bitrix.getNewsElementsTree.php

<?
defined("B_PROLOG_INCLUDED") && B_PROLOG_INCLUDED === true || die();
if (!Bitrix\Main\Loader::includeModule("iblock")) return;
/**
 * Когда нужно выводить элементы и получать из них разделы
 * @source: https://gist.github.com/geff21st/fbf0abeb5422678e4622ccc288a10dac
 * @global CMain $APPLICATION
 * @var array    $arParams
 * @var array    $arResult
 */


$arSections = [];
foreach ($arResult["ITEMS"] as &$arItem) {
	if ($sectID = $arItem["IBLOCK_SECTION_ID"]) {
		$arItem["SECTION"] = &$arSections[$sectID];
	}

	unset($arItem);
}
$arOrder = array("sort" => "asc", "date_active_from" => "desc");
$arFilter = array(
	"ACTIVE"    => "Y",
	"GLOBAL_ACTIVE" => "Y",
	"ID" => array_keys($arSections),
	"IBLOCK_ID" => $arResult["ID"],
);
$arSelect = array("ID", "IBLOCK_ID", "NAME");
$res = CIBlockSection::GetList($arOrder, $arFilter, false, $arSelect);
while ($sect = $res->GetNext()) {
	$arSections[$sect["ID"]] = $sect;
}
$arResult["SECTIONS"] = $arSections;

bitrix.getNewsSectionsTree.php

<?
defined("B_PROLOG_INCLUDED") && B_PROLOG_INCLUDED === true || die();
/**
 * Когда нужно выводить разделы, в которые вложены элементы
 * @source: https://gist.github.com/geff21st/fbf0abeb5422678e4622ccc288a10dac
 * @global CMain $APPLICATION
 * @var array    $arParams
 * @var array    $arResult
 */


if (!Bitrix\Main\Loader::includeModule("iblock")) return;

$arSections = [];

foreach ($arResult["ITEMS"] as $key => $arItem) {
	$sect = !empty($arItem["IBLOCK_SECTION_ID"]) ? $arItem["IBLOCK_SECTION_ID"] : "all";
	$arSections[$sect]["ITEMS"][$arItem["ID"]] = &$arResult["ITEMS"][$key];
}

$arNewSections = array();
$arOrder = array("sort" => "asc", "date_active_from" => "desc");
$arFilter = array(
	"ACTIVE"      => "Y",
	"ACTIVE_DATE" => "Y",
	"IBLOCK_ID"   => $arResult["ID"],
	"ID"          => array_keys($arSections),
);
$arSelect = array("ID", "IBLOCK_ID", "NAME");
$res = CIBlockSection::GetList($arOrder, $arFilter, false, $arSelect);
while ($sect = $res->GetNext()) {
	$arNewSections[$sect["ID"]]["SECT"] = $sect;
	$arNewSections[$sect["ID"]]["ITEMS"] = &$arSections[$sect["ID"]]["ITEMS"];
}

if (!empty($arSections["all"]["ITEMS"])) {
	$arSections["all"]["SECT"]["NAME"] = $arResult["NAME"];
	$arSections["all"]["SECT"]["ID"] = 0;
	array_unshift($arNewSections, $arSections["all"]);
}

//d($arSections, "sections");
//d($arResult, "items");
$arResult["SECTIONS"] = $arNewSections;

unset($arSections);