
-                     int min_alpha,
-                     int max_alpha);
-  virtual ~BackgroundAnimator();
-
-  // Sets whether a background is rendered. Initial value is false. If |type|
-  // is |CHANGE_IMMEDIATE| and an animation is not in progress this notifies
-  // the delegate immediately (synchronously from this method).
-  void SetPaintsBackground(bool value, ChangeType type);
-  bool paints_background() const { return paints_background_; }
-
-  // Current alpha.
-  int alpha() const { return alpha_; }
-
-  // ui::AnimationDelegate overrides:
-  virtual void AnimationProgressed(const ui::Animation* animation) OVERRIDE;
-
- private:
-  BackgroundAnimatorDelegate* delegate_;
-
-  const int min_alpha_;
-  const int max_alpha_;
-
-  ui::SlideAnimation animation_;
-
-  // Whether the background is painted.
-  bool paints_background_;
-
-  // Current alpha value of the background.
-  int alpha_;
-
-  DISALLOW_COPY_AND_ASSIGN(BackgroundAnimator);
-};
-
-}  // namespace internal
-}  // namespace ash
-
-#endif  // ASH_LAUNCHER_BACKGROUND_ANIMATOR_H_