My app has windows that are components. In my case, now I have 2 components that have a drop down list that show the current logged user lists. So when I use one component for the first time it make a request to database, save data in model, and load data from model, but when the second component opens, it will just load data from model. Easy for now:
ListModel: this contains the current user lists.

Now I have another component but this needs the lists of another user. Where do I save these lists? I can't put in the ListModel as then will mix up with current user.

Just a remind: there is not just 2 users. It might have more users, so it should be scalable.

Then another problem that will solve both:
Each list has items. They will be saved in ListItemModel?
How to make to not mix between lists. So items from ListX doens't mix up with items from ListY?

thanks