How to use property handlers.

property-handler-definition.php

<?php namespace Acme\Foo\Form;

use Anomaly\Streams\Platform\Ui\Form\FormBuilder;

class FooFormBuilder extends FormBuilder
{

        /**
         * Define your property normally.
         */
        protected $sections = [
                // Your sections information.
        ];

        /**
         * You can define your own handlers.
         */
        protected $sections = 'My\Section\HandlerClass@handle';
        
        /**
         * Or use use the default handler.
         */
        // protected $sections = [];
        // Will look for 'Acme\Foo\Form\FooFormSections@handle' if no $sections are defined and default to [] or null usually;
        
}