Source: widgets/ButtonOptionWidget.js

/**
 * ButtonOptionWidget is a special type of {@link OO.ui.mixin.ButtonElement button element} that
 * can be selected and configured with data. The class is
 * used with OO.ui.ButtonSelectWidget to create a selection of button options. Please see the
 * [OOjs UI documentation on MediaWiki] [1] for more information.
 *
 * [1]: https://www.mediawiki.org/wiki/OOjs_UI/Widgets/Selects_and_Options#Button_selects_and_options
 *
 * @class
 * @extends OO.ui.OptionWidget
 * @mixes OO.ui.mixin.ButtonElement
 * @mixes OO.ui.mixin.IconElement
 * @mixes OO.ui.mixin.IndicatorElement
 * @mixes OO.ui.mixin.TitledElement
 *
 * @constructor
 * @param {Object} [config] Configuration options
 */
OO.ui.ButtonOptionWidget = function OoUiButtonOptionWidget( config ) {
	// Configuration initialization
	config = config || {};

	// Parent constructor
	OO.ui.ButtonOptionWidget.parent.call( this, config );

	// Mixin constructors
	OO.ui.mixin.ButtonElement.call( this, config );
	OO.ui.mixin.IconElement.call( this, config );
	OO.ui.mixin.IndicatorElement.call( this, config );
	OO.ui.mixin.TitledElement.call( this, $.extend( {}, config, { $titled: this.$button } ) );

	// Initialization
	this.$element.addClass( 'oo-ui-buttonOptionWidget' );
	this.$button.append( this.$icon, this.$label, this.$indicator );
	this.$element.append( this.$button );
};

/* Setup */

OO.inheritClass( OO.ui.ButtonOptionWidget, OO.ui.OptionWidget );
OO.mixinClass( OO.ui.ButtonOptionWidget, OO.ui.mixin.ButtonElement );
OO.mixinClass( OO.ui.ButtonOptionWidget, OO.ui.mixin.IconElement );
OO.mixinClass( OO.ui.ButtonOptionWidget, OO.ui.mixin.IndicatorElement );
OO.mixinClass( OO.ui.ButtonOptionWidget, OO.ui.mixin.TitledElement );

/* Static Properties */

/**
 * Allow button mouse down events to pass through so they can be handled by the parent select widget
 *
 * @static
 * @inheritdoc
 */
OO.ui.ButtonOptionWidget.static.cancelButtonMouseDownEvents = false;

/**
 * @static
 * @inheritdoc
 */
OO.ui.ButtonOptionWidget.static.highlightable = false;

/* Methods */

/**
 * @inheritdoc
 */
OO.ui.ButtonOptionWidget.prototype.setSelected = function ( state ) {
	OO.ui.ButtonOptionWidget.parent.prototype.setSelected.call( this, state );

	if ( this.constructor.static.selectable ) {
		this.setActive( state );
	}

	return this;
};