Automatic filters not showing up

When I add
mygrid.attachHeader("#text_filter",…);

boxes show up below the header that say “#text_filter”.

What else do I need to add to insert these automatic filters as discussed on:
docs.dhtmlx.com/doku.php?id=dhtm … ra#filters

You should add dhtmlxgrid_filter.js file to your page

You can find working example here dhtmlx.com/docs/products/dht … _srnd.html