Can I add GtkEntryCompletion to GtkEntry in Glade?
I seem to be able to create the GtkEntryCompletion in general, but I can't figure out if it's possible to tell to GtkEntry "this is your completion object" (in Glade GUI).
Select the GtkEntry, then go into the Properties window and switch to the General tab. Near the top you should see an entry that says "Completion" with an icon on the right of it. Click that icon, and the Objects window should pop up, letting you choose the GtkEntryCompletion you created.