CCMenu解析

代码：

/** @brief A Menu for touch handling.* * Features and Limitation:*  - You can add MenuItem objects in runtime using addChild.*  - But the only accepted children are MenuItem objects.*/// 处理触摸事件的菜单// 特点和限制：可以在运行的时候使用addChild添加MenuItem对象// 但是，只能添加MenuItem类型的对象class CC_DLL Menu : public Layer{public:    /**     * Menu state, it's used internally.     */    enum class State    {        WAITING,        TRACKING_TOUCH,    };        /**     *@brief Creates an empty Menu.     */ // 创建一个菜单    static Menu* create();    #if (CC_TARGET_PLATFORM == CC_PLATFORM_WP8) || (CC_TARGET_PLATFORM == CC_PLATFORM_WINRT)    // WP8 in VS2012 does not support nullptr in variable args lists and variadic templates are also not supported.    typedef MenuItem* M;    static Menu* create(M m1, std::nullptr_t listEnd) { return variadicCreate(m1, NULL); }    static Menu* create(M m1, M m2, std::nullptr_t listEnd) { return variadicCreate(m1, m2, NULL); }    static Menu* create(M m1, M m2, M m3, std::nullptr_t listEnd) { return variadicCreate(m1, m2, m3, NULL); }    static Menu* create(M m1, M m2, M m3, M m4, std::nullptr_t listEnd) { return variadicCreate(m1, m2, m3, m4, NULL); }    static Menu* create(M m1, M m2, M m3, M m4, M m5, std::nullptr_t listEnd) { return variadicCreate(m1, m2, m3, m4, m5, NULL); }    static Menu* create(M m1, M m2, M m3, M m4, M m5, M m6, std::nullptr_t listEnd) { return variadicCreate(m1, m2, m3, m4, m5, m6, NULL); }    static Menu* create(M m1, M m2, M m3, M m4, M m5, M m6, M m7, std::nullptr_t listEnd) { return variadicCreate(m1, m2, m3, m4, m5, m6, m7, NULL); }    static Menu* create(M m1, M m2, M m3, M m4, M m5, M m6, M m7, M m8, std::nullptr_t listEnd) { return variadicCreate(m1, m2, m3, m4, m5, m6, m7, m8, NULL); }    static Menu* create(M m1, M m2, M m3, M m4, M m5, M m6, M m7, M m8, M m9, std::nullptr_t listEnd) { return variadicCreate(m1, m2, m3, m4, m5, m6, m7, m8, m9, NULL); }    static Menu* create(M m1, M m2, M m3, M m4, M m5, M m6, M m7, M m8, M m9, M m10, std::nullptr_t listEnd) { return variadicCreate(m1, m2, m3, m4, m5, m6, m7, m8, m9, m10,  NULL); }    // On WP8 for lists longer than 10 items, use createWithArray or variadicCreate with NULL as the last argument.    static Menu* variadicCreate(MenuItem* item, ...);#else    /** Creates a Menu with MenuItem objects. */    static Menu* create(MenuItem* item, ...) CC_REQUIRES_NULL_TERMINATION;#endif    /**      * Creates a Menu with a Array of MenuItem objects.     * @js NA     */ // 通过MenuItem数组创建一个菜单    static Menu* createWithArray(const Vector<MenuItem*>& arrayOfItems);    /**     * Creates a Menu with it's item, then use addChild() to add      * other items. It is used for script, it can't init with undetermined     * number of variables.     * @js NA     */    static Menu* createWithItem(MenuItem* item);        /** Creates a Menu with MenuItem objects.     * @js NA     */    static Menu* createWithItems(MenuItem *firstItem, va_list args);    /** Align items vertically. */// 在竖直方向上拍成一条线    void alignItemsVertically();    /** Align items vertically with padding.    @since v0.7.2    */// 在竖直方向上拍成一条线，同时有内边距    void alignItemsVerticallyWithPadding(float padding);    /** Align items horizontally. */// 在水平方向上拍成一条线    void alignItemsHorizontally();        /** Align items horizontally with padding.    @since v0.7.2    */// 在水平方向上拍成一条线，同时有内边距    void alignItemsHorizontallyWithPadding(float padding);    /** Align items in rows of columns. */// 将项目列为行    void alignItemsInColumns(int columns, ...) CC_REQUIRES_NULL_TERMINATION;        /** Align items in rows of columns. */    void alignItemsInColumns(int columns, va_list args);        /** Align items in array of columns.     * @js NA     */ // 将项目拍成一列，通过行数组    void alignItemsInColumnsWithArray(const ValueVector& rows);    /** Align items in columns of rows. */    void alignItemsInRows(int rows, ...) CC_REQUIRES_NULL_TERMINATION;        /** Align items in columns of rows. */    void alignItemsInRows(int rows, va_list args);        /** Align items in array of rows.     * @js NA     */ // 将项目拍成行    void alignItemsInRowsWithArray(const ValueVector& columns);    /**     * Determines if the menu is enable.     * @see `setEnabled(bool)`.     * @return whether the menu is enabled or not.     */ // 是否可用    virtual bool isEnabled() const { return _enabled; }    /**     * Set whether the menu is visible.     * The default value is true, a menu is default to visible.     *@param value true if menu is enable, false if menu is disable.     */ // 设置是否可用    virtual void setEnabled(bool value) { _enabled = value; };    virtual bool onTouchBegan(Touch* touch, Event* event) override;    virtual void onTouchEnded(Touch* touch, Event* event) override;    virtual void onTouchCancelled(Touch* touch, Event* event) override;    virtual void onTouchMoved(Touch* touch, Event* event) override;        // overrides    virtual void removeChild(Node* child, bool cleanup) override;        virtual void addChild(Node * child) override;    virtual void addChild(Node * child, int zOrder) override;    virtual void addChild(Node * child, int zOrder, int tag) override;    virtual void addChild(Node * child, int zOrder, const std::string &name) override;        virtual void onEnter() override;    virtual void onExit() override;    virtual void setOpacityModifyRGB(bool bValue) override {CC_UNUSED_PARAM(bValue);}    virtual bool isOpacityModifyRGB(void) const override { return false;}    virtual std::string getDescription() const override;CC_CONSTRUCTOR_ACCESS:    /**     * @js ctor     */    Menu() : _selectedItem(nullptr) {}    virtual ~Menu();    /** initializes an empty Menu */    bool init() override;    /** initializes a Menu with a NSArray of MenuItem objects */    bool initWithArray(const Vector<MenuItem*>& arrayOfItems);protected:    /** whether or not the menu will receive events */    bool _enabled;    MenuItem* getItemForTouch(Touch * touch);    State _state;    MenuItem *_selectedItem;private:    CC_DISALLOW_COPY_AND_ASSIGN(Menu);};