Hi Leo,

Yes, the original post is probably a typo. I extracted that code from a more complex template, and probably forgot to remove one of the </tpl> tags.

My earlier post was assuming you were using Ext3. In Ext3, LabKey overrode the default Ext combo to add a few behaviors. Primarily, this involved the ability of the list to automatically resize itself based on the width of the items, and there are options surrounding blank records. These include the ability to set a custom caption (ie. nullCaption), and the ability to have the combo automatically add a blank record to the store if no record was present. These are not really part of our public API and probably not included with those docs.

In Ext4, I think we will do things a little differently. In Ext4, more of these options are built into the combo, or available with pretty good UX components. Therefore there is less need to create a labkey-specific component. For your work, understanding how Ext Xtemplates work can be really helpful, and I'd encourage you to take a look at the example above and be sure you understand what it's trying to do. Ext's docs are pretty good for them as well. Many extensions of fields can be handled cleanest by customizing the field tpl.