selectValueDidChange (evt) {
    // notify model
    let index = parseInt(this._$select.value)
    let value = this.getModel().getElementAt(index)
    this.getModel().viewValueDidChange(this, value)
  }
/**
   * Triggered when select value has been changed.
   * @param {Event} evt
   */
Triggered when select value has been changed.
@param {Event} evt
Triggered when select value has been changed . @param { Event } evt
selectValueDidChange (evt) {
    let index = parseInt(this._$select.value)
    let value = this.getModel().getElementAt(index)
    this.getModel().viewValueDidChange(this, value)
  }
selectValueDidChange ( evt ) { let index = parseInt ( this . _$select . value ) let value = this . getModel ( ) . getElementAt ( index ) this . getModel ( ) . viewValueDidChange ( this , value ) }
Triggered when select value has been changed.
Triggered when select value has been changed .
// notify model