paint QTreeView item !!

[mcenatie]

I create a QTreeView and I set my custom model and my custom delegate. In my delegate I redefine the paint method to paint the items of the QTreeView like I want. The issue is that the branches are not paint (I have attached a picture of the QTreeView).
So how can I do to paint the item and the branch using my delegate ? I'd like to avoid to subclass QTreeView and redefine the drawBranches method ....
Thanks for your help!