BaseReport::getGroupingField

public function getGroupingField(DropDown $whatWillCalculateField)
{
	$groupingField = new CustomDropDown('groupingBy');
	$groupingField->setLabel(Loc::getMessage('BASE_REPORT_HANDLER_GROUPING'));
	$groupingField->addOptions($this->getGroupByOptions());
	$whatWillCalculateField->addJsEventListener($groupingField, $groupingField::JS_EVENT_ON_CHANGE, array(
		'class' => 'BX.Report.VisualConstructor.FieldEventHandlers.WhatWillCalculate',
		'action' => 'reloadCompatibleCalculatedTypes',
	));
	$whatWillCalculateField->addAssets(array(
		'js' => array('/bitrix/js/report/js/visualconstructor/fields/whatwillcalculate.js')
	));

	return $groupingField;
}