visible

Called without any parameters, the visible() method returns true if the ListBox is currently visible and false otherwise.
Calling it with a boolean true or false parameter will show and hide the ListBox widget.

<div id="listbox"></div>
<script type="text/javascript">
    $(function () {
        $("#listbox").shieldListBox({
            dataSource: {
                data: countries
            },
            textTemplate: "{name}",
            valueTempate: "{id}"
        });

        $("#listbox").swidget().visible(); // returns true
  
        $("#listbox").swidget().visible(false); // hides the widget
  
        $("#listbox").swidget().visible(); // returns false
    });
</script>