cocos2dx 源码分析 之Widget 头文件 （3.11.1）

//一直想找时间梳理下，虽然我可能讲的不好，但多写多讲才会进步啊！嗯，厚脸皮的试试。
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#ifndef __UIWIDGET_H__
#define __UIWIDGET_H__

#include "2d/CCProtectedNode.h"
#include "ui/UILayoutParameter.h"
#include "ui/GUIDefine.h"
#include "ui/GUIExport.h"
#include "base/CCMap.h"

/**
 * @addtogroup ui
 * @{
 */
NS_CC_BEGIN
// 单点触摸事件
class EventListenerTouchOneByOne;
// 摄像机
class Camera;

namespace ui {
    class LayoutComponent;

/**
 * Touch event type.
 *@deprecated use `Widget::TouchEventType` instead
 */
// 触摸事件的事件名枚举 分别是 开始点击 移动 离开 不正常离开属于取消
typedef enum
{
    TOUCH_EVENT_BEGAN,TOUCH_EVENT_MOVED,TOUCH_EVENT_ENDED,TOUCH_EVENT_CANCELED
}TouchEventType;
    
/**
 * Touch event callback.
 *@deprecated use `Widget::ccWidgetTouchCallback` instead
 */
// 触摸事件回调处理
typedef void (Ref::*SEL_TouchEvent)(Ref*,TouchEventType);
#define toucheventselector(_SELECTOR) (SEL_TouchEvent)(&_SELECTOR)
#if (CC_TARGET_PLATFORM == CC_PLATFORM_WINRT)
#ifdef ABSOLUTE
#undef ABSOLUTE
#endif
#endif

/** 
*@brief Base class for all ui widgets. 
* This class inherent from `ProtectedNode` and `LayoutParameterProtocol`. 
* If you want to implements your own ui widget,you should subclass it. 
*/
class CC_GUI_DLL Widget : public ProtectedNode,public LayoutParameterProtocol
{
public: 
    /** 
    * Widget focus direction. 
    */
    enum class FocusDirection 
    {
        LEFT,RIGHT,UP,DOWN 
    }; 

    /** 
    * Widget position type for layout. 
    */
    // 坐标的方式，前者是标准化，直接设置坐标的数字，
    // 第二种是按照比例，以父节点大小为参考，设置百分比来作为坐标，好处是可以不用get一下父节点的大小再来设置具体数字，而且父节点大小修改的时候不需要再调整一次位置
    enum class PositionType 
    { 
        ABSOLUTE,PERCENT 
    }; 

    /** 
    * Widget size type for layout. 
    */
    // 类似上面的，坐标换为大小而已
    enum class SizeType
    {
        ABSOLUTE,PERCENT
    };
    
    /**
     * Touch event type.
     */
    // 有点跟上面重复？这是为啥
    enum class TouchEventType
    {
        BEGAN,MOVED,ENDED,CANCELED
    };
    
    /**
     * Texture resource type.
     * - LOCAL:  It means the texture is loaded from image.
     * - PLIST: It means the texture is loaded from texture atlas.
     */
    // 纹理加载的两个方式
    // 默认是 传入图片路径
    // 第二种是序列帧里使用的 把碎图合在大图里，但使用的时候只是要其中一项，使用前要先放入帧缓存中，再用plist里面的名字把它拿出来用
    enum class TextureResType
    {
        LOCAL = 0,PLIST = 1
    };
    
    /**
     * Widget bright style.
     */
    enum class BrightStyle
    {
        NONE = -1,NORMAL,HIGHLIGHT
    };

    
    /**
     * Widget touch event callback.
     */
    // 触摸事件的回调
    typedef std::function<void(Ref*,Widget::TouchEventType)> ccWidgetTouchCallback; 
    
    /** 
    * Widget click event callback. 
    */
    // 点击事件的回调
    typedef std::function<void(Ref*)> ccWidgetClickCallback; 

    /** 
    * Widget custom event callback. 
    * It is mainly used together with Cocos Studio. 
    */
    // cocostudio里面注册事件的回调
    typedef std::function<void(Ref*,int)> ccWidgetEventCallback; 

    /** 
    * Default constructor 
    * @js ctor 
    * @lua new 
    */ 
    Widget(void); 

    /** 
    * Default destructor 
    * @js NA 
    * @lua NA 
    */ 
    virtual ~Widget(); 

    /** 
    * Create and return a empty Widget instance pointer. 
    */
    // 创建
    static Widget* create();

    /**
     * Sets whether the widget is enabled
     * 
     * true if the widget is enabled,widget may be touched,false if the widget is disabled,widget cannot be touched.
     *
     * Note: If you want to change the widget's appearance  to disabled state,you should also call  `setBright(false)`.
     *
     * The default value is true,a widget is default to enable touch.
     *
     * @param enabled Set to true to enable touch,false otherwise.
     */
    // UI组件特有的基本属性,CC类是没有的  _enabled  用来控制是否接收触摸事件（当_visible和_enabled都为true才接收触摸)

    virtual void setEnabled(bool enabled);

    /**
     * Determines if the widget is enabled or not.
     *
     * @return true if the widget is enabled,false if the widget is disabled.
     */
    bool isEnabled() const;

    /**
     * Sets whether the widget is bright
     *
     * The default value is true,a widget is default to bright
     *
     * @param bright   true if the widget is bright,false if the widget is dark.
     */
    // UI组件特有的基本属性,CC类是没有的 用于按钮等需要切换状态的
    // 相关接口onPressStateChangedToNormal() onPressStateChangedToPressed() onPressStateChangedToDisabled()
    void setBright(bool bright);

    /**
     * Determines if the widget is bright
     *
     * @return true if the widget is bright,false if the widget is dark.
     */
    bool isBright() const;

    /**
     * Sets whether the widget is touch enabled.
     *
     * The default value is false,a widget is default to touch disabled.
     *
     * @param enabled   True if the widget is touch enabled,false if the widget is touch disabled.
     */
    // UI组件特有的基本属性,CC类是没有的  _touchEnabled  能否点击 注册点击事件
    virtual void setTouchEnabled(bool enabled);

    /**
     * To set the bright style of widget.
     *
     * @see BrightStyle
     *
     * @param style   BrightStyle::NORMAL means the widget is in normal state,BrightStyle::HIGHLIGHT means the widget is in highlight state.
     */
    void setBrightStyle(BrightStyle style);

    /**
     * Determines if the widget is touch enabled
     *
     * @return true if the widget is touch enabled,false if the widget is touch disabled.
     */
    bool isTouchEnabled() const;

    /**
     * Determines if the widget is highlighted
     *
     * @return true if the widget is highlighted,false if the widget is not highlighted.
     */
    bool isHighlighted() const;

    /**
     * Sets whether the widget is highlighted
     *
     * The default value is false,a widget is default to not highlighted
     *
     * @param highlight   true if the widget is highlighted,false if the widget is not highlighted.
     */
    void setHighlighted(bool highlight);

    /**
     * Gets the left boundary position of this widget in parent's coordination system.
     * @deprecated use `getLeftBoundary` instead.
     * @return The left boundary position of this widget.
     */
    // 获取本身最左边的x坐标
    CC_DEPRECATED_ATTRIBUTE float getLeftInParent(){return this->getLeftBoundary();}

    /**
     * Gets the left boundary position of this widget in parent's coordination system.
     * @return The left boundary position of this widget.
     */
    // 获取本身最左边的x坐标
    float getLeftBoundary() const; 

    /** 
    * Gets the bottom boundary position of this widget in parent's coordination system. 
    * @deprecated use `getBottomBoundary` instead. 
    * @return The bottom boundary position of this widget. 
    */
    // 获取本身最下边的y坐标
    CC_DEPRECATED_ATTRIBUTE float getBottomInParent(){return this->getBottomBoundary();} 

    /** 
    * Gets the bottom boundary position of this widget in parent's coordination system. 
    * @return The bottom boundary position of this widget. 
    */
    // 获取本身最下边的y坐标
    float getBottomBoundary() const; 

    /** 
    * Gets the right boundary position of this widget in parent's coordination system. 
    * @deprecated use `getRightBoundary` instead. 
    * @return The right boundary position of this widget. 
    */
    // 获取本身最右边的x坐标
    CC_DEPRECATED_ATTRIBUTE float getRightInParent(){return this->getRightBoundary();} 

    /** 
    * Gets the right boundary position of this widget in parent's coordination system. 
    * @return The right boundary position of this widget. 
    */
    // 获取本身最右边的x坐标
    float getRightBoundary() const; 

    /** 
    * Gets the top boundary position of this widget in parent's coordination system. 
    * @deprecated use `getTopBoundary` instead. 
    * @return The top boundary position of this widget. 
    */
    // 获取本身最上边的y坐标
    CC_DEPRECATED_ATTRIBUTE float getTopInParent(){return this->getTopBoundary();} 

    /** 
    * Gets the top boundary position of this widget in parent's coordination system. 
    * @return The top boundary position of this widget. 
    */
    // 获取本身最上边的y坐标
    float getTopBoundary() const; 

    /** 
    * @js NA 
    */
    // 遍历树
    virtual void visit(cocos2d::Renderer *renderer,const Mat4 &parentTransform,uint32_t parentFlags) override;

    /**
     * Sets the touch event target/selector to the widget
     */
    CC_DEPRECATED_ATTRIBUTE void addTouchEventListener(Ref* target,SEL_TouchEvent selector);
    /**
     * Set a callback to touch vent listener.
     *@param callback  The callback in `ccWidgetEventCallback.`
     */
    //触摸回调
    void addTouchEventListener(const ccWidgetTouchCallback& callback);
    
    /**
     * Set a click event handler to the widget.
     * @param callback The callback in `ccWidgetClickCallback`.
     */
    // 点击回调
    void addClickEventListener(const ccWidgetClickCallback& callback);
    /**
     * Set a event handler to the widget in order to use cocostudio editor and framework
     * @param callback The callback in `ccWidgetEventCallback`.
     * @lua NA
     */
    // cocostudio 里面的回调
    virtual void addCCSEventListener(const ccWidgetEventCallback& callback);
    /**/

    /**
     * Changes the position (x,y) of the widget in OpenGL coordinates
     *
     * Usually we use p(x,y) to compose a Vec2 object.
     * The original point (0,0) is at the left-bottom corner of screen.
     *
     * @param pos  The position (x,y) of the widget in OpenGL coordinates
     */
    virtual void setPosition(const Vec2 &pos) override;

    /**
     * Set the percent(x,y) of the widget in OpenGL coordinates
     *
     * @param percent  The percent (x,y) of the widget in OpenGL coordinates
     */
    void setPositionPercent(const Vec2 &percent);

    /**
     * Gets the percent (x,y) of the widget in OpenGL coordinates
     *
     * @see setPosition(const Vec2&)
     *
     * @return The percent (x,y) of the widget in OpenGL coordinates
     */
    const Vec2& getPositionPercent();

    /**
     * Changes the position type of the widget
     *
     * @see `PositionType`
     *
     * @param type  the position type of widget
     */
    void setPositionType(PositionType type);

    /**
     * Gets the position type of the widget
     *
     * @see `PositionType`
     *
     * @return type  the position type of widget
     */
    PositionType getPositionType() const;

    /**
     * Sets whether the widget should be flipped horizontally or not.
     *
     * @param flippedX true if the widget should be flipped horizontally,false otherwise.
     */
    // 设置节点x方向翻转
    virtual void setFlippedX(bool flippedX);

    /**
     * Returns the flag which indicates whether the widget is flipped horizontally or not.
     *
     * It not only flips the texture of the widget,but also the texture of the widget's children.
     * Also,flipping relies on widget's anchor point.
     * Internally,it just use setScaleX(-1) to flip the widget.
     *
     * @return true if the widget is flipped horizontally,false otherwise.
     */
    virtual bool isFlippedX()const{return _flippedX;};

    /**
     * Sets whether the widget should be flipped vertically or not.
     *
     * @param flippedY true if the widget should be flipped vertically,false otherwise.
     */
    // 设置节点y方向翻转 其实是用scale实现
    virtual void setFlippedY(bool flippedY); 

    /** 
    * Return the flag which indicates whether the widget is flipped vertically or not. 
    * 
    * It not only flips the texture of the widget,but also the texture of the widget's children. * Also,flipping relies on widget's anchor point. 
    * Internally,it just use setScaleY(-1) to flip the widget. * * @return true if the widget is flipped vertically,false otherwise. 
    */
    virtual bool isFlippedY()const{return _flippedY;}; 

    /** @deprecated Use isFlippedX() instead */ 
    CC_DEPRECATED_ATTRIBUTE bool isFlipX() { return isFlippedX(); }; 

    /** @deprecated Use setFlippedX() instead */ 
    CC_DEPRECATED_ATTRIBUTE void setFlipX(bool flipX) { setFlippedX(flipX); }; 

    /** @deprecated Use isFlippedY() instead */ 
    CC_DEPRECATED_ATTRIBUTE bool isFlipY() { return isFlippedY(); }; 

    /** @deprecated Use setFlippedY() instead */
    CC_DEPRECATED_ATTRIBUTE void setFlipY(bool flipY) { setFlippedY(flipY); };
    // 节点放缩
    //override the setScale function of Node
    virtual void setScaleX(float scaleX) override;
    virtual void setScaleY(float scaleY) override;
    virtual void setScale(float scale) override;
    virtual void setScale(float scalex,float scaley) override;
    using Node::setScaleZ;
    virtual float getScaleX() const override;
    virtual float getScaleY() const override;
    virtual float getScale() const override;
    using Node::getScaleZ;
    
    /**
     * Checks a point if in parent's area.
     *
     * @param pt A point in `Vec2`.
     * @deprecated  use `isClippingParentContainsPoint` instead.
     * @return true if the point is in parent's area,false otherwise.
     */
    CC_DEPRECATED_ATTRIBUTE bool clippingParentAreaContainPoint(const Vec2 &pt){return this->isClippingParentContainsPoint(pt);}

    /**
     * Checks a point if in parent's area.
     *
     * @param pt A point in `Vec2`.
     * @return true if the point is in parent's area,false otherwise.
     */
    // 判断是否有父辈亲属是带有裁剪功能的Layout且包含某个点 用于判断裁剪组件是否可以接收这个点
    bool isClippingParentContainsPoint(const Vec2& pt);

    /**
     * Gets the touch began point of widget when widget is selected.
     * @deprecated use `getTouchBeganPosition` instead.
     * @return the touch began point.
     */
    CC_DEPRECATED_ATTRIBUTE const Vec2& getTouchStartPos()const{return this->getTouchBeganPosition();}
    /**
     * Gets the touch began point of widget when widget is selected.
     * @return the touch began point.
     */
    // 挺常用的功能 获取触摸开始的点坐标
    const Vec2& getTouchBeganPosition()const;

    /*
     * Gets the touch move point of widget when widget is selected.
     * @deprecated use `getTouchMovePosition` instead.
     * @return the touch move point.
     */
    CC_DEPRECATED_ATTRIBUTE const Vec2& getTouchMovePos()const{ return this->getTouchMovePosition();}
    /*
     * Gets the touch move point of widget when widget is selected.
     * @return the touch move point.
     */
    // 挺常用的功能 获取上一个触摸移动的点坐标
    const Vec2& getTouchMovePosition()const; 

    /* 
    * Gets the touch end point of widget when widget is selected. 
    * @deprecated use `getTouchEndPosition` instead. 
    * @return the touch end point. 
    */ 
    CC_DEPRECATED_ATTRIBUTE const Vec2& getTouchEndPos()const{return this->getTouchEndPosition();} 

    /* 
    * Gets the touch end point of widget when widget is selected. 
    * @return the touch end point. 
    */
    // 挺常用的功能 获取触摸结束的点坐标
    const Vec2& getTouchEndPosition()const; 

    /** 
    * Changes the size that is widget's size * @deprecated use `setContentSize` instead. 
    * @param size that is widget's size 
    */
    CC_DEPRECATED_ATTRIBUTE virtual void setSize(const Size &size); 

    /** 
    * Changes the size that is widget's size 
    * @param contentSize A content size in `Size`. 
    */
    // 设置大小
    // 区分下几个size
    // _contentSize 是Node都有的属性 代表节点的大小
    // _customSize 是ui组件特有的 代表设置的大小，不一定是实际大小 由于widget的功能需求 后面遇到再讲解
    virtual void setContentSize(const Size& contentSize) override;

    /**
     * Changes the percent that is widget's percent size
     *
     * @param percent that is widget's percent size
     */
    virtual void setSizePercent(const Vec2 &percent);

    /**
     * Changes the size type of widget.
     *
     * @see `SizeType`
     *
     * @param type that is widget's size type
     */
    void setSizeType(SizeType type);

    /**
     * Gets the size type of widget.
     *
     * @see `SizeType`
     */
    SizeType getSizeType() const;

    /**
     * Get the size of widget
     *
     * @return Widget content size.
     */
    CC_DEPRECATED_ATTRIBUTE const Size& getSize() const;
    
    /**
     * Get the user defined widget size.
     *@return User defined size.
     */
    const Size& getCustomSize() const;
    
    /**
     * Get the content size of widget.
     * @warning This API exists mainly for keeping back compatibility.
     * @return 
     */
    virtual const Size& getLayoutSize() {return _contentSize;};

    /**
     * Get size percent of widget.
     *
     * @return Percent size.
     */
    const Vec2& getSizePercent();

    /**
     * Checks a point is in widget's content space.
     * This function is used for determining touch area of widget.
     *
     * @param pt        The point in `Vec2`.
     * @param camera    The camera look at widget,used to convert GL screen point to near/far plane.
     * @param p         Point to a Vec3 for store the intersect point,if don't need them set to nullptr.
     * @return true if the point is in widget's content space,false otherwise.
     */
    // 挺重要的一个接口 用于触摸判断点是否在节点范围内
    virtual bool hitTest(const Vec2 &pt,const Camera* camera,Vec3 *p) const;

    /**
     * A callback which will be called when touch began event is issued.
     *@param touch The touch info.
     *@param unusedEvent The touch event info.
     *@return True if user want to handle touches,false otherwise.
     */
    // 开始触摸事件处理
    virtual bool onTouchBegan(Touch *touch,Event *unusedEvent);

    /**
     * A callback which will be called when touch moved event is issued.
     *@param touch The touch info.
     *@param unusedEvent The touch event info.
     */
    // 移动触摸事件处理
    virtual void onTouchMoved(Touch *touch,Event *unusedEvent); 

    /** 
    * A callback which will be called when touch ended event is issued. 
    *@param touch The touch info. *@param unusedEvent The touch event info. 
    */
    // 结束触摸事件处理
    virtual void onTouchEnded(Touch *touch,Event *unusedEvent); 

    /** 
    * A callback which will be called when touch cancelled event is issued. 
    *@param touch The touch info. *@param unusedEvent The touch event info. 
    */
    // 取消触摸事件处理
    virtual void onTouchCancelled(Touch *touch,Event *unusedEvent); 

    /** 
    * Sets a LayoutParameter to widget. 
    * 
    * @see LayoutParameter * @param parameter LayoutParameter pointer 
    */
    // 设置Layout的一些属性 用于排列 后面遇到再细讲
    void setLayoutParameter(LayoutParameter* parameter);

    /**
     * Gets LayoutParameter of widget.
     *
     * @see LayoutParameter
     * @return LayoutParameter
     */
    LayoutParameter* getLayoutParameter()const override;
    /**
     * Gets LayoutParameter of widget.
     *
     * @see LayoutParameter
     * @deprecated use `getLayoutParameter()` instead.
     * @param type  Relative or Linear
     * @return LayoutParameter
     */
    CC_DEPRECATED_ATTRIBUTE LayoutParameter* getLayoutParameter(LayoutParameter::Type type);


    /**
     * Toggle whether ignore user defined content size for widget.
     * Set true will ignore user defined content size which means 
     * the widget size is always equal to the return value of `getVirtualRendererSize`.
     *
     * @param ignore set member variable _ignoreSize to ignore
     */
    // 因为这个功能 所以才要分出 _customSize 
    // 当_ignoreSize 为true的时候不管之前设置的数据，直接用getVirtualRendererSize为节点大小 false的时候用回之前设置的大小 所以要有_customSize来记录
    // 我记得这样迂回的设计出过bug 想到的时候再补充吧，嗯，好的
    virtual void ignoreContentAdaptWithSize(bool ignore);

    /**
     * Query whether the widget ignores user defined content size or not
     *
     * @return True means ignore user defined content size,false otherwise.
     */
    bool isIgnoreContentAdaptWithSize() const;

    /**
     * Gets position of widget in world space.
     *
     * @return Position of widget in world space.
     */
    // 世界坐标
    Vec2 getWorldPosition()const;

    /**
     * Gets the inner Renderer node of widget.
     *
     * For example,a button's Virtual Renderer is it's texture renderer.
     *
     * @return Node pointer.
     */
    // 之前2.x的时候这个是实际的节点
    virtual Node* getVirtualRenderer();


    /**
     *  Get the virtual renderer's size
     *@return Widget virtual renderer size.
     */
    virtual Size getVirtualRendererSize() const;
    

    /**
     * Returns the string representation of widget class name
     * @return get the class description.
     */
    // 描述
    virtual std::string getDescription() const override;

    /**
     * Create a new widget copy of the original one.
     * @return A cloned widget copy of original.
     */
    // ui组件特性之一 可复制
    Widget* clone();
    /**
     * @lua NA
     */
    // node的属性之一 重写的子节点需要调一次父节点 只有在切换场景的时候 进入新场景 在 Director::setNextScene() 调一次 并递归遍历下达每一个Node上
    virtual void onEnter() override;
    
    /**
     * @lua NA
     */
    // 类似上 移除旧场景的时候被调用
    virtual void onExit() override;

    /**
     * Update all children's contents size and position recursively.
     * @see `updateSizeAndPosition(const Size&)`
     */
    void updateSizeAndPosition();

    /**
     * Update all children's contents size and position recursively.
     */
    // 更新自身的大小与位置
    void updateSizeAndPosition(const Size& parentSize);
    
    /**
     * Set the tag of action.
     *@param tag  A integer tag value.
     */
    // 我一直以为actionTag是跟在action身上的 
    void setActionTag(int tag);

    /**
     * Get the action tag.
     *@return Action tag.
     */
    int getActionTag()const;
    
    /**
     * @brief Allow widget touch events to propagate to its parents. Set false will disable propagation
     * @param isPropagate  True to allow propagation,false otherwise.
     * @since v3.3
     */
    // 设置穿透触摸点 一般触摸点只有一个能接收，如果设置穿透，就可以多个节点接收，特别在多个滚动条嵌套的时候，不能穿透的话下面的滚动层根本接收不到
    void setPropagateTouchEvents(bool isPropagate);
    
    /**
     * Return whether the widget is propagate touch events to its parents or not
     * @return whether touch event propagation is allowed or not.
     * @since v3.3
     */
     
    bool isPropagateTouchEvents()const;
    
    /**
     * Toggle widget swallow touch option.
     * @brief Specify widget to swallow touches or not
     * @param swallow True to swallow touch,false otherwise.
     * @since v3.3
     */
    //其实是设置 _touchListener的吞噬特性，如果你先设置这个再设置addTouchListener就呵呵了，所以要注意顺序哦
    void setSwallowTouches(bool swallow);
    
    /**
     * Return whether the widget is swallowing touch or not
     * @return Whether touch is swallowed.
     * @since v3.3
     */
    bool isSwallowTouches()const;
    
    /**
     * Query whether widget is focused or not.
     *@return  whether the widget is focused or not
     */
    //_focusedWidget  _focusNavigationController 是全局变量 唯一性
    // 其实是Layout的一个功能
    bool isFocused()const;
    
    /**
     * Toggle widget focus status.
     *@param focus  pass true to let the widget get focus or pass false to let the widget lose focus
     *@return void
     */
    void setFocused(bool focus);
    
    /**
     * Query widget's focus enable state.
     *@return true represent the widget could accept focus,false represent the widget couldn't accept focus
     */
    bool isFocusEnabled()const;
    
    /**
     * Allow widget to accept focus.
     *@param enable pass true/false to enable/disable the focus ability of a widget
     *@return void
     */
    void setFocusEnabled(bool enable);
    
    /**
     *  When a widget is in a layout,you could call this method to get the next focused widget within a specified direction. 
     *  If the widget is not in a layout,it will return itself
     *@param direction the direction to look for the next focused widget in a layout
     *@param current  the current focused widget
     *@return the next focused widget in a layout
     */
    virtual Widget* findNextFocusedWidget(FocusDirection direction,Widget* current);
    
    /**
     * when a widget calls this method,it will get focus immediately.
     */
    void requestFocus();

    /**
     * Return a current focused widget in your UI scene.
     * No matter what widget object you call this method on,it will return you the exact one focused widget.
     * @param isWidget  if your set isWidget to true,it will return the _realFocusedWidget which is always a widget
     *                  otherwise,it will return a widget or a layout.
     * @deprecated use `getCurrentFocusedWidget` instead.
     */
    CC_DEPRECATED_ATTRIBUTE Widget* getCurrentFocusedWidget(bool isWidget){
        CC_UNUSED_PARAM(isWidget);
        return getCurrentFocusedWidget();
    }

    /**
     * Return a current focused widget in your UI scene.
     * No matter what widget object you call this method on,it will return you the exact one focused widget.
     */
    static Widget* getCurrentFocusedWidget();

    /*
     *  Call this method with parameter true to enable the Android Dpad focus navigation feature
     *@param enable  set true to enable dpad focus navigation,otherwise disenable dpad focus navigation
     */
    static void enableDpadNavigation(bool enable);

    /**
     * When a widget lose/get focus,this method will be called. Be Caution when you provide your own version,* you must call widget->setFocused(true/false) to change the focus state of the current focused widget;
     */
    std::function<void(Widget*,Widget*)> onFocusChanged;

    /**
     * use this function to manually specify the next focused widget regards to each direction
     */
    std::function<Widget*(FocusDirection)> onNextFocusedWidget;
    
    /**
     *Toggle use unify size.
     *@param enable True to use unify size,false otherwise.
     *@return void
     */
// 吐槽下 <span style="font-family: Arial,Helvetica,sans-serif;">_unifySize居然是bool 这又是实习生的锅么</span>

    void setUnifySizeEnabled(bool enable);

    /**
     * Query whether unify size enable state. 
     *@return true represent the widget use Unify Size,false represent the widget couldn't use Unify Size
     */
    bool isUnifySizeEnabled()const;

    /**
     * Set callback name.
     *@param callbackName A string representation of callback name.
     */
    // 用在ccs里面的
    void setCallbackName(const std::string& callbackName) { _callbackName = callbackName; }


    /**
     * Query callback name.
     *@return The callback name.
     */
    const std::string& getCallbackName() const{ return _callbackName; }
    
    /**
     * Set callback type.
     * @param callbackType A string representation of callback type.
     */
    // 同上
    void setCallbackType(const std::string& callbackType) { _callbackType = callbackType; }

    /**
     * Query callback type.
     *@return Callback type string.
     */
    const std::string& getCallbackType() const{ return _callbackType; }

    /**
     * Toggle layout component enable.
     *@param enable Layout Component of a widget
     *@return void
     */
    // 用于ccs
    void setLayoutComponentEnabled(bool enable);

    /**
     * Query whether layout component is enabled or not. 
     *@return true represent the widget use Layout Component,false represent the widget couldn't use Layout Component.
     */
    bool isLayoutComponentEnabled()const;

CC_CONSTRUCTOR_ACCESS:

    //initializes state of widget.
    virtual bool init() override;

    /*
     * @brief Sends the touch event to widget's parent,if a widget wants to handle touch event under another widget,*        it must override this function.
     * @param  event  the touch event type,it could be BEGAN/MOVED/CANCELED/ENDED
     * @param parent
     * @param point
     */
    // 拦截触摸点
    virtual void interceptTouchEvent(TouchEventType event,Widget* sender,Touch *touch);
    
    /**
     *@brief Propagate touch events to its parents
     */
    void propagateTouchEvent(TouchEventType event,Touch *touch);
    
    friend class PageView;
    /**
     * This method is called when a focus change event happens
     *@param widgetLostFocus  The widget which lose its focus
     *@param widgetGetFocus  The widget which get its focus
     *@return void
     */
    void onFocusChange(Widget* widgetLostFocus,Widget* widgetGetFocus);
    
    /**
     * Dispatch a EventFocus through a EventDispatcher
     *@param widgetLoseFocus  The widget which lose its focus
     *@param widgetGetFocus he widget which get its focus
     *@return void
     */
    void  dispatchFocusEvent(Widget* widgetLoseFocus,Widget* widgetGetFocus);
    
protected:
    /**
     * Get a normal state GLProgramState
     *@since v3.4
     */
    
    GLProgramState* getNormalGLProgramState()const;
    
    /**
     * Get a disabled state GLProgramState
     *@since v3.4
     */
    GLProgramState* getGrayGLProgramState()const;
     
    // 调整大小 例如可以加dirty属性 只调整一次之类的
    //call back function called when size changed.
    virtual void onSizeChanged();
    //  ui组件特有 新建ui组件记得重写这个
    //initializes renderer of widget.
    virtual void initRenderer();

    //call back function called widget's state changed to normal.
    virtual void onPressStateChangedToNormal();
    //call back function called widget's state changed to selected.
    virtual void onPressStateChangedToPressed();
    //call back function called widget's state changed to dark.
    virtual void onPressStateChangedToDisabled();

    void pushDownEvent();
    void moveEvent();

    virtual void releaseUpEvent();
    virtual void cancelUpEvent();

    // 状态调整
    virtual void adaptRenderers(){};
    void updateChildrenDisplayedRGBA();
    
    // ui组件特性 clone属性附带接口
    void copyProperties(Widget* model);
    virtual Widget* createCloneInstance();
    virtual void copySpecialProperties(Widget* model);
    virtual void copyClonedWidgetChildren(Widget* model);
    
    Widget* getWidgetParent();
    void updateContentSizeWithTextureSize(const Size& size);
    
    // 递归判断是否父辈亲属都是_enabled 属性true 一个false则为false
    bool isAncestorsEnabled();
    Widget* getAncensterWidget(Node* node);
    bool isAncestorsVisible(Node* node);

    void cleanupWidget();
    LayoutComponent* getOrCreateLayoutComponent();

protected:
    bool _usingLayoutComponent;
    bool _unifySize;
    bool _enabled;
    bool _bright;
    bool _touchEnabled;
    bool _highlight;
    bool _affectByClipping;
    bool _ignoreSize;
    bool _propagateTouchEvents;

    BrightStyle _brightStyle;
    SizeType _sizeType;
    PositionType _positionType;

    //used for search widget by action tag in UIHelper class
    int _actionTag;

    Size _customSize;

    Vec2 _sizePercent;
    Vec2 _positionPercent;

    bool _hitted;
    // weak reference of the camera which made the widget passed the hit test when response touch begin event
    // it's useful in the next touch move/end events
    const Camera *_hittedByCamera;
    EventListenerTouchOneByOne* _touchListener;
    Vec2 _touchBeganPosition;
    Vec2 _touchMovePosition;
    Vec2 _touchEndPosition;

    bool _flippedX;
    bool _flippedY;

    //use map to enable switch back and forth for user layout parameters
    Map<int,LayoutParameter*> _layoutParameterDictionary;
    LayoutParameter::Type _layoutParameterType;

    bool _focused;
    bool _focusEnabled;
    /**
     * store the only one focused widget
     */
    static Widget *_focusedWidget;  //both layout & widget will be stored in this variable

    Ref*       _touchEventListener;
    #if defined(__GNUC__) && ((__GNUC__ >= 4) || ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 1)))
    #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
    #elif _MSC_VER >= 1400 //vs 2005 or higher
    #pragma warning (push)
    #pragma warning (disable: 4996)
    #endif
    SEL_TouchEvent    _touchEventSelector;
    #if defined(__GNUC__) && ((__GNUC__ >= 4) || ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 1)))
    #pragma GCC diagnostic warning "-Wdeprecated-declarations"
    #elif _MSC_VER >= 1400 //vs 2005 or higher
    #pragma warning (pop)
    #endif
    ccWidgetTouchCallback _touchEventCallback;
    ccWidgetClickCallback _clickEventListener;
    ccWidgetEventCallback _ccEventCallback;
    
    std::string _callbackType;
    std::string _callbackName;
private:
    class FocusNavigationController;
    static FocusNavigationController* _focusNavigationController;
};
}

NS_CC_END
// end of ui group
/// @}

#endif /* defined(__Widget__) */

（编辑：李大同）

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