basefilter.php

См. документацию.

<?php
namespace Bitrix\UI\EntitySelector;
 
abstract class BaseFilter
{
    protected $options = [];
 
    protected function __construct()
    {
        // You have to validate $options in a derived class constructor
    }
 
    abstract public function isAvailable(): bool;

    abstract public function apply(array $items, Dialog $dialog): void;
 
    public function getOptions(): array
    {
        return $this->options;
    }
 
    public function getOption(string $option, $defaultValue = null)
    {
        return array_key_exists($option, $this->options) ? $this->options[$option] : $defaultValue;
    }
}