php - WP-Query / pre_get_posts / category / not working

Question

I am trying to get only results of the WordPress main-category without any child-categories/sub-categories. Any advice on how to achieve this?

This code is not working:

$cat_slug = $_POST['v1'];

function cat_query_filter($query) {
  
    if(!is_admin()) {

        $idObj = get_category_by_slug($cat_slug);
        $cat_id = $idObj->term_id;
        $query->set('category__in', $cat_id );

        };
}

add_action('pre_get_posts', 'cat_query_filter');

question from:https://stackoverflow.com/questions/66061737/wp-query-pre-get-posts-category-not-working

Answer 1

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