I try to do something like this (original code was written in Python, so may be it has some syntax errors):
Qt Code: 
  1. QTreeView *tvGroups = new QTreeView()
  2. MyModel *groupModel = new MyModel()
  3. cb->setView(&tvGroups)
  4. cb->setModel(&groupModel)   
  5. cb->setModelColumn(0)
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cb is QComboBox.
After it usual integer combobox indexes become very strange.
In function which is connected to signal setCurrentIndex(int index) I print index and see that it has value -1 for items group2 and something_else, and 0 for others in the tree example below.
tree has such items:
Qt Code: 
  1. All 
  2.   group1
  3.     group1.1
  4.     group1.2
  5.   group2
  6.   something_else
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What is wrong?