无模态对话框

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  现在来看看CreateDialog(),它是DialogBox()的姐妹函数.区別在于DialogBox()拥有自己的消息循环并且直到对话框关闭才返回,CreateDialog()则更加像CreateWindowEx()创建的一个窗口,立即返回并向你的消息循环发送消息,就像是你的主窗口发的消息样.这就是所谓的无模态,而DialogBox()创建的是模态对话框.

  创建的资源如下:

IDD_TOOLBAR DIALOGEX 0, 0, 98, 52STYLE DS_MODALFRAME | WS_POPUP | WS_CAPTIONEXSTYLE WS_EX_TOOLWINDOWCAPTION "My Dialog Toolbar"FONT 8, "MS Sans Serif"BEGIN    PUSHBUTTON      "&Press This Button",IDC_PRESS,7,7,84,14    PUSHBUTTON      "&Or This One",IDC_OTHER,7,31,84,14END

  你可以看到资源编辑器把DIALOG換成了DIALOGEX表明我们要为我们的对话框设置扩展风格.

  接下来想在程序运行的时候创建对话框,想要对话框可视,所以在WM_CREATE的消息处理中创建它.我们也需要声明一个全局变量来保持从CreateDialog()返回的窗口句柄以便在后面使用它.DialogBox()不向我们返回句柄因为DialogBox()在窗口销毀的时候才返回.

    HWND g_hToolbar = NULL;    case WM_CREATE:        g_hToolbar = CreateDialog(GetModuleHandle(NULL), MAKEINTRESOURCE(IDD_TOOLBAR),            hwnd, ToolDlgProc);        if(g_hToolbar != NULL)        {            ShowWindow(g_hToolbar, SW_SHOW);        }        else        {            MessageBox(hwnd, "CreateDialog returned NULL", "Warning!",                  MB_OK | MB_ICONINFORMATION);        }    break;

  要检查返回值,这什么时候总是一个好的习惯,如果是正确的(不为NULL)我们就用ShowWindow()来显示这个窗口,要是用DiaglogBox(),这一步就是不必要的,因为系统为我们调用了ShowWindow().

  现在我需要为工具栏写一个对话过程.

BOOL CALLBACK ToolDlgProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam){    switch(Message)    {        case WM_COMMAND:            switch(LOWORD(wParam))            {                case IDC_PRESS:                    MessageBox(hwnd, "Hi!", "This is a message",                         MB_OK | MB_ICONEXCLAMATION);                break;                case IDC_OTHER:                    MessageBox(hwnd, "Bye!", "This is also a message",                         MB_OK | MB_ICONEXCLAMATION);                break;            }        break;        default:            return FALSE;    }    return TRUE;}

  大多数适用于DialogBox()的消息处理规则也适用于CreateDialog(),不调用DefWindowProc(),对不处理的消息返回FALSE,处理的返回TRUE.

  有个攺变就是不为无模态窗口调用EndDialog(),可以像对常规的窗口一样调用DestroyWindow().在主窗口的WndProc()中这样写...

    case WM_DESTROY:        DestroyWindow(g_hToolbar);        PostQuitMessage(0);    break;

  还有一点,希望在任何时候显示或隠藏我们的工具栏,所以我在菜单上加上了两个命令来做这件事情,并这样处理:

    case WM_COMMAND:        switch(LOWORD(wParam))        {               case ID_DIALOG_SHOW:                ShowWindow(g_hToolbar, SW_SHOW);            break;            case ID_DIALOG_HIDE:                ShowWindow(g_hToolbar, SW_HIDE);            break;            //... other command handlers        }    break;

  如果在此时运行你的程序并试图在两个按钮间切換的话,就会注意到不行,按Alt+P和Alt+O来激活按钮都不行.为什么? 因为DialogBox()有自己的消息循环并默认地处理这些事件,CreateDialog()卻沒有.但是可以通过在消息循环中调用可以为做默认处理的IsDialogMessage()来自己处理它们.

    while(GetMessage(&Msg, NULL, 0, 0))    {        if(!IsDialogMessage(g_hToolbar, &Msg))        {            TranslateMessage(&Msg);            DispatchMessage(&Msg);        }    }

  这里我们首先将消息传给IsDialogMessage(),如果消息是为工具栏的(由我们传进的窗口的句柄来指示),系统就作默认的处理并返回TRUE.这种情況下消息已经被处理了所以我们不需要再调用TranslateMessage()或DispatchMessage()了.如果消息是为另外一个窗口就照常处理.

  值得提出来的是IsDialogMessage()也可以用于不是对话框的窗口来给它们一些像对话框的功能.记住,对话框就是一个窗口,并且大多数(如果不是全部的话)对话框的API可以工作于任何窗口.

贴个完整的代码吧 有点长:

资源文件的建立如上。

#include <windows.h>#define IDD_TOOLBAR                     101#define IDC_OTHER 9003#define IDC_PRESS   9004#define ID_DIALOG_SHOW 9005#define ID_DIALOG_HIDE 9006HWND g_hToolbar = NULL;const char g_szClassName[] = "myWindowClass";BOOL CALLBACK AboutDlgProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam){switch(Message){case WM_INITDIALOG:return TRUE;case WM_COMMAND:switch(LOWORD(wParam)){case IDC_PRESS:MessageBox(hwnd,"you press a button!","this is message",MB_OK | MB_ICONINFORMATION);break;case IDC_OTHER:MessageBox(hwnd,"you press a other button!","this is message",MB_OK | MB_ICONINFORMATION);case IDOK:EndDialog(hwnd, IDOK);break;case IDCANCEL:EndDialog(hwnd, IDCANCEL);break;}break;default:return FALSE;}return TRUE;}LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam){switch(msg){case WM_CREATE:{HMENU hmenu,hSubMenu;hmenu = CreateMenu();hSubMenu = CreatePopupMenu();AppendMenu(hSubMenu,MF_STRING,ID_DIALOG_SHOW,"&Show");AppendMenu(hSubMenu,MF_STRING,ID_DIALOG_HIDE,"&Hide");AppendMenu(hmenu,MF_STRING | MF_POPUP,(UINT)hSubMenu,"&Dialog");SetMenu(hwnd,hmenu);g_hToolbar = CreateDialog(GetModuleHandle(NULL),MAKEINTRESOURCE(IDD_TOOLBAR),hwnd,AboutDlgProc);if(g_hToolbar != NULL)ShowWindow(g_hToolbar,SW_HIDE);elseMessageBox(hwnd,"CreateDialog return NULL","Warning",MB_OK | MB_ICONINFORMATION);}break;case WM_COMMAND:switch(LOWORD(wParam)){case ID_DIALOG_SHOW:ShowWindow(g_hToolbar, SW_SHOW);break;case ID_DIALOG_HIDE:ShowWindow(g_hToolbar, SW_HIDE);break;}break;case WM_LBUTTONDOWN:{char szFileName[MAX_PATH];HINSTANCE hInstance = GetModuleHandle(NULL);GetModuleFileName(hInstance, szFileName, MAX_PATH);MessageBox(hwnd, szFileName, "This program is:", MB_OK | MB_ICONINFORMATION);}break;case WM_CLOSE:DestroyWindow(hwnd);break;case WM_DESTROY:DestroyWindow(g_hToolbar);PostQuitMessage(0);break;default:return DefWindowProc(hwnd, msg, wParam, lParam);}return 0;}int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,LPSTR lpCmdLine, int nCmdShow){WNDCLASSEX wc;HWND hwnd;MSG Msg;wc.cbSize        = sizeof(WNDCLASSEX);wc.style         = 0;wc.lpfnWndProc   = WndProc;wc.cbClsExtra    = 0;wc.cbWndExtra    = 0;wc.hInstance     = hInstance;wc.hIcon         = LoadIcon(NULL, IDI_APPLICATION);wc.hCursor       = LoadCursor(NULL, IDC_ARROW);wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);wc.lpszMenuName  = NULL;wc.lpszClassName = g_szClassName;wc.hIconSm       = LoadIcon(NULL, IDI_APPLICATION);if(!RegisterClassEx(&wc)){MessageBox(NULL, "Window Registration Failed!", "Error!",MB_ICONEXCLAMATION | MB_OK);return 0;}hwnd = CreateWindowEx(WS_EX_CLIENTEDGE,g_szClassName,"The title of my window",WS_OVERLAPPEDWINDOW,CW_USEDEFAULT, CW_USEDEFAULT, 400, 400,NULL, NULL, hInstance, NULL);if(hwnd == NULL){MessageBox(NULL, "Window Creation Failed!", "Error!",MB_ICONEXCLAMATION | MB_OK);return 0;}ShowWindow(hwnd, nCmdShow);UpdateWindow(hwnd);while(GetMessage(&Msg, NULL, 0, 0) > 0){if(!IsDialogMessage(g_hToolbar,&Msg)){TranslateMessage(&Msg);DispatchMessage(&Msg);}}return Msg.wParam;}