code: protected function renderInput($options = [], $resultsOptions = [])
      {
          Html::addCssClass($options, 'prompt');
  
          $lines = [];
          $input = $this->hasModel()
              ? Html::activeTextInput($this->model, $this->attribute, $options)
              : Html::textInput($this->name, $this->value, $options);
  
          if (!empty($this->displayIcon)) {
              $lines[] = Html::beginTag('div', ['class' => 'ui icon input']);
              $lines[] = $input;
              $lines[] = Html::tag('i', '', ['class' => 'icon search']);
              $lines[] = Html::endTag('div');
          } else {
              $lines[] = $input;
          }
          $lines[] = Html::tag('div', '', $resultsOptions);
          return implode("\n", $lines);
      }
docs: Generates the search input
  
  @param array $options the tag options in terms of name-value pairs
  @param array $resultsOptions the results layer options in terms of name-value pairs
  
  @return string the generated search input