1 /*
2  * Copyright (c) 2021 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef FOUNDATION_ACE_FRAMEWORKS_CORE_COMPONENTS_SCROLL_SCROLL_FADE_EFFECT_H
17 #define FOUNDATION_ACE_FRAMEWORKS_CORE_COMPONENTS_SCROLL_SCROLL_FADE_EFFECT_H
18 
19 #include "base/utils/macros.h"
20 #include "core/components/scroll/scroll_edge_effect.h"
21 #include "core/components/scroll/scroll_fade_controller.h"
22 #include "core/components/scroll/scroll_fade_painter.h"
23 
24 namespace OHOS::Ace {
25 
26 class ACE_EXPORT ScrollFadeEffect final : public ScrollEdgeEffect {
27     DECLARE_ACE_TYPE(ScrollFadeEffect, ScrollEdgeEffect);
28 
29 public:
30     explicit ScrollFadeEffect(const Color& color = Color::GRAY)
31         : ScrollEdgeEffect(EdgeEffect::FADE), fadeColor_(color) {}
32     ~ScrollFadeEffect() override = default;
33 
GetFadeColor()34     const Color& GetFadeColor() const
35     {
36         return fadeColor_;
37     }
38 
39     void InitialEdgeEffect() override;
40     double CalculateOverScroll(double oldPosition, bool isReachMax) override;
41     void Paint(RenderContext& context, const Size& viewPort, const Offset& offset) override;
42     void HandleOverScroll(Axis axis, double overScroll, const Size& viewPort) override;
43 
44 private:
45     void ResetFadeEffect(const Color& color);
46     void SetOpacityAndScale(double opacity, double scale);
47     void SetPaintDirection(Axis axis, double overScroll);
48 
49     Color fadeColor_ = Color::GRAY;
50     RefPtr<ScrollFadePainter> fadePainter_;
51     RefPtr<ScrollFadeController> fadeController_;
52 };
53 
54 } // namespace OHOS::Ace
55 
56 #endif // FOUNDATION_ACE_FRAMEWORKS_CORE_COMPONENTS_SCROLL_SCROLL_FADE_EFFECT_H
57