!7

cmodule LockScreen > DynSingleFunction {
  transient JFrame frame;
  
  visual
    withCenteredButtons(super, "Show fullscreen", rThread showFullscreen);
    
  void showFullscreen enter {
    if (frame != null) activateFrame(fullScreenIS);
    frame = showFullScreen(withCenteredButtons(jcenteredlabel("Lock mode!"),
      "Exit", rThread exitFullscreen);
    onFrameClose(frame, r { frame = null; });
  }
  
  void exitFullscreen enter {
    disposeFrame(frame);
  }
}