/**
* Renders a list of checkboxes.
* A checkbox list allows multiple selection, like [[listBox()]].
* As a result, the corresponding submitted value is an array.
* The selection of the checkbox list is taken from the value of the model attribute.
* @param array $items the data item used to generate the checkboxes.
* The array values are the labels, while the array keys are the corresponding checkbox values.
* Note that the labels will NOT be HTML-encoded, while the values will.
* @param array $options options (name => config) for the checkbox list. The following options are specially handled:
*
* - unselect: string, the value that should be submitted when none of the checkboxes is selected.
* By setting this option, a hidden input will be generated.
* - separator: string, the HTML code that separates items.
* - item: callable, a callback that can be used to customize the generation of the HTML code
* corresponding to a single item in $items. The signature of this callback must be:
*
* ~~~
* function ($index, $label, $name, $checked, $value)
* ~~~
*
* where $index is the zero-based index of the checkbox in the whole list; $label
* is the label for the checkbox; and $name, $value and $checked represent the name,
* value and the checked status of the checkbox input.
* @return static the field object itself
*/
public function checkboxList($items, $options = [])
{
$this->adjustLabelFor($options);
$this->parts['{input}'] = Html::activeCheckboxList($this->model, $this->attribute, $items, $options);
return $this;
}
