When working with the FileMaker API for PHP there are a number of functions that are helpful when working with Value Lists. You can use the listValueLists function to return the names of any value lists associated with the layout you are referencing, and the getValueLists function to return a multi-level associative array of value lists (i.e. the contents of the value lists on the layout).
I noticed something strange today when working on a FileMaker v12 file hosted with FileMaker Server v12 – using these 2 functions I was seeing value lists that I was sure were not on the layout. After a bit of testing I found the source of the problem – some of the fields which were set to display as a simple “Edit box” had previously been set to display as a “Drop-down list”, and it was the value lists that were previously associated with these fields that were showing. Simply changing the field’s control style from “Drop-down list” to “Edit box” was not enough to remove it from the XML that is returned by the Web Publishing Engine – if you’ve used FileMaker Pro for a while you’ll have encountered this feature where FileMaker can “remember” previous settings for a field on a layout and when you switch it back from “Edit box” to “Drop-down list” it will remember the value list you had previously selected.
The only way to completely refresh the layout so that “remembered” value lists were not returned by the listValueLists and getValueLists functions was to remove the fields from the layout and manually add them again, ensuring that the control style was set to “Edit box” to start with (this is the default style when adding new fields to a layout).
I quickly checked a v11 solution running under FileMaker Server v11 and I wasn’t able to reproduce this issue, so it looks like a new issue with FileMaker Server v12 only. I’ll report it to FileMaker Inc in case it’s considered a bug, but it’s definitely a change from previous versions of FileMaker Server.