/*
* Copyright (c) 2020-2021 Huawei Device Co., Ltd.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @addtogroup UI_Components
* @{
*
* @brief Defines UI components such as buttons, texts, images, lists, and progress bars.
*
* @since 1.0
* @version 1.0
*/
/**
* @file ui_scroll_view.h
*
* @brief Declares a view group that allows its child views to be displayed as scroll events occur.
*
* @since 1.0
* @version 1.0
*/
#ifndef GRAPHIC_LITE_UI_SCROLL_VIEW_H
#define GRAPHIC_LITE_UI_SCROLL_VIEW_H
#include "animator/animator.h"
#include "components/ui_abstract_scroll.h"
namespace OHOS {
/**
* @brief Supports horizontal or vertical scroll of child views. This class is inherited from {@link UIAbstractScroll}.
*
* Horizontal or vertical scroll occurs only when the width or height of the child view is greater than that of the
* <b>UIScrollView</b>.
*
* @since 1.0
* @version 1.0
*/
class UIScrollView : public UIAbstractScroll {
public:
/**
* @brief Represents a listener that contains a callback to be invoked upon scroll state changes. The state can
* either be {@link SCROLL_STATE_STOP} or {@link SCROLL_STATE_MOVE}.
* @since 1.0
* @version 1.0
*/
class OnScrollListener : public HeapBase {
public:
/**
* @brief A constructor used to create an <b>OnScrollListener</b> instance with the default scroll state
* {@link SCROLL_STATE_STOP}.
* @since 1.0
* @version 1.0
*/
OnScrollListener() : state_(SCROLL_STATE_STOP) {}
/**
* @brief A destructor used to delete the <b>OnScrollListener</b> instance.
* @since 1.0
* @version 1.0
*/
virtual ~OnScrollListener() {}
/**
* @brief Called when a scroll starts.
*
* @since 1.0
* @version 1.0
*/
virtual void OnScrollStart() {}
/**
* @brief Called when a scroll ends.
*
* @since 1.0
* @version 1.0
*/
virtual void OnScrollEnd() {}
/**
* @brief Obtains the scroll state of this view.
*
* @return Returns the scroll state, either {@link SCROLL_STATE_STOP} or {@link SCROLL_STATE_MOVE}.
* @since 1.0
* @version 1.0
*/
uint8_t GetScrollState() const
{
return state_;
}
void SetScrollState(uint8_t state)
{
state_ = state;
}
static constexpr uint8_t SCROLL_STATE_STOP = 0;
static constexpr uint8_t SCROLL_STATE_MOVE = 1;
private:
uint8_t state_;
};
/**
* @brief A constructor used to create a <b>UIScrollView</b> instance, with both horizontal and vertical scrolls
* supported.
*
* @since 1.0
* @version 1.0
*/
UIScrollView();
/**
* @brief A destructor used to delete the <b>UIScrollView</b> instance.
*
* @since 1.0
* @version 1.0
*/
virtual ~UIScrollView() {}
/**
* @brief Obtains the view type.
* @return Returns the view type, as defined in {@link UIViewType}.
*
* @since 1.0
* @version 1.0
*/
UIViewType GetViewType() const override
{
return UI_SCROLL_VIEW;
}
#if defined(ENABLE_ROTATE_INPUT) && ENABLE_ROTATE_INPUT
bool OnRotateEvent(const RotateEvent& event) override;
bool OnRotateEndEvent(const RotateEvent& event) override;
#endif
bool OnDragEvent(const DragEvent& event) override;
bool OnDragEndEvent(const DragEvent& event) override;
bool OnPressEvent(const PressEvent& event) override;
/**
* @brief Scrolls the content of this view.
*
* @param xDistance Indicates the offset distance by which the content is scrolled on the x-axis.
* @param yDistance Indicates the offset distance by which the content is scrolled on the y-axis.
* @since 1.0
* @version 1.0
*/
void ScrollBy(int16_t xDistance, int16_t yDistance);
/**
* @brief Sets whether a horizontal scroll is enabled.
*
* @param state Specifies whether a horizontal scroll is enabled. <b>true</b> indicates a horizontal scroll is
* enabled, and <b>false</b> indicates the opposite case.
* @since 1.0
* @version 1.0
*/
void SetHorizontalScrollState(bool state)
{
if (direction_ == VERTICAL || direction_ == HORIZONTAL_AND_VERTICAL) {
direction_ = state ? HORIZONTAL_AND_VERTICAL : VERTICAL;
} else {
direction_ = state ? HORIZONTAL : HORIZONTAL_NOR_VERTICAL;
}
}
/**
* @brief Checks whether a horizontal scroll is enabled.
*
* @return Returns <b>true</b> if a horizontal scroll is enabled; returns <b>false</b> otherwise.
* @since 1.0
* @version 1.0
*/
bool GetHorizontalScrollState() const
{
return (direction_ == HORIZONTAL || direction_ == HORIZONTAL_AND_VERTICAL);
}
/**
* @brief Sets whether a vertical scroll is enabled.
*
* @param state Specifies whether a vertical scroll is enabled. <b>true</b> indicates a vertical scroll is enabled,
* and <b>false</b> indicates the opposite case.
* @since 1.0
* @version 1.0
*/
void SetVerticalScrollState(bool state)
{
if (direction_ == HORIZONTAL || direction_ == HORIZONTAL_AND_VERTICAL) {
direction_ = state ? HORIZONTAL_AND_VERTICAL : HORIZONTAL;
} else {
direction_ = state ? VERTICAL : HORIZONTAL_NOR_VERTICAL;
}
}
/**
* @brief Checks whether a vertical scroll is enabled.
*
* @return Returns <b>true</b> if a vertical scroll is enabled, returns <b>false</b> otherwise.
* @since 1.0
* @version 1.0
*/
bool GetVerticalScrollState() const
{
return (direction_ == VERTICAL || direction_ == HORIZONTAL_AND_VERTICAL);
}
/**
* @brief Registers a listener that contains a callback to be invoked upon scroll state changes.
*
* @param scrollListener Indicates the listener to register. For details, see {@link OnScrollListener}.
* @since 1.0
* @version 1.0
*/
void RegisterScrollListener(OnScrollListener* scrollListener)
{
scrollListener_ = scrollListener;
}
protected:
void StopAnimator() override;
bool DragXInner(int16_t distance) override;
bool DragYInner(int16_t distance) override;
bool MoveOffset(int16_t offsetX, int16_t offsetY);
private:
void Drag(const DragEvent& event);
void CalculateReboundDistance(int16_t& dragDistanceX, int16_t& dragDistanceY) override;
void RefreshScrollBar();
OnScrollListener* scrollListener_;
#if defined(ENABLE_VIBRATOR) && ENABLE_VIBRATOR
int16_t totalRotateLen_;
int16_t lastVibratorRotateLen_;
void SetIsEdge(bool& lastIsEdge, Rect childRect);
#endif
};
} // namespace OHOS
#endif // GRAPHIC_LITE_UI_SCROLL_VIEW_H