Studio is the development of the app, but not the running app it self.
So in Studio you add a list, connects it with an entity (database table) define the attributes of the entity you want to show in the list.
In your case you want to show a list of Groceries. Thus you need an entity Grocery, with attributes like name, price, unit?
In the listview you set the entity Grocery as data source, in the list you connect the text widgets with the attribute name, price and unit.
In the running app you will see in the first row the first record(object), the second row the second etc.
In development (Studio) you only see the connected attributes
Suggestion; take the rapid developer learning path to understand more of pages, entities, domain model etc
This is how it turned out. Now it works. :)