Is it ok for a

[RudolfVonKrugstein]

Let's assume I have an AppState like this:

class ListItem {
    final String stuff;
    final int moreStuff;
}

class AppState {
    final List<ListItem> items;
}

Now I want to write a widget, that displays a single ListItem:

class _ViewModel {
    _ViewModel fromStore(...) { 
        // How do I get the ListItem to derive data from?
    }
}

class ListItemWidget extends StatelessWidget {
    ListItemWidget(ListItem listItem);
    final ListItem listItem;
    @override
    Widget build(BuildContext context) {
        return StoreConnector<AppState>(
            mode: _ViewModel
            child: ListTile(/*Stuff based on an instance of ListItem */);
        );
    }
}

Now the problem is: The _ViewModel must be created with a particular ListItem, and just passing the store to it (in fromStore) is not enough because I would not know which ListItem to use. I could write a converter and a second factory function to create the _ViewModel. In that case, I could pass the ListItem to the converter and the factory function. But it seems kind of hacky to me, because I am ignoring the fromStore constructor.

How would you do this?

[marcglasberg]

I'm not sure your question makes sense. If your ListItemWidget accepts a ListItem in its constructor, then you don't need any info from the store anymore. Just do this:

class ListItemWidget extends StatelessWidget {
    ListItemWidget(ListItem listItem);
    final ListItem listItem; 
   @override
    Widget build(BuildContext context) =>ListTile(listItem); 
}

If you are trying to display list items from their indexes, then you could read them from the store, like this:

class ListTileConnector extends StatelessWidget {
    ListItemWidget(int index);
    final int index;
    @override
    Widget build(BuildContext context) {
        return StoreConnector<AppState>(
            converter: ViewModel.from(store, index),
            child: ListTile(vm.listItem);
        );
    }
}

class ViewModel {
   ListItem listItem;

   ViewMode(this.listItem);

    ViewModel from(Store store, int index) { 
        return  ViewModel(store.items[index]) 
    }

   // Don't forget to add equals/hashcode here.
}

Or maybe you just want to read the whole list from the store at once, like this:

class ListOfAllItemsConnector extends StatelessWidget {
    @override
    Widget build(BuildContext context) {
        return StoreConnector<AppState>(
            converter: ViewModel.from(store),
            child: ListOfAllItems(vm.list);
        );
    }
}

class ViewModel {
   List<ListItem> list;

   ViewMode(this.list);

    ViewModel from(Store store) { 
        return  ViewModel(store.items) 
    }

   // Don't forget to add equals/hashcode here.
}