| // 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_ANDROID_OVERSCROLL_GLOW_H_ |
| #define UI_ANDROID_OVERSCROLL_GLOW_H_ |
| |
| #include <memory> |
| |
| #include "base/macros.h" |
| #include "base/memory/ref_counted.h" |
| #include "base/time/time.h" |
| #include "ui/android/edge_effect_base.h" |
| #include "ui/android/ui_android_export.h" |
| #include "ui/gfx/geometry/size_f.h" |
| #include "ui/gfx/geometry/vector2d_f.h" |
| |
| namespace cc { |
| class Layer; |
| } |
| |
| namespace ui { |
| |
| // Provides lazy, customized EdgeEffect creation. |
| class UI_ANDROID_EXPORT OverscrollGlowClient { |
| public: |
| virtual ~OverscrollGlowClient() {} |
| |
| // Called lazily, after the initial overscrolling event. |
| virtual std::unique_ptr<EdgeEffectBase> CreateEdgeEffect() = 0; |
| }; |
| |
| /* |OverscrollGlow| mirrors its Android counterpart, OverscrollGlow.java. |
| * Conscious tradeoffs were made to align this as closely as possible with the |
| * original Android Java version. |
| */ |
| class UI_ANDROID_EXPORT OverscrollGlow { |
| public: |
| // |client| must be valid for the duration of the effect's lifetime. |
| // The effect is enabled by default, but will remain dormant until the first |
| // overscroll event. |
| explicit OverscrollGlow(OverscrollGlowClient* client); |
| virtual ~OverscrollGlow(); |
| |
| // Called when the root content layer overscrolls. |
| // |accumulated_overscroll| and |overscroll_delta| are in device pixels, while |
| // |velocity| is in device pixels / second. |
| // |overscroll_location| is the coordinate of the causal overscrolling event. |
| // Returns true if the effect still needs animation ticks. |
| // This method is made virtual for mocking. |
| virtual bool OnOverscrolled(base::TimeTicks current_time, |
| gfx::Vector2dF accumulated_overscroll, |
| gfx::Vector2dF overscroll_delta, |
| gfx::Vector2dF velocity, |
| gfx::Vector2dF overscroll_location); |
| |
| // Returns true if the effect still needs animation ticks, with effect layers |
| // attached to |parent_layer| if necessary. |
| // Note: The effect will detach itself when no further animation is required. |
| bool Animate(base::TimeTicks current_time, cc::Layer* parent_layer); |
| |
| // Update the effect according to the most recent display parameters, |
| // Note: All dimensions are in device pixels. |
| void OnFrameUpdated(const gfx::SizeF& viewport_size, |
| const gfx::SizeF& content_size, |
| const gfx::Vector2dF& content_scroll_offset); |
| |
| // Reset the effect to its inactive state, clearing any active effects. |
| void Reset(); |
| |
| // Whether the effect is active, either being pulled or receding. |
| bool IsActive() const; |
| |
| // The maximum alpha value (in the range [0,1]) of any animated edge layers. |
| // If the effect is inactive, this will be 0. |
| float GetVisibleAlpha() const; |
| |
| private: |
| enum Axis { AXIS_X, AXIS_Y }; |
| enum { EDGE_COUNT = EdgeEffectBase::EDGE_COUNT }; |
| |
| // Returns whether the effect has been properly initialized. |
| bool InitializeIfNecessary(); |
| bool CheckNeedsAnimate(); |
| void UpdateLayerAttachment(cc::Layer* parent); |
| void Detach(); |
| void Pull(base::TimeTicks current_time, |
| const gfx::Vector2dF& overscroll_delta, |
| const gfx::Vector2dF& overscroll_location); |
| void Absorb(base::TimeTicks current_time, |
| const gfx::Vector2dF& velocity, |
| bool x_overscroll_started, |
| bool y_overscroll_started); |
| void Release(base::TimeTicks current_time); |
| |
| EdgeEffectBase* GetOppositeEdge(int edge_index); |
| |
| OverscrollGlowClient* const client_; |
| std::unique_ptr<EdgeEffectBase> edge_effects_[EDGE_COUNT]; |
| |
| gfx::SizeF viewport_size_; |
| float edge_offsets_[EDGE_COUNT]; |
| bool initialized_; |
| bool allow_horizontal_overscroll_; |
| bool allow_vertical_overscroll_; |
| |
| scoped_refptr<cc::Layer> root_layer_; |
| |
| DISALLOW_COPY_AND_ASSIGN(OverscrollGlow); |
| }; |
| |
| } // namespace ui |
| |
| #endif // UI_ANDROID_OVERSCROLL_GLOW_H_ |