vendor/uui/js/u-ui.js
function () {
        if (this._btnElement.checked) {
            u.addClass(this.element, this._CssClasses.IS_CHECKED);
        } else {
            u.removeClass(this.element, this._CssClasses.IS_CHECKED);
        }
    }
function () {
        if (this._btnElement.checked) {
            u.addClass(this.element, this._CssClasses.IS_CHECKED);
        } else {
            u.removeClass(this.element, this._CssClasses.IS_CHECKED);
        }
    }
function ( ) { if ( this . _btnElement . checked ) { u . addClass ( this . element , this . _CssClasses . IS_CHECKED ) ; } else { u . removeClass ( this . element , this . _CssClasses . IS_CHECKED ) ; } }
Check the components toggled state.

@public
Check the components toggled state .