2. gtk.signal_list_item_factory.SignalListItemFactory.bind is emitted to bind the item passed
via gtk.list_item.ListItem.GObject.Object to the widgets that have been created in
step 1 or to add item-specific widgets. Signals are connected to listen to
changes - both to changes in the item to update the widgets or to changes
in the widgets to update the item. After this signal has been called, the
listitem may be shown in a list widget.
3. gtk.signal_list_item_factory.SignalListItemFactory.unbind is emitted to undo everything
done in step 2. Usually this means disconnecting signal handlers. Once this
signal has been called, the listitem will no longer be used in a list
widget.
Note that during the signal emissions, changing properties on the
listitems passed will not trigger notify signals as the listitem's
notifications are frozen. See gobject.object.ObjectG.freezeNotify for details.
gtk.signal_list_item_factory.SignalListItemFactory is a gtk.list_item_factory.ListItemFactory that emits signals to manage listitems.
Signals are emitted for every listitem in the same order:
1. gtk.signal_list_item_factory.SignalListItemFactory.setup is emitted to set up permanent things on the listitem. This usually means constructing the widgets used in the row and adding them to the listitem.
2. gtk.signal_list_item_factory.SignalListItemFactory.bind is emitted to bind the item passed via gtk.list_item.ListItem.GObject.Object to the widgets that have been created in step 1 or to add item-specific widgets. Signals are connected to listen to changes - both to changes in the item to update the widgets or to changes in the widgets to update the item. After this signal has been called, the listitem may be shown in a list widget.
3. gtk.signal_list_item_factory.SignalListItemFactory.unbind is emitted to undo everything done in step 2. Usually this means disconnecting signal handlers. Once this signal has been called, the listitem will no longer be used in a list widget.
4. gtk.signal_list_item_factory.SignalListItemFactory.bind and gtk.signal_list_item_factory.SignalListItemFactory.unbind may be emitted multiple times again to bind the listitem for use with new items. By reusing listitems, potentially costly setup can be avoided. However, it means code needs to make sure to properly clean up the listitem in step 3 so that no information from the previous use leaks into the next use.
5. gtk.signal_list_item_factory.SignalListItemFactory.teardown is emitted to allow undoing the effects of gtk.signal_list_item_factory.SignalListItemFactory.setup. After this signal was emitted on a listitem, the listitem will be destroyed and not be used again.
Note that during the signal emissions, changing properties on the listitems passed will not trigger notify signals as the listitem's notifications are frozen. See gobject.object.ObjectG.freezeNotify for details.
For tracking changes in other properties in the listitem, the ::notify signal is recommended. The signal can be connected in the gtk.signal_list_item_factory.SignalListItemFactory.setup signal and removed again during gtk.signal_list_item_factory.SignalListItemFactory.teardown.