[Interest] QML ListModel of ListModels?

[Jason H]

In a flickable, I want to have a 2-layer hierarchy:
Category 1
  Item 1
  Item 2
Category 2
  Item 1
  Item 2
...
Category N
  Item X
  Item Y
  Item Z
 

How can I create QML element that allows any number of Categories and Items? Can I use one root model?
Or must I create these categories dynamically using createComponent? I'd rather not use createComponent.

Thanks.