Finishes the gtk.alert_dialog.AlertDialog.choose call and returns the index of the button that was clicked.
a gio.async_result.AsyncResult
the index of the button that was clicked, or -1 if the dialog was cancelled and propertyGtk.AlertDialog:cancel-button is not set
Finishes the gtk.alert_dialog.AlertDialog.choose call and returns the index of the button that was clicked.