pick events

def __onPickEvent(self, event=None):
        """pick events"""
        legline = event.artist
        trace = self.conf.legend_map.get(legline, None)
        visible = True
        if trace is not None and self.conf.hidewith_legend:
            line, legline, legtext = trace
            visible = not line.get_visible()
            line.set_visible(visible)
            if visible:
                legline.set_zorder(10.00)
                legline.set_alpha(1.00)
                legtext.set_zorder(10.00)
                legtext.set_alpha(1.00)
            else:
                legline.set_alpha(0.50)
                legtext.set_alpha(0.50)