Question

我正在学习Win32 API。我创建了一个空窗口，并在其中添加了一个编辑框以输入一些文本。我可以在其中键入文本，但无法切换键盘语言。

Alt + Shift等快捷方式不起作用。如果我单击托盘中的语言图标，它将暂停几秒钟，然后它将最终打开列表，但我的窗口将变为非活动状态，因此更改不会影响它。

如果我这样做，我可以改变语言：

按Alt + Shift（或任何组合）
按Alt，Space

通常，在左上方的窗口菜单中弹出第2步，但同时步骤1也将变为实际步骤。

我想，我没有处理某种消息，或者创建错误的窗口，但我找不到错误的内容。这是完整的代码：

#include <windows.h>

// handle of the edit box
HWND testEditBox;

// shows a message
void showMessage( LPSTR message ){
    MessageBox( GetActiveWindow(), message, "", MB_OK );
}

// a simple window procedure
LRESULT CALLBACK windowProc( HWND window, UINT message, WPARAM wparam, LPARAM lparam )
{
    switch( message )
    {
        case WM_CLOSE:
            DestroyWindow( window );
            break;
        case WM_DESTROY:
            PostQuitMessage( 0 );
            break;
        default:
            return DefWindowProc( window, message, wparam, lparam );
    }
    return 0;
}

int WINAPI WinMain( HINSTANCE instance, HINSTANCE prevInstance, LPSTR commandLine, int showMode )
{
    // create window class
    WNDCLASS windowClass;
    windowClass.cbClsExtra = 0;
windowClass.cbWndExtra = 0;
windowClass.style = 0;
    windowClass.hInstance = instance;
    windowClass.hCursor = LoadCursor( NULL, IDC_ARROW );
    windowClass.hbrBackground = (HBRUSH)(COLOR_BTNFACE + 1);
    windowClass.hIcon = LoadIcon( NULL, IDI_APPLICATION );
    windowClass.lpszClassName = "testWindow";
    windowClass.lpfnWndProc = windowProc;

    if( !RegisterClass( &windowClass ) )
    {
        showMessage( "Some trouble, sir" );
        return GetLastError();
    }

    HWND window = CreateWindow
    (
        "testWindow",
        "Test Window",
        WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT,
        400, 300,
        NULL, // no parent
        NULL, // no menu
        instance,
        NULL // no 'window-creation data'
    );

    if( !window ){
        showMessage( "Some trouble, sir" );
        return GetLastError();
    }

    ShowWindow( window, showMode );


    // add an EDIT box to our window
    testEditBox = CreateWindow
    (
        "EDIT",
        "input here",
        WS_CHILD,
        10, 10,
        200, 20,
        window,
        NULL,
        instance,
        NULL
    );
    ShowWindow( testEditBox, SW_SHOW );

    // start message loop
    MSG message;
    while( GetMessage( &message, window, 0, 0 ) > 0 )
    {
        TranslateMessage( &message );
        DispatchMessage( &message );
    }


    return message.wParam;
}

Answer 1

问题出在GetMessage( &message, window, 0, 0 )行。您只收到window的邮件，而不是testEditBox，因此不会分派某些邮件。该行应该像GetMessage(&message, NULL, 0, 0)。

当我按下并释放 Ctrl + Shift 时，这些是testEditBox在您的应用程序中收到的消息：

WM_KEYDOWN nVirtKey:VK_CONTROL cRepeat:1 ScanCode:1D fExtended:0 fAltDown:0 fRepeat:0 fUp:0
WM_KEYDOWN nVirtKey:VK_SHIFT cRepeat:1 ScanCode:2A fExtended:0 fAltDown:0 fRepeat:0 fUp:0
WM_KEYUP nVirtKey:VK_SHIFT cRepeat:1 ScanCode:2A fExtended:0 fAltDown:0 fRepeat:1 fUp:1
WM_KEYUP nVirtKey:VK_CONTROL cRepeat:1 ScanCode:1D fExtended:0 fAltDown:0 fRepeat:1 fUp:1

将它们与修复后的消息进行比较：

WM_KEYDOWN nVirtKey:VK_CONTROL cRepeat:1 ScanCode:1D fExtended:0 fAltDown:0 fRepeat:0 fUp:0
WM_KEYDOWN nVirtKey:VK_SHIFT cRepeat:1 ScanCode:2A fExtended:0 fAltDown:0 fRepeat:0 fUp:0
WM_KEYUP nVirtKey:VK_SHIFT cRepeat:1 ScanCode:2A fExtended:0 fAltDown:0 fRepeat:1 fUp:1
WM_IME_NOTIFY dwCommand:IMN_CLOSESTATUSWINDOW dwData:00000000
WM_IME_NOTIFY dwCommand:IMN_OPENSTATUSWINDOW dwData:00000000
WM_INPUTLANGCHANGE charset:0 hkl:04090409 //this
WM_IME_NOTIFY dwCommand:IMN_SETCOMPOSITIONFONT dwData:00000000
WM_KEYUP nVirtKey:VK_CONTROL cRepeat:1 ScanCode:1D fExtended:0 fAltDown:0 fRepeat:1 fUp:1

窗口处于活动状态时无法切换键盘语言

1 个答案: