def init_widget(self):
        """ Initialize the underlying widget.

        """
        super(AndroidSwipeRefreshLayout, self).init_widget()
        d = self.declaration
        w = self.widget
        if not d.enabled:
            self.set_enabled(d.enabled)
        if d.indicator_background_color:
            self.set_indicator_background_color(d.indicator_background_color)
        if d.indicator_color:
            self.set_indicator_color(d.indicator_color)
        if d.trigger_distance:
            self.set_trigger_distance(d.trigger_distance)
        w.onRefresh.connect(self.on_refresh)
        w.setOnRefreshListener(w.getId())
Initialize the underlying widget.