QTreeView details: what are viewItems?

[ChrisW67]

Within the Qt source the private implementation is usually in a file named blah_p.h for a class blah with its public API in blah.h. The private header is #included into the implementation file blah.cpp but not inthe public header or user programs.

I would not worry too much about the internals of the views and models if all you want to do is use them.