请问C语言如何实现多个窗口的嵌套？

Question

我在学习C语言win窗口编程的时候，写了如下基础的程序：

#include "windows.h"

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) {
    WNDCLASS wc_1;
    WNDCLASS wc_2;

    static TCHAR* NAME_1 = TEXT("one");
    static TCHAR* NAME_2 = TEXT("two");

    HWND hwnd_1 = NULL;
    HWND hwnd_2 = NULL;

    MSG msg_1;
    MSG mag_2;

    wc_1.style = CS_HREDRAW | CS_VREDRAW; //窗口样式
    wc_1.lpfnWndProc = WndProc; //过程函数
    wc_1.cbClsExtra = 0; //扩展字段
    wc_1.cbWndExtra = 0; //扩展字段
    wc_1.hInstance = hInstance; //当前实例句柄
    wc_1.hIcon = LoadIcon(hInstance, IDI_APPLICATION); //设置程序图标
    wc_1.hCursor = LoadCursor(NULL, IDC_ARROW); //设置鼠标
    wc_1.hbrBackground = (HBRUSH) GetStockObject(BLACK_BRUSH);
    wc_1.lpszMenuName = NULL;
    wc_1.lpszClassName = NAME_1;

    RegisterClass(&wc_1);
    RegisterClass(&wc_2);

    hwnd_1 = CreateWindow(NAME_1, //要注册的窗口类名
                        TEXT("The first window"),//窗口标题
                        WS_OVERLAPPEDWINDOW, //窗口样式
                        CW_USEDEFAULT, //窗口距离屏幕左上角都横坐标
                        CW_USEDEFAULT, //窗口距离屏幕左上角都纵坐标
                        400, //窗口宽度
                        300, //窗口高度
                        NULL, //父窗口句柄
                        NULL, //菜单句柄
                        hInstance, //当前实例句柄
                        NULL); //指向一个值的指针，该值传递给窗口 WM_CREATE消息。一般为NULL
                        
    ShowWindow(hwnd_1, iCmdShow);

    UpdateWindow(hwnd_1);

    while (GetMessage(&msg_1, NULL, 0, 0)) {
        TranslateMessage(&msg_1);
        DispatchMessage(&msg_1);
    }

    return msg_1.wParam;
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) {
    switch (message) {
        case WM_DESTROY:
            PostQuitMessage(0);
            break;
    }
    return DefWindowProc(hwnd, message, wParam, lParam);
}

这样只能得到一个黑黢黢的窗口，没有什么用途。为了学习我下载了一款定时打铃的简易软件，用vs的spy++工具发现这个程序可以在一个窗口内嵌套另一些别的窗口：

在大窗口内存在很多小窗口，它们有的窗口类是一样的，但句柄都是不一样的，这样有很多窗口就可以让这个程序更加美观，功能更齐全，使用起来更方便。

请问使用C语言如何才可以实现这种窗口的嵌套，并实现多功能美观的应用程序？感谢！

Answer 1

参考GPT和自己的思路：实现窗口嵌套需要在窗口过程函数中处理WM_CREATE消息，以创建子窗口，并在父窗口的WM_SIZE消息中调整子窗口的大小和位置。以下是一个简单的示例代码，可以创建两个嵌套的窗口。

#include <windows.h>

LRESULT CALLBACK ParentWndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK ChildWndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) {
    WNDCLASS wc;
    HWND hwndParent, hwndChild;
    MSG msg;

    // 注册父窗口类
    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.lpfnWndProc = ParentWndProc;
    wc.cbClsExtra = 0;
    wc.cbWndExtra = 0;
    wc.hInstance = hInstance;
    wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    wc.lpszMenuName = NULL;
    wc.lpszClassName = TEXT("ParentWndClass");
    RegisterClass(&wc);

    // 注册子窗口类
    wc.lpfnWndProc = ChildWndProc;
    wc.lpszClassName = TEXT("ChildWndClass");
    RegisterClass(&wc);

    // 创建父窗口
    hwndParent = CreateWindow(TEXT("ParentWndClass"), TEXT("Parent Window"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 400, 300, NULL, NULL, hInstance, NULL);

    // 创建子窗口
    hwndChild = CreateWindow(TEXT("ChildWndClass"), TEXT("Child Window"), WS_CHILD | WS_VISIBLE, 50, 50, 200, 150, hwndParent, NULL, hInstance, NULL);

    ShowWindow(hwndParent, iCmdShow);
    UpdateWindow(hwndParent);

    // 消息循环
    while (GetMessage(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    return (int)msg.wParam;
}

LRESULT CALLBACK ParentWndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {
    switch (msg) {
        case WM_CREATE:
            // 创建子窗口
            CreateWindow(TEXT("ChildWndClass"), TEXT("Child Window"), WS_CHILD | WS_VISIBLE, 50, 50, 200, 150, hwnd, NULL, ((LPCREATESTRUCT)lParam)->hInstance, NULL);
            break;

        case WM_SIZE:
            // 调整子窗口的大小和位置
            MoveWindow(GetDlgItem(hwnd, 1), 50, 50, LOWORD(lParam) - 100, HIWORD(lParam) - 100, TRUE);
            break;

        case WM_DESTROY:
            PostQuitMessage(0);
            break;

        default:
            return DefWindowProc(hwnd, msg, wParam, lParam);
    }

    return 0;
}

LRESULT CALLBACK ChildWndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {
    switch (msg) {
        case WM_CREATE:
            break;

        case WM_PAINT:
            {
                PAINTSTRUCT ps;
                HDC hdc = BeginPaint(hwnd, &ps);
                TextOut(hdc, 10, 10, TEXT("Hello from child window!"), 25);
EndPaint(hwnd, &ps);
}
break;
case WM_DESTROY:
        PostQuitMessage(0);
        break;

    default:
        return DefWindowProc(hwnd, msg, wParam, lParam);
}

return 0;
}
LRESULT CALLBACK ParentWndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {
static HWND child_hwnd = NULL;
switch (msg) {
    case WM_CREATE:
        {
            WNDCLASS wc = { 0 };

            wc.style = CS_HREDRAW | CS_VREDRAW;
            wc.lpfnWndProc = ChildWndProc;
            wc.hInstance = (HINSTANCE)GetWindowLongPtr(hwnd, GWLP_HINSTANCE);
            wc.lpszClassName = TEXT("Child");

            RegisterClass(&wc);

            child_hwnd = CreateWindow(TEXT("Child"), TEXT("Child Window"),
                WS_CHILD | WS_VISIBLE, 50, 50, 200, 200,
                hwnd, NULL, wc.hInstance, NULL);
        }
        break;

    case WM_PAINT:
        {
            PAINTSTRUCT ps;
            HDC hdc = BeginPaint(hwnd, &ps);
            TextOut(hdc, 10, 10, TEXT("Hello from parent window!"), 27);
            EndPaint(hwnd, &ps);
        }
        break;

    case WM_DESTROY:
        PostQuitMessage(0);
        break;

    default:
        return DefWindowProc(hwnd, msg, wParam, lParam);
}

return 0;
}
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) {
static TCHAR szAppName[] = TEXT("Parent");
HWND hwnd;
MSG msg;
WNDCLASS wndclass;
wndclass.style = CS_HREDRAW | CS_VREDRAW;
wndclass.lpfnWndProc = ParentWndProc;
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hInstance = hInstance;
wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
wndclass.lpszMenuName = NULL;
wndclass.lpszClassName = szAppName;

if (!RegisterClass(&wndclass)) {
    MessageBox(NULL, TEXT("This program requires Windows NT!"), szAppName, MB_ICONERROR);
    return 0;
}

hwnd = CreateWindow(szAppName, TEXT("The Hello Program"), WS_OVERLAPPEDWINDOW,
    CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
    NULL, NULL, hInstance, NULL);

ShowWindow(hwnd, iCmdShow);
UpdateWindow(hwnd);

while (GetMessage(&msg, NULL, 0, 0)) {
    TranslateMessage(&msg);
    DispatchMessage(&msg);
}

return msg.wParam;
}