TreeView with functionality to go back and forth flat list and hierarchical view?
I am looking for the best approach or recommended approach to implementing a tree view which can display as a flat list as well as hierarchical view via a toggle button.
The target widget taking the model is a QTreeView. I already have a tree model class that implements QAbstractItemModel and the hierarchical aspect is all sorted. What I need now is a way for the same tree view to display the items as a flat list. I can either create a brand new model and pass that to the tree view or write a class implementing a QAbstractProxyModel and pass that to the tree view instead. I am attempting option 2. I was looking at deriving QIdentityProxyModel with a flag in my derived class that determines if I should do some other logic if displaying as a flat list or forward calls (e.g. mapFromSource, mapToSource, etc) to the QIdentityProxyModel if displaying as a hierarchy.
Does this sound like a sensible approach? I had a go at this and it seems Qt is still passing me old proxy indices created by QIdentityProxyModel even when the view is in the flat list model. Is there something I need to do to force the UI to refresh so it would call index() to generate the new proxy index for each item?
What about having two views on your model rather that trying to fit everything in a tree view ?
You can then use a QStackedLayout and switch between the views.
I think you are describing exactly the functionality of KDescendantsProxyModel