Why is the `if else` not working?

Question

I have this on my header.php.

It checks whether the page is on homepage/frontpage, is on category/children of/has the category of "gamenews", or is on category/children of/has the category of "hobbynews".

Basically, if it's on homepage/frontpage, it outputs nothing.

On the other hand, if it's on gamenews, it outputs something. If it's on hobbynews, it outputs another thing. You could see in details below. I'm using a custom function there (is_category_or_sub).

        <?php if ( is_home() || is_front_page() ) { ?>

        <?php } elseif ( is_category_or_sub('gamenews') || has_category('gamenews') ) { ?>
        <ul id="sections">
            <?php $category = get_category_by_slug( 'gamenews' );
            wp_list_categories(array(
                  'child_of' => $category->term_id,
                  'title_li' => '',
                  'hide_empty' => 0,
                  'orderby' => 'count',
                  'walker' => new WPSE67791_Walker_Category
               )); ?>
        </ul><!-- #sections -->

        <?php } elseif ( is_category_or_sub('hobbynews') || has_category('hobbynews') ) { ?>
        <ul id="sections">
            <?php $category = get_category_by_slug( 'hobbynews' );
            wp_list_categories(array(
                  'child_of' => $category->term_id,
                  'title_li' => '',
                  'hide_empty' => 0,
                  'orderby' => 'count',
                  'walker' => new WPSE67791_Walker_Category
               )); ?>
        </ul><!-- #sections -->
        <?php } ?>

Now the first check (is_home/is_frontpage) works just fine. So does the second (the one on "gamenews").

However, the last one ("hobbynews") doesn't work.

Each time I visit page which has that requirement (is on category/children of/has the category of "hobbynews"), it displays stuff which is supposed to be on gamenews. The one I want to display on hobbynews does not show up.

Why is this happening? I've been trying to re-order, tried to use nested if, etc. But it's still not working and really confusing...

---

EDIT:

This is my is_category_or_sub, located on functions.php:

function is_category_or_sub( $cat_slug = get_category_by_slug ) {
    foreach (get_the_category() as $cat) {
        if ($cat_slug || cat_is_ancestor_of($cat_slug->term_id, $cat)) return true;
    }
    return false;
}

Answer 1

Assuming you're using the function is_category_or_sub() as given on http://valendesigns.com/wordpress/is-category-or-subcategory-wp-function/

That function takes category id as the argument, not the slug. The string "gamenews" here when type-casted to an integer becomes 0 which is an ancestor for every other category. Can you try changing the function code to this-

// If is category or subcategory of $cat
if (!function_exists('is_category_or_sub')) {
    function is_category_or_sub($cat = 0) {
            if(is_numeric($cat)) {
                $cat_id = $cat;
            } elseif(is_string($cat)) {
                $cat = get_term_by('slug', $cat, 'category');
                $cat_id = $cat->term_id;
            } else {
                return false; // neither id nor slug
            }
            foreach (get_the_category() as $cat) {
                if ($cat_id == $cat->cat_ID || cat_is_ancestor_of($cat_id, $cat)) return true;
            }
            return false;
    }
}

This function now supports both id & slug