Filter multiple different main queries on custom pages

Question

Ok so I have multiple different page templates with a main query that I want to filter the loop for. In my example I try to use a function to filter the main loop of my site and also the main loop for the page 'new'. Now this works fine for the main page but makes the 'new' page return a 'page not found' not taking the custom template that's assigned to it. What's the right way to do this?

function fod_filter_main_query( $query ) {

    if( is_front_page() && is_main_query() ) {


        $query->set('meta_key', 'hotness');
        $query->set('meta_value', 0 );
        $query->set('meta_compare', '>');
        $query->set('orderby', 'meta_value_num' );
        $query->set('order', 'desc');
        $query->set('cat', -1 );
        $query->set('posts_per_page', 16 );
        $query->set('post_type', array( 'post','fod_videos','fod_music','fod_articles', 'fod_albums'  ));

    } elseif  ( is_page('new') && is_main_query() ) {

        $query->set('cat', -1 );
        $query->set('order', 'asc');
        $query->set('posts_per_page', 16 );
        $query->set('post_type', array( 'post','fod_videos','fod_music','fod_articles', 'fod_albums'  ));

    }

}
add_action('pre_get_posts', 'fod_filter_main_query', 9999);

Answer 1

You can't alter a page query via pre_get_posts (in any fashion I've tried) to something other than a page query. If you look at the generated SQL, it's trying to query all your post types for a pagename of new. If you set pagename to null, it'll return posts, but it will disregard any taxonomy parameters you try to set.

Even if you could successfully alter the query, it would no longer be a page and wouldn't load a page template.

I think the simplest way to handle this is to just create a new query in your template via WP_Query.