效果：

 

1.定义两个个定时器ID  

#define ID_TIMER_DISPLAY_DELAY 30#define ID_TIMER_DISPLAY_CLOSE 40

 

2.添加一个成员函数和成员变量

void SetAlpha(HWND hWnd,int Alpha);int m_nFlag ;

void CPopUpWnd::SetAlpha(HWND hWnd,int Alpha)

{

  HINSTANCE hInst = LoadLibrary(L"User32.DLL");

  if(hInst)

  {

    typedef BOOL (WINAPI *MYFUNC)(HWND,COLORREF,BYTE,DWORD);

    MYFUNC fun = NULL;

   //取得SetLayeredWindowAttributes函数指针

   fun=(MYFUNC)GetProcAddress(hInst, "SetLayeredWindowAttributes");

   if(fun)fun(hWnd,0,Alpha,2);

   FreeLibrary(hInst);

   }

}

3.修改窗口属性

void CPopUpWnd::OnPrepare(){    //直接显示在右下角    MoveSelfWindow();    //修改窗口属性为了窗口透明度    SetWindowLong(m_hWnd,GWL_EXSTYLE,GetWindowLong(m_hWnd,GWL_EXSTYLE)^0x80000);

     //3秒后改变窗口透明度

     SetTimer(m_hWnd,ID_TIMER_DISPLAY_DELAY,3000,NULL);

}

4.在定时器响应函数里

 

LRESULT CPopUpWnd::OnTimer(UINT uMsg, WPARAM wParam, LPARAM lParam,BOOL& bHandled){        switch(wParam)    {
    //多个定时器        case ID_TIMER_DISPLAY_DELAY:        KillTimer(m_hWnd,ID_TIMER_DISPLAY_DELAY);        SetTimer(m_hWnd,ID_TIMER_DISPLAY_CLOSE,60,NULL);        break;    case ID_TIMER_DISPLAY_CLOSE:        {            if(m_nFlag < 255)            {                m_nFlag+= 5;                SetAlpha(m_hWnd,255-m_nFlag);            }            else            {                KillTimer(m_hWnd,ID_TIMER_DISPLAY_CLOSE);                Close(IDCLOSE);                m_nFlag = 0;            }        }        break;    }    return 0;}

 

5.窗口渐变关闭过程中，鼠标经过窗口，关闭定时器，窗口恢复原状

LRESULT CPopUpWnd::OnMouseEnter(UINT uMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled){       .....        //KillTimer(m_hWnd,ID_TIMER_DISPLAY_DELAY);    KillTimer(m_hWnd,ID_TIMER_DISPLAY_CLOSE);    if (m_nFlag < 255)    {        SetAlpha(m_hWnd,255);    }      ....    return 0;}

6.鼠标出了窗口，开启定时器继续渐变关闭窗口

LRESULT CPopUpWnd::OnMouseLeave(UINT uMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled){    .....    SetTimer(m_hWnd,ID_TIMER_DISPLAY_CLOSE,30,NULL);    m_nFlag = 0;       ....    return 0;}