如何检测子窗口上的 WM_KEYDOWN？

Question

对于像按钮、编辑等标准控件，我可以将其子类化，但是对于子窗口（我用作容器）如何完成？我知道WM_KEYDOWN 已发送到父窗口，但我无法直接从相应的子窗口获取它。我试过子类化它（不确定这是否有意义，因为它是一个窗口并且在WNDCLASSW.lpfnWndProc 成员中已经有自己的窗口过程）但是这个子过程无论如何都没有收到WM_KEYDOWN 消息。我可以通过使用GetCursorPos() 和WindowFromPoint() 从光标位置（我也需要考虑键盘焦点）获取控件的hwnd，如下所示，但我觉得它很hacky。这样做的正确方法是什么？

目前看起来是这样的：

    case WM_KEYUP:
    case WM_KEYDOWN:
    {
        POINT p;
        if(GetCursorPos(&p))
        {
            HWND control = WindowFromPoint(p);
            if(control)
            {
                // just testing it
                int len = GetWindowTextLength(control);
                wchar_t buffer[len + 1];
                GetWindowText(control, buffer, sizeof(buffer));
                MessageBox(NULL, buffer, L"", MB_OK);
            }
        }
    }
    break;

窗口如下所示：

目标是在用户键入内容的相应窗口上捕获 WM_KEYDOWN，然后调用一个函数来处理此事件，例如window1_onKeyDown()、window2_onKeyDown() 等。

这里是完整的代码：

#pragma comment(lib, "user32.lib")
#pragma comment(lib, "Comctl32.lib")
#pragma comment(lib, "Gdi32.lib")

#define WIN32_LEAN_AND_MEAN
#define UNICODE
#define _UNICODE

#include <windows.h>

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
LRESULT CALLBACK WndProc1(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK WndProc2(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
void createWindow1(HWND);
void createWindow2(HWND);

HBRUSH hBrush1, hBrush2;

int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
                    PWSTR lpCmdLine, int nCmdShow) {

    MSG  msg;    
    WNDCLASSW wc = {0};
    wc.lpszClassName = L"my window";
    wc.hInstance     = hInstance;
    wc.hbrBackground = GetSysColorBrush(COLOR_3DFACE);
    wc.lpfnWndProc   = WndProc;
    wc.hCursor       = LoadCursor(0, IDC_ARROW);

    hBrush1 = CreateSolidBrush(RGB(173, 164, 237));
    hBrush2 = CreateSolidBrush(RGB(171, 171, 171));

    RegisterClassW(&wc);
    CreateWindowW(wc.lpszClassName, L"window",
                  WS_OVERLAPPEDWINDOW | WS_VISIBLE,
                  100, 100, 330, 270, NULL, 0, hInstance, 0);

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

    DeleteObject(hBrush1);
    DeleteObject(hBrush2);

    return (int) msg.wParam;
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, 
    WPARAM wParam, LPARAM lParam) {

    switch(msg)
    {

        case WM_CREATE:
            createWindow1(hwnd);
            createWindow2(hwnd);
        break;

      
        case WM_KEYUP:
        case WM_KEYDOWN:
        {
            POINT p;
            if(GetCursorPos(&p))
            {
                HWND control = WindowFromPoint(p);
                if(control)
                {
                    int len = GetWindowTextLength(control);
                    wchar_t buffer[len + 1];
                    GetWindowText(control, buffer, sizeof(buffer));
                    MessageBox(NULL, buffer, L"", MB_OK);
                }
            }
        }
        break;

        case WM_DESTROY:
            PostQuitMessage(0);
            break;
    }

    return DefWindowProcW(hwnd, msg, wParam, lParam);
}

void createWindow1(HWND hOwner)
{
    WNDCLASSW wc = {0};
    wc.lpszClassName = L"window2";
    wc.hInstance     = NULL;
    wc.hbrBackground = hBrush1;
    wc.lpfnWndProc   = WndProc1;
    wc.hCursor       = LoadCursor(0, IDC_ARROW);

    RegisterClassW(&wc);
    CreateWindowW(wc.lpszClassName, L"window2",
                  WS_VISIBLE | WS_TABSTOP | WS_CHILD | WS_EX_CONTROLPARENT,
                  5, 5, 200, 100, 
                  hOwner, 0, NULL, 0);
}

void createWindow2(HWND hOwner)
{
    WNDCLASSW wc = {0};
    wc.lpszClassName = L"window3";
    wc.hInstance     = NULL;
    wc.hbrBackground = hBrush2;
    wc.lpfnWndProc   = WndProc2;
    wc.hCursor       = LoadCursor(0, IDC_ARROW);

    RegisterClassW(&wc);
    CreateWindowW(wc.lpszClassName, L"window3",
                  WS_VISIBLE | WS_TABSTOP | WS_CHILD,
                  5, 120, 200, 100, 
                  hOwner, 0, NULL, 0);
}

LRESULT CALLBACK WndProc1(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{

    switch(msg)
    {
        case WM_CREATE:
            CreateWindow(L"Button", L"Button A", 
                         WS_VISIBLE | WS_TABSTOP | WS_CHILD,
                         5, 5, 80, 25,
                         hwnd, 0, NULL, 0);
        break;

        case WM_KEYUP:
        case WM_KEYDOWN:
            MessageBox(NULL, L"hello from proc1", L"", MB_OK);
            break;

        case WM_DESTROY:
            PostQuitMessage(0);
            break;
    }

    return DefWindowProcW(hwnd, msg, wParam, lParam);
}

LRESULT CALLBACK WndProc2(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) 
{

    switch(msg)
    {
        case WM_CREATE:
            CreateWindow(L"Button", L"Button ", 
                         WS_VISIBLE | WS_TABSTOP | WS_CHILD,
                         5, 5, 80, 25,
                         hwnd, 0, NULL, 0);
        break;

        case WM_DESTROY:
            PostQuitMessage(0);
            break;
    }

    return DefWindowProcW(hwnd, msg, wParam, lParam);
}

Answer 1

您可以在子窗口中使用SetFocus。

一些代码：

case WM_KEYDOWN:
    {
        POINT p;
        HWND control = GetFocus();
        if (control)
        {
            int len = GetWindowTextLength(control);
            wchar_t* buffer = new wchar_t[len + 1];
            GetWindowText(control, buffer, len + 1);
            MessageBox(NULL, buffer, L"", MB_OK);
        }
    }
    break;

LRESULT CALLBACK WndProc1(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{

    switch (msg)
    {
    case WM_CREATE:
        CreateWindow(L"Button", L"Button A",
            WS_VISIBLE | WS_TABSTOP | WS_CHILD,
            5, 5, 80, 25,
            hwnd, 0, NULL, 0);
        break;
    case WM_LBUTTONDOWN:
        SetFocus(hwnd);
        break;
    case WM_KEYUP:
    case WM_KEYDOWN:
        MessageBox(NULL, L"hello from proc1", L"", MB_OK);
        break;

    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    }

    return DefWindowProcW(hwnd, msg, wParam, lParam);
}

也可以使用current方法，然后使用PostMessage/SendMessage将WM_KEYDOWN消息转发到子窗口：

    if (control)
    {
        int len = GetWindowTextLength(control);
        wchar_t* buffer = new wchar_t[len + 1];
        GetWindowText(control, buffer, len + 1);
        MessageBox(NULL, buffer, L"", MB_OK);
        PostMessage(hwnd_child, msg, wParam, lParam);
    }