2 subclasses of QSortFilterProxyModel behind each other.

[wysota]

Wysota, How do you think QIdentityProxyModel will address this?

It will call

sourceModel()->createIndex(index.row(), index.column(), index.internalPointer());

sourceModel()->createIndex(index.row(), index.column(), index.internalPointer());

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which will preserve:

• the model
• row and column
• implicitly the parent
• the internal pointer

Your implementation will only preserve row and column and maybe also the internal pointer. But certainly not the model (thus calling index.data(...) will return wrong values) and probably not the parent.

You should treat QIdentityProxyModel as a NO-OP, nothing more, nothing less.