'Auto fade out the Bubble'

def hide(self, now=False):

    def on_stop(*l):
        if self.modal:
            m = self._modal_view
            m.remove_widget(self)
            Window.remove_widget(m)
        Window.remove_widget(self)
        if self.exit:
            App.get_running_app().stop()
            import sys
            sys.exit()
        else:
            App.get_running_app().is_exit = False
    if now:
        return on_stop()
    anim = Factory.Animation(opacity=0, d=0.25)
    anim.bind(on_complete=on_stop)
    anim.cancel_all(self)
    anim.start(self)
