How do I add a list to a dropdown box using the file chooser

Hello,

I'm looking at how I can load a list from an external .txt file and add it to the contents of a dropdown box.

I'm assuming i can use the File Chooser plugin, load the text file and then use the 'add item' action to add the list to the dropdown box?

If anyone could guide me on how best to go about it I'd really appreciate it!

Many thanks...