Show/Hides toolbars.

def show_toolbars(self):
        """Show/Hides toolbars."""
        value = not self.toolbars_visible
        CONF.set('main', 'toolbars_visible', value)
        if value:
            self.save_visible_toolbars()
        else:
            self.get_visible_toolbars()

        for toolbar in self.visible_toolbars:
            toolbar.toggleViewAction().setChecked(value)
            toolbar.setVisible(value)

        self.toolbars_visible = value
        self._update_show_toolbars_action()