enabled

The enabled() method, called without any parameters, will return the current enabled state of a SplitButton element.
The enabled(bool) method is used to update a SplitButton's enabled/disabled state. Passing true will enable and false will disable the element.

<button id="but1">Split Button</button>

<script type="text/javascript">
     $(function () {
        $("#but1").shieldSplitButton({
        });
    });

    $("#but1").swidget().enabled(); // return true
    
    $("#but1").swidget().enabled(false) // disable the button
    
    $("#but1").swidget().enabled(); // return false
</script>