Sets the filter that will be selected by default in the file chooser dialog.
If set to null, the first item in gtk.file_dialog.FileDialog.Gio.ListModel will be used as the default filter. If that list is empty, the dialog will be unfiltered.
a gtk.file_filter.FileFilter
Sets the filter that will be selected by default in the file chooser dialog.
If set to null, the first item in gtk.file_dialog.FileDialog.Gio.ListModel will be used as the default filter. If that list is empty, the dialog will be unfiltered.