how to sort a multi dimensional model
===

I'm using PySide to write a plugin browser. The available plugins are stored in a three dimensional model like this:

    pluginType/pluginCategory/pluginName

e.g.:

    python/categoryA/toolA
    python/categoryB/toolAA

etc.

In my custom view, I am showing all tools of a given plugin type (i.e. "python") in a list, regardless of their category:

    (python)
    categoryA/toolA
    categoryA/toolB
    categoryA/toolC
    categoryB/toolAA
    categoryB/toolBB
    categoryB/toolCC
   

I am now wondering how to best sort this view, so the tools are sorted by name regardless of their parent category. The sorting method in my current proxy model yields a sorted list per category like the above one, but what I am after is this:

    (python)
    categoryA/toolA
    categoryB/toolAA
    categoryA/toolB
    categoryB/toolBB
    categoryA/toolC
    categoryB/toolCC


Do I have to make my proxy model convert the multi-dimensional source model into a one-dimensional one in order to achieve this or is there a better way? I would love to be able to sync the custom view with a standard tree view which is why I chose the multi-dimensional model.

Thanks,
frank