The current activate-deactivate-hideWindows control has the following problems:

   * hideWindows() is called while active.
   * dispatch() is called while not active.
   * When a dialog has been disposed and focus has moved to the client
     of the main Frame, it doesn't allow the client to switch input
     methods.

To reproduce those symptoms, use SwingSet and launch the Input Dialog, which causes switching between the XIM host adapter and a Java input method.