/**
  * Renders a text area.
  * The model attribute value will be used as the content in the textarea.
  * @param array $options the tag options in terms of name-value pairs. These will be rendered as
  * the attributes of the resulting tag. The values will be HTML-encoded using [[Html::encode()]].
  *
  * If you set a custom `id` for the textarea element, you may need to adjust the [[$selectors]] accordingly.
  *
  * @return $this the field object itself
  */
 public function textarea($options = [])
 {
     $options = array_merge($this->inputOptions, $options);
     $this->adjustLabelFor($options);
     $options['ng-model-options'] = $this->getNgModelOptions();
     $this->parts['{input}'] = Html::activeTextarea($this->model, $this->attribute, $options);
     return $this;
 }