public void SwitchScreen(GameScreen alternate1, GameScreen alternate2) {
Logger.Log ("GuiTransitioner::SwitchScreen("+alternate1+","+alternate2+")");
if (_currentScreen == alternate1) {
GoToScreen(alternate2);
} else if (_currentScreen == alternate2) {
GoToScreen(alternate1);
} else {
Logger.Log ("GuiTransitioner::SwitchScreen("+alternate1+","+alternate2+"): error: unmanaged alternate", Logger.Level.WARN);
}
}