provider view model with collection of objects - flutter

Question

I have a state model that has collection of objects that have a collection of objects inside as well (think collection of todo lists):
class StateModel extends ChangeNotifier {
List<TodoList> todoLists;
}
simplified TodoList class looks like this:
class TodoList {
int id;
List<Item> items;
}
class Item {
int id;
String name;
bool status; // true is done, false is not done
}
Now one of my Views is ListView of my todo lists (where I display only name) and that's east. But I want to have a todo list detail view (where data of single todo list is displayed) where I want to mark todo items as done (i.e. set their status to true). How should I do it? I could have method in StateModel which would find a TodoList object by id, then mark items as done. This could look something like this:
class StateModel extends ChangeNotifier {
// (...)
void markItemAsDone(listId, itemId) {
// find todo list in StateModel
// find item in given list
// mark it as done
// notifyListeners()
}
}
But this seems wrong. What I would like to have is a way to get TodoList object view model and use its methods, not StateModel methods. How should I approach this? Can I have another view model (TodoListState), and have a collection of TodoListState objects in StateModel? Is this a use case for ProxyProvider?
I hope my question is clear, let me know if this needs more explanation.

Answer 1

My way is when you the pop back from the detail view, you also transfer a value:
I await for the value from the pop back then you do something with the value. Here is my code
#override
Widget build(BuildContext context) {
WordModel provider = Provider.of<WordModel>(context);
return Consumer<WordModel>(
builder: (BuildContext context, value, Widget child) => InkWell(
onTap: () async {
dynamic status = await Navigator.of(context).push(PageRouteBuilder<ListFavouriteWord>(
pageBuilder: (BuildContext context, Animation<double> animation,
Animation<double> secondaryAnimation) {
return ListFavouriteWord(value);
}));
//do something with markedValue
//provider.update(status)
},
child: Padding(
padding: const EdgeInsets.only(top: 16.0, right: 16.0),
child: Badge(
child: Icon(Icons.face),
badgeContent: Text(
"${value.counter}",
style: Theme.of(context)
.textTheme
.button
.copyWith(color: Colors.white, fontSize: 10.0),
),
),
),
),
);
}
I have found another way to do it. You just need:
ChangeNotifierProvider.value() to use your provider in your previous route
My code:
onTap: () async {
dynamic markedValue = await Navigator.of(context).push(
PageRouteBuilder<ListFavouriteWord>(
pageBuilder: (BuildContext context, Animation<double> animation,
Animation<double> secondaryAnimation) {
return ChangeNotifierProvider.value(
value: value,
child: ListFavouriteWord(),
);
}));
}