Extending Gtk::EntryCompletion

The default behaviour when using GtkEntryCompletion together with GtkEntry is for the auto-completion popup to appear only for the first entered string, replacing the entry’s content on item selection. But for Paperbox I wanted to have auto-completion in a Gtk::Entry which allows multiple words to be auto-completed. Turns out that this is very easy to implement, you just need to write a custom matching function which does not always compare against the whole entry text but also looks for whitespace and previous words, and override Gtk::EntryCompletion::on_match_selected() to append new text at the end of an entry’s content. The EntryMultiCompletion class is now in gtkmm-utils git tree.