QTreeView Class Reference
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setModel (self, QAbstractItemModel model)

QAbstractItemView.setModel (self, QAbstractItemModel model)

Sets the model for the view to present.

This function will create and set a new selection model, replacing any model that was previously set with setSelectionModel(). However, the old selection model will not be deleted as it may be shared between several views. We recommend that you delete the old selection model if it is no longer required. This is done with the following code:
 QItemSelectionModel *m = view->selectionModel();
 view->setModel(new model);
 delete m;



QTreeView.setRowHidden 
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これで一時的に隠すような考え方ができないか？？