c# - 如何使用模态窗口将 WM_INPUTLANGCHANGEREQUEST 发送到应用程序？

Question

我写了一个键盘切换器，效果很好，但如果当前应用程序打开了模态窗口，它就会失败。在键盘开关上，我执行以下操作

hwnd = GetForegroundWindow();
PostMessage(hwnd, WM_INPUTLANGCHANGEREQUEST, IntPtr.Zero, handle);

在哪里

[DllImport("User32.dll", EntryPoint = "PostMessage")]
private static extern int PostMessage(IntPtr hWnd, int Msg, IntPtr wParam, IntPtr lParam);

[DllImport("user32.dll")]
static extern IntPtr GetForegroundWindow();

但语言没有改变。

我将如何完成这个？

---

添加 get root owner 改善了情况，但没有完全帮助。

添加对 GetDesktopWindow 的调用没有帮助:

hwnd = GetDesktopWindow();
InputLangChangeRequest(hwnd, language);
hwnd = GetRootOwner();
InputLangChangeRequest(hwnd, language);

---

代码在这里https://github.com/dims12/NormalKeyboardSwitcher

Answer 1

使用GetAncestor

Retrieves the owned root window by walking the chain of parent and owner windows returned by GetParent.

如果有模态窗口或模态窗口链，这应该返回主 UI 窗口。

hwnd = GetForegroundWindow();
hwnd = GetAncestor(hwnd, GA_ROOTOWNER); //#define GA_ROOTOWNER 3

---

显然，如果目标本身是基于对话框的应用程序， WM_INPUTLANGCHANGEREQUEST 会失败(我不知道为什么!)要解决此问题，您可以将 WM_INPUTLANGCHANGEREQUEST 消息发布到对话框的后代(另外到对话框本身的 WM_INPUTLANGCHANGEREQUEST 消息)

static bool MyEnumProc(IntPtr hwnd, IntPtr lParam)
{
    PostMessage(hwnd, WM_INPUTLANGCHANGEREQUEST, IntPtr.Zero, lParam);
    return true;
}

static void Foo()
{
    //Greek input for testing:
    var hkl = LoadKeyboardLayout("00000408", KLF_ACTIVATE);
    var hwnd = GetForegroundWindow();
    if (hwnd != null)
    {
        hwnd = GetAncestor(hwnd, GA_ROOTOWNER);
        PostMessage(hwnd, WM_INPUTLANGCHANGEREQUEST, IntPtr.Zero, (IntPtr)hkl);

        StringBuilder buf = new StringBuilder(100);
        GetClassName(hwnd, buf, 100);

        //if this is a dialog class then post message to all descendants 
        if (buf.ToString() == "#32770")
            EnumChildWindows(hwnd, MyEnumProc, (IntPtr)hkl);
    }
}