QTreeView and RootIndex

[Qiieha]

Hi guys,
i have a problem. I use a QTreeView and with a subclass of QAbstractItemModel.
It works.
A
..B
..C
....D
For filter reasons I change the root index via setRootIndex.

setRootIndex(B);

setRootIndex(B);

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It works, but after setting the root index, the rootIndex is not shown. (rootIsDecorated is true.)
C
....D

Furthermore I'm not able to unset the filter, because my A node never gets back.

setRootIndex(A); // A is model.index(0,0);

setRootIndex(A); // A is model.index(0,0);

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What can I do?
thanks

[wysota]

Root index is never shown. The view always shows children of the root index.

[Qiieha]

Thank you wysota!
If I don't set the rootIndex initially, the root index is shown.

greets

[wysota]

Because it is set to an invalid index (QModelIndex()) which happens to point to the top of the model.