gtk:file-chooser-add-filter (chooser filter)

chooser -- a gtk:file-chooser widget
filter -- a gtk:file-filter object

Adds a file filter to the list of filters that the user can select between. When a file filter is selected, only files that are passed by that filter are displayed. The gtk:file-chooser implementation is deprecated since 4.10. Use the gtk:file-dialog object instead.