Is the provider +change notifier app really just lifting state up?

Hi, all great resource!

Little confused by this page
https://github.com/brianegan/flutter_architecture_samples/blob/master/change_notifier_provider/lib/edit_todo_screen.dart

It appears to be updating and passing changes back using a callback rather than provider. Any reason for this?

` widget.onEdit(_taskController.text, _noteController.text);`

Start with change_notifier_provider/lib/edit_todo_screen.dart and the callback invocation shown in the issue. Compare that usage with the surrounding provider example, then clarify why the callback is used or identify the documentation or sample explanation that needs updating; the issue is done when that question has an explicit answer.

Written by the indexing model from the issue text.