Show list of entries from specific category while showing a detail

Question

i'm creating a portfolio site where artists can show projects. artists are a category

on a project page (from an artist) i want to show the artists other projects as well. this seems simple but i'm not sure how to do this:

// get the category_id   
    {exp:channel:entries channel="projects" status="open" limit="1" orderby="entry_date" sort="asc"}
        {categories show_group="1"}
           // parents from the categories are not artists but artist groups
            {if category_id != "1" AND category_id != "2" AND category_id != "3" AND category_id != "4"}
                <?php $artistid="{category_id}"; ?>
            {/if}
        {/categories}
    {/exp:channel:entries}

// show all titles from the category id (artist id)
    {exp:channel:entries channel="projects" category="<?php echo $artistid ?>" status="open" limit="50" orderby="entry_date" sort="asc" dynamic="off"}
         {title} /
    {/exp:channel:entries}

eg on portfolio/project/test-dave-eerste-van-de-dag, the artist_id is 6 but it doesn't work in the second exp:channel:entries. php is on output. probably it goes wrong with both input and output. there must be an easier way to do this!

Answer 1

I would try using an embed to pass through your php variable. So the first half stays the same then:

// show all titles from the category id (artist id)
    {embed="template_group/template_name" cat_id="<?php echo $artistid ?>"}

Then in your embedded template

{exp:channel:entries channel="projects" category="{embed:cat_id}" status="open" limit="50" orderby="entry_date" sort="asc" dynamic="off"}
         {title} /
    {/exp:channel:entries}