As Marco Zhou has said in the msdn forum
(http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/b2428b85-adc9-4a1e-a588-8dbb3b9aac06/):
Windows will only send WM_IME_SETCONTEXT message to the active window,
Popup by default is designed to be shown with WM_EX_NOACTIVE which
means that it doesn’t in active state when displaying, that’s why IME
could not work correctly in this regard, to workaround this issue, you
could try set the Popup as the active window using win32
SetActiveWindow() API.

As Marco Zhou has said in the msdn forum
(http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/b2428b85-adc9-4a1e-a588-8dbb3b9aac06/):
Windows will only send WM_IME_SETCONTEXT message to the active window,
Popup by default is designed to be shown with WM_EX_NOACTIVE which
means that it doesn’t in active state when displaying, that’s why IME
could not work correctly in this regard, to workaround this issue, you
could try set the Popup as the active window using win32
SetActiveWindow() API.

So the workaround is use MyPopup instead of Popup:

So the workaround is use MyPopup instead of Popup:

public class MyPopup : Popup
{
    [DllImport(“user32.dll”)]
    static extern IntPtr SetActiveWindow(IntPtr hWnd);

public class MyPopup : Popup
{
    [DllImport(“user32.dll”)]
    static extern IntPtr SetActiveWindow(IntPtr hWnd);

    static MyPopup()
    {
        EventManager.RegisterClassHandler(
            typeof(MyPopup),
            Popup.PreviewGotKeyboardFocusEvent,
            new
KeyboardFocusChangedEventHandler(OnPreviewGotKeyboardFocus),
            true);
    }

    static MyPopup()
    {
        EventManager.RegisterClassHandler(
            typeof(MyPopup),
            Popup.PreviewGotKeyboardFocusEvent,
            new
KeyboardFocusChangedEventHandler(OnPreviewGotKeyboardFocus),
            true);
    }

    private static void OnPreviewGotKeyboardFocus(Object sender,
KeyboardFocusChangedEventArgs e)
    {
        var textBox = e.NewFocus as TextBoxBase;
        if (textBox != null)
        {
            var hwndSource = PresentationSource.FromVisual(textBox) as
HwndSource;
            if (hwndSource != null)
            {
                SetActiveWindow(hwndSource.Handle);
            }
        }
    }
}

    private static void OnPreviewGotKeyboardFocus(Object sender,
KeyboardFocusChangedEventArgs e)
    {
        var textBox = e.NewFocus as TextBoxBase;
        if (textBox != null)
        {
            var hwndSource = PresentationSource.FromVisual(textBox) as
HwndSource;
            if (hwndSource != null)
            {
                SetActiveWindow(hwndSource.Handle);
            }
        }
    }
}

官解决方案

官解决方案

利用的讲话自己修一个好像代码如齐,控件内local:MyPopup
等同于Popup,亲测好要,实用。

运的言语自己建一个接近代码如达到,控件内local:MyPopup
等同于Popup,亲测好而,实用。

参考:https://connect.microsoft.com/VisualStudio/feedback/details/389998/wpf-popup-messes-with-ime-switching

参考:https://connect.microsoft.com/VisualStudio/feedback/details/389998/wpf-popup-messes-with-ime-switching