2008年（909）
分类：
2008-05-06 22:03:22
一、概述
MDI窗口包含一个框架窗口和若干子窗口。
实际上，框架窗口本身是一个普通主窗口，不过它的客户去被一个特殊窗口覆盖。
这个特殊窗口是系统预定义的“窗口类”，类名称为："MDICLIENT"。它负责各个MDI子窗口的管理。
二、窗口建立
1.注册一个MDI框架窗口类，提供MDI框架窗口消息处理函数
MDI框架窗口消息处理函数中，将未处理消息交由DefFrameProc处理
//MDI框架窗口消息处理函数
LRESULT CALLBACK MDIFrameWndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
//...
//其他消息交给由系统提供的缺省框架处理函数DefFrameProc
//其中，第二个参数是客户区窗口句柄
return ::DefFrameProc (hwnd,hwndClient, message, wParam, lParam) ;
}
2.注册多个MDI子窗口类、对应提供各MDI子窗口的消息处理函数//MDI子窗口消息处理函数
LRESULT CALLBACK MDIChildWndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
//...
//...
//其他消息交给由系统提供的缺省MDI子窗口处理函数
return ::DefMDIChildProc (hwnd, message, wParam, lParam) ;
}
3.在框架窗口的客户区建立MDI管理子窗口在主窗口收到WM_CREATE消息后:
case WM_CREATE:
{
hinst=((LPCREATESTRUCT) lParam)->hInstance;
//填充CLIENTCREATESTRUCT结构
CLIENTCREATESTRUCT clientcreate ;
clientcreate.hWindowMenu = hMenuInitWindow ; //用于添加窗口列表的菜单句柄
clientcreate.idFirstChild = 50000 ; //起始ID
hwndClient =CreateWindowEx(0,
"MDICLIENT", //类名称为"MDICLIENT"
NULL,
WS_CHILD |WS_CLIPCHILDREN| WS_VISIBLE,
0,
0,
0,
0,
hwnd,
(HMENU)1,//ID
hinst, //实例句柄
&clientcreate); //参数
}
return 0;
窗口的大小没有关系，缺省的框架窗口消息处理函数为让它覆盖整个客户区。
4.MDI子窗口的建立
可以在菜单中添加命令项，以建立子窗口。
框架窗口的消息处理函数收到命令后，向MDI客户区窗口发建立命令。
case ID_NEW:
{
MDICREATESTRUCT mdicreate;
mdicreate.szClass = szMDIChildName ; //MDI子窗口的类名称
mdicreate.szTitle = TEXT ("Hello") ;
mdicreate.hOwner = hinst ;
mdicreate.x = CW_USEDEFAULT ;
mdicreate.y = CW_USEDEFAULT ;
mdicreate.cx = CW_USEDEFAULT ;
mdicreate.cy = CW_USEDEFAULT ;
mdicreate.style = 0 ;
mdicreate.lParam = 0 ;
SendMessage (
hwndClient, //MDI客户区窗口句柄
WM_MDICREATE, //创建MDI子窗口
0,
(LPARAM) (LPMDICREATESTRUCT) &mdicreate //创建参数
) ;
}
break;
三、消息循环中处理针对MDI的热键while (GetMessage (&msg, NULL, 0, 0))
{
if (!TranslateMDISysAccel (hwndClient, &msg) &&
!TranslateAccelerator (hwndFrame, hAccel, &msg))
{
TranslateMessage (&msg) ;
DispatchMessage (&msg) ;
}
}
四、命令的流向case WM_COMMAND:
switch (LOWORD (wParam))
{
//针对框架的命令
case ID_ONE:
//...
return 0;
//针对MDI子窗口管理的命令
case IDM_WINDOW_TILE:
SendMessage (hwndClient, WM_MDITILE, 0, 0) ;
return 0 ;
//针对子窗口的命令又子窗口去处理
default:
hwndChild = (HWND) SendMessage (hwndClient,
WM_MDIGETACTIVE, 0, 0) ;
if (IsWindow (hwndChild))
SendMessage (hwndChild, WM_COMMAND, wParam, lParam) ;
break ; //..and then to DefFrameProc
}
break ; //跳出针对WM_COMMAND的case分支，又DefFrameProc处理剩下的命令
五、子窗口的管理case WM_COMMAND:
switch (LOWORD (wParam))
{
case IDM_WINDOW_TILE:
SendMessage (hwndClient, WM_MDITILE, 0, 0) ;
return 0 ;
case IDM_WINDOW_CASCADE:
SendMessage (hwndClient, WM_MDICASCADE, 0, 0) ;
return 0 ;
case IDM_WINDOW_ARRANGE:
SendMessage (hwndClient, WM_MDIICONARRANGE, 0, 0) ;
return 0;
//...
//...
}
break;
2.当前子窗口的关闭如果用户直接按下子窗口的关闭按钮，则WM_CLOSE消息直接发送到了子窗口消息处理函数。
例如:
框架窗口命令处理中:
case IDM_FILE_CLOSE:
//获得当前激活窗口
hwndChild = (HWND) SendMessage (hwndClient, WM_MDIGETACTIVE, 0, 0);
//询问通过后，销毁窗口
if (SendMessage (hwndChild, WM_QUERYENDSESSION, 0, 0))
SendMessage (hwndClient, WM_MDIDESTROY, (WPARAM) hwndChild, 0);
return 0;子窗口的消息处理函数中:LRESULT CALLBACK HelloWndProc (HWND hwnd, UINT message,
WPARAM wParam, LPARAM lParam)
{
switch (message)
{
//...
//...
case WM_QUERYENDSESSION:
case WM_CLOSE:
if (IDOK != MessageBox (hwnd, TEXT ("OK to close window?"),
TEXT ("Hello"),
MB_ICONQUESTION | MB_OKCANCEL))
return 0 ;
break ; // i.e., call DefMDIChildProc
}
return DefMDIChildProc (hwnd, message, wParam, lParam) ;
}
3.关闭所有子窗口case IDM_WINDOW_CLOSEALL: //针对所有子窗口执行CloseEnumProc EnumChildWindows (hwndClient, CloseEnumProc, 0) ; return 0 ;枚举函数:
BOOL CALLBACK CloseEnumProc (HWND hwnd, LPARAM lParam)
{
if (GetWindow (hwnd, GW_OWNER)) // Check for icon title
return TRUE ;
SendMessage (GetParent (hwnd), WM_MDIRESTORE, (WPARAM) hwnd, 0) ;
if (!SendMessage (hwnd, WM_QUERYENDSESSION, 0, 0))
return TRUE ;
SendMessage (GetParent (hwnd), WM_MDIDESTROY, (WPARAM) hwnd, 0) ;
return TRUE ;
}
六、菜单控制case WM_MDIACTIVATE:
//激活时，设置框架菜单
if (lParam == (LPARAM) hwnd)
SendMessage (hwndClient, WM_MDISETMENU,
(WPARAM) hMenuHello, (LPARAM) hMenuHelloWindow) ;
//失去焦点时，将框架菜单还原
if (lParam != (LPARAM) hwnd)
SendMessage (hwndClient, WM_MDISETMENU, (WPARAM) hMenuInit,
(LPARAM) hMenuInitWindow) ;
DrawMenuBar (hwndFrame) ;
//注: hwndFrame的得到方法:
//hwndClient = GetParent (hwnd) ;
//hwndFrame = GetParent (hwndClient) ;
return 0 ;
(全文完)
下载本文示例代码