protected:

    int m_nIndex;//编号

    CDrawNode* m_pDrawObj;

    friend class CCircleTool;

};

    绘制节点的工具CCircleTool在鼠标左键按下OnLButtonDown的消息处理函数中，实际分配内存，产生一个节点对象。

2．1．2箭线类CDrawArrow的设计

class CDrawArrow: public CDrawObj

{

public:

    CDrawRect(const CRect& position);

    void SetProjectName(CString name){  m_ProjectName=name;};

    void SetProjectTime(int time) { m_ProjectTime=time;};

CString GetProjectName()  { return m_ProjectName;}

void SetProjectTime(int time){ return m_ProjectTime;}

    bool m_bForeConnect;//箭线始节点标志

    bool m_bBackConnect;//箭线终节点标志

    int m_ForeConnect; //箭线连接的始节点序号

    int m_BackConnect; //箭线连接的终节点序号

virtual int GetObjIndex() {return o};

//绘制时，计算平行于箭线的说明文字的角度，位置，项目名称总在线的上方

    virtual void Draw(CDC* pDC,CDrawView* pView);

    enum ArrowType{ none, pureArrow, openArrow,stealthArrow, diamondArrow, ovalArrow};

    enum Shape { rectangle, roundRectangle, ellipse, line,arrow };

protected:

    CString m_ProjectName;    //项目名称

    int m_ProjectTime;        //时间

    Shape m_nShape;

    ArrowType m_lArrow, m_rArrow;  //for arrow only

    int m_lArrowSize, m_rArrowSize; //for arrow only

private:

    void DrawArrow(ArrowType arrowType, POINT p1, POINT p2, int arrowSize, CDC *,int, int , int, CBrush *);

    friend class CArrowTool;

};