| // 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 UI_VIEWS_ANIMATION_SCROLL_ANIMATOR_H_ |
| #define UI_VIEWS_ANIMATION_SCROLL_ANIMATOR_H_ |
| |
| #include "base/basictypes.h" |
| #include "base/memory/scoped_ptr.h" |
| #include "ui/gfx/animation/animation_delegate.h" |
| #include "ui/views/views_export.h" |
| |
| namespace gfx { |
| class SlideAnimation; |
| } |
| |
| namespace views { |
| |
| class VIEWS_EXPORT ScrollDelegate { |
| public: |
| // Returns true if the content was actually scrolled, false otherwise. |
| virtual bool OnScroll(float dx, float dy) = 0; |
| |
| protected: |
| ~ScrollDelegate() {} |
| }; |
| |
| class VIEWS_EXPORT ScrollAnimator : public gfx::AnimationDelegate { |
| public: |
| // The ScrollAnimator does not own the delegate. Uses default acceleration. |
| explicit ScrollAnimator(ScrollDelegate* delegate); |
| ~ScrollAnimator() override; |
| |
| // Use this if you would prefer different acceleration than the default. |
| void set_acceleration(float acceleration) { acceleration_ = acceleration; } |
| |
| void Start(float velocity_x, float velocity_y); |
| void Stop(); |
| |
| bool is_scrolling() const { return !!animation_.get(); } |
| |
| private: |
| // Implementation of gfx::AnimationDelegate. |
| void AnimationEnded(const gfx::Animation* animation) override; |
| void AnimationProgressed(const gfx::Animation* animation) override; |
| void AnimationCanceled(const gfx::Animation* animation) override; |
| |
| ScrollDelegate* delegate_; |
| |
| float velocity_x_; |
| float velocity_y_; |
| float last_t_; |
| float duration_; |
| float acceleration_; |
| |
| scoped_ptr<gfx::SlideAnimation> animation_; |
| |
| DISALLOW_COPY_AND_ASSIGN(ScrollAnimator); |
| }; |
| |
| } // namespace views |
| |
| #endif // UI_VIEWS_ANIMATION_SCROLL_ANIMATOR_H_ |