_getSource () {

        return this._source || this._getDefaultViewName();

    }
/**
     * Returns the source address for iframe element
     *
     * @returns {string}
     * @protected
     */
Returns the source address for iframe element
@returns {string}
@protected
Returns the source address for iframe element @returns { string } @protected
_getSource () {
        return this._source || this._getDefaultViewName();
    }
_getSource ( ) { return this . _source || this . _getDefaultViewName ( ) ; }
Returns the source address for iframe element
 @returns {string}
 @protected
Returns the source address for iframe element @returns { string } @protected