思路来自：MFC Tutorial - Creating a window with two classes
在工程中新建一个类 CChildFrame
class CChildFrame : public CFrameWnd
在构造函数中：
1 CChildFrame::CChildFrame() 2 { 3 Create(NULL,"MFC Tutorial Part 1 CoderSource Window"); 4 }
可选：添加WM_PAINT消息：
1 void CChildFrame::OnPaint() 2 { 3 CPaintDC dc(this); // device context for painting 4 5 // TODO: Add your message handler code here 6 CDC *pDC = GetDC(); 7 8 CBrush brush(RGB(0, 0, 0)); 9 CBrush *pOldBrush = pDC->SelectObject(&brush); 10 pDC->Rectangle(0, 0, 500, 500); 11 pDC->SelectObject(pOldBrush); 12 // Do not call CFrameWnd::OnPaint() for painting messages 13 }
在CXXApp类中，添加 CChildFrame 指针变量：
1 class CXXApp : public CWinApp 2 { 3 public: 4 CChildFrame *m_pChildWnd; 5 6 ... 7 }
在CXXApp类的 InitInstance 方法中添加：
1 BOOL CMultilayerDisplayApp::InitInstance() 2 { 3 ... 4 5 m_pChildWnd = new CChildFrame(); // 创建新窗口类对象 6 //////// 这部分用于透明此窗口对象关联的窗口/////////// 7 //加入WS_EX_LAYERED扩展属性 8 SetWindowLong(m_pChildWnd->m_hWnd, GWL_EXSTYLE, GetWindowLong(m_pChildWnd->m_hWnd, GWL_EXSTYLE)^0x80000); 9 HINSTANCE hInst = LoadLibrary("User32.DLL"); 10 if (hInst) 11 { 12 typedef BOOL (WINAPI *MYFUNC)(HWND,COLORREF,BYTE,DWORD); 13 MYFUNC fun = NULL; 14 //取得SetLayeredWindowAttributes函数指针 15 fun = (MYFUNC)GetProcAddress(hInst, "SetLayeredWindowAttributes"); 16 if (fun) 17 { 18 fun(m_pChildWnd->m_hWnd, 0, 128, 2); 19 } 20 FreeLibrary(hInst); 21 } 22 //////// 这部分用于透明此窗口对象关联的窗口/////////// 23 24 // The one and only window has been initialized, so show and update it. 25 m_pMainWnd->ShowWindow(SW_SHOW); 26 m_pMainWnd->UpdateWindow(); 27 28 m_pChildWnd->ShowWindow(SW_SHOW); 29 m_pChildWnd->UpdateWindow(); 30 31 return TRUE; 32 } 33
效果如下：
