Win32应用中创建多窗口

Win32应用中创建多窗口，创建同一个窗口类的多个窗口对象和不同窗口类的窗口对象。

// win32_多窗口.cpp : Defines the entry point for the application.
//

#include "stdafx.h"
#include "resource.h"

#define MAX_LOADSTRING 100

// Global Variables:
HINSTANCE hInst;                                // current instance
TCHAR szTitle[MAX_LOADSTRING];                    // The title bar text
TCHAR szTitle2[MAX_LOADSTRING] = {"同一个窗口类的第二个窗口"};
TCHAR szTitle3[MAX_LOADSTRING] = {"不同窗口类的窗口"};
TCHAR szWindowClass[MAX_LOADSTRING];            // The title bar text
TCHAR szWindowClass2[MAX_LOADSTRING] = {"Submarine"};    // 第二个窗口类的类名
HWND hWnd, hWnd2, hWnd3;                        // 保存窗口句柄

// Foward declarations of functions included in this code module:
ATOM                MyRegisterClass(HINSTANCE hInstance);
BOOL                InitInstance(HINSTANCE, int);
LRESULT CALLBACK    WndProc(HWND, UINT, WPARAM, LPARAM);
LRESULT CALLBACK    WndProc2(HWND, UINT, WPARAM, LPARAM);
LRESULT CALLBACK    About(HWND, UINT, WPARAM, LPARAM);

int APIENTRY WinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR     lpCmdLine,
                     int       nCmdShow)
{
     // TODO: Place code here.
    MSG msg;
    HACCEL hAccelTable;

    // Initialize global strings
    LoadString(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);
    LoadString(hInstance, IDC_WIN32_, szWindowClass, MAX_LOADSTRING);
    MyRegisterClass(hInstance);

    // Perform application initialization:
    if (!InitInstance (hInstance, nCmdShow)) 
    {
        return FALSE;
    }

    hAccelTable = LoadAccelerators(hInstance, (LPCTSTR)IDC_WIN32_);

    // Main message loop:
    while (GetMessage(&msg, NULL, 0, 0)) 
    {
        if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg)) 
        {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }
    }

    return msg.wParam;
}



//
//  FUNCTION: MyRegisterClass()
//
//  PURPOSE: Registers the window class.
//
//  COMMENTS:
//
//    This function and its usage is only necessary if you want this code
//    to be compatible with Win32 systems prior to the 'RegisterClassEx'
//    function that was added to Windows 95. It is important to call this function
//    so that the application will get 'well formed' small icons associated
//    with it.
//
ATOM MyRegisterClass(HINSTANCE hInstance)
{
    WNDCLASSEX wcex, wcex2;

    // 第一个窗口类的定义
    wcex.cbSize = sizeof(WNDCLASSEX); 

    wcex.style            = CS_HREDRAW | CS_VREDRAW;
    wcex.lpfnWndProc    = (WNDPROC)WndProc;
    wcex.cbClsExtra        = 0;
    wcex.cbWndExtra        = 0;
    wcex.hInstance        = hInstance;
    wcex.hIcon            = LoadIcon(hInstance, (LPCTSTR)IDI_WIN32_);
    wcex.hCursor        = LoadCursor(NULL, IDC_ARROW);
    wcex.hbrBackground    = (HBRUSH)(COLOR_WINDOW+1);
    wcex.lpszMenuName    = (LPCSTR)IDC_WIN32_;
    wcex.lpszClassName    = szWindowClass;
    wcex.hIconSm        = LoadIcon(wcex.hInstance, (LPCTSTR)IDI_SMALL);

    // 第二个窗口类的定义
    wcex2.cbSize = sizeof(WNDCLASSEX); 

    wcex2.style            = CS_HREDRAW | CS_VREDRAW;
    wcex2.lpfnWndProc    = (WNDPROC)WndProc2;
    wcex2.cbClsExtra    = 0;
    wcex2.cbWndExtra    = 0;
    wcex2.hInstance        = hInstance;
    wcex2.hIcon            = LoadIcon(hInstance, (LPCTSTR)IDI_WIN32_);
    wcex2.hCursor        = LoadCursor(NULL, IDC_ARROW);
    wcex2.hbrBackground    = (HBRUSH)(COLOR_WINDOW+1);
    wcex2.lpszMenuName    = (LPCSTR)IDC_WIN32_;
    wcex2.lpszClassName    = szWindowClass2;
    wcex2.hIconSm        = LoadIcon(wcex.hInstance, (LPCTSTR)IDI_SMALL);

    return (RegisterClassEx(&wcex) && RegisterClassEx(&wcex2));
}

//
//   FUNCTION: InitInstance(HANDLE, int)
//
//   PURPOSE: Saves instance handle and creates main window
//
//   COMMENTS:
//
//        In this function, we save the instance handle in a global variable and
//        create and display the main program window.
//
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
//   HWND hWnd;

   hInst = hInstance; // Store instance handle in our global variable

   hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);
   hWnd2 = CreateWindow(szWindowClass, szTitle2, WS_OVERLAPPEDWINDOW,
      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);
   hWnd3 = CreateWindow(szWindowClass2, szTitle3, WS_OVERLAPPEDWINDOW,
      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);

   if (!hWnd || !hWnd2 || !hWnd3)
   {
      return FALSE;
   }

   ShowWindow(hWnd, nCmdShow);
   UpdateWindow(hWnd);
   ShowWindow(hWnd2, nCmdShow);
   UpdateWindow(hWnd2);
   ShowWindow(hWnd3, nCmdShow);
   UpdateWindow(hWnd3);

   return TRUE;
}

//
//  FUNCTION: WndProc(HWND, unsigned, WORD, LONG)
//
//  PURPOSE:  Processes messages for the main window.
//
//  WM_COMMAND    - process the application menu
//  WM_PAINT    - Paint the main window
//  WM_DESTROY    - post a quit message and return
//
//
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    int wmId, wmEvent;
    PAINTSTRUCT ps;
    HDC hdc;

    switch (message) 
    {
        case WM_COMMAND:
            wmId    = LOWORD(wParam); 
            wmEvent = HIWORD(wParam); 
            // Parse the menu selections:
            switch (wmId)
            {
                case IDM_ABOUT:
                   DialogBox(hInst, (LPCTSTR)IDD_ABOUTBOX, hWnd, (DLGPROC)About);
                   break;
                case IDM_EXIT:
                   DestroyWindow(hWnd);
                   break;
                default:
                   return DefWindowProc(hWnd, message, wParam, lParam);
            }
            break;
        case WM_PAINT:
            hdc = BeginPaint(hWnd, &ps);
            // TODO: Add any drawing code here...
//            RECT rt;
//            GetClientRect(hWnd, &rt);
            EndPaint(hWnd, &ps);
            break;
        case WM_DESTROY:
            PostQuitMessage(0);
            break;
        default:
            return DefWindowProc(hWnd, message, wParam, lParam);
   }
   return 0;
}

LRESULT CALLBACK WndProc2(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    int wmId, wmEvent;
    PAINTSTRUCT ps;
    HDC hdc;

    switch (message) 
    {
        case WM_COMMAND:
            wmId    = LOWORD(wParam); 
            wmEvent = HIWORD(wParam); 
            // Parse the menu selections:
            switch (wmId)
            {
                case IDM_ABOUT:
                   DialogBox(hInst, (LPCTSTR)IDD_ABOUTBOX, hWnd, (DLGPROC)About);
                   break;
                case IDM_EXIT:
                   DestroyWindow(hWnd);
                   break;
                default:
                   return DefWindowProc(hWnd, message, wParam, lParam);
            }
            break;
        case WM_PAINT:
            hdc = BeginPaint(hWnd, &ps);
            // TODO: Add any drawing code here...
//            RECT rt;
//            GetClientRect(hWnd, &rt);
            EndPaint(hWnd, &ps);
            break;
        case WM_DESTROY:
            MessageBox(hWnd, "不是同一个窗口类", "Note", MB_OK);
//            PostQuitMessage(0);        // 此处未调用该函数，应用的消息队列中也就未添加WM_QUIT消息，
                                    // 在WinMain函数的消息循环中继续等待用户或系统消息，
                                    // 消息循环没结束，整个主函数WinMan也就没结束。
            break;
        default:
            return DefWindowProc(hWnd, message, wParam, lParam);
   }
   return 0;
}

// Mesage handler for about box.
LRESULT CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)
    {
        case WM_INITDIALOG:
                return TRUE;

        case WM_COMMAND:
            if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL) 
            {
                EndDialog(hDlg, LOWORD(wParam));
                return TRUE;
            }
            break;
    }
    return FALSE;
}

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