Clip part of the viewport in place

[rknall]

Hello

I am currently trying to implement a "Fixed Column" widget (think fixed columns in Excel) for an open-source project. I started with the example from Qt, but that was based on a QTableView and we need a QTreeView widget.

One of the remaining issues I am having is, that the header is not set in place.

As you can see, the two columns for Time and Destination are off, when scrolling sideways. This is what it looks when no scrolling had occured:

I had some ideas, but none of those seemed to work. My latest is to fix either the viewport and prevent an update, or to implement a second header and stick that.

Anyone got a better idea? I can gladly share the code if you like (or you can take a look at https://code.wireshark.org/review/c/34410 which contains the latest version.

Any help would be greatly appreciated

kind regards
Roland