Hello, guys!

I need to do a simple task, but i'm somehow lost about how to do it
Need a little help.

What I need is the following:
I have a QTreeView with 3 columns. And I want to set its header so the:
1st column has predefined size (calculated once by me)
2nd column is stretches to fit all available size
3rd column has predefined size as well.

I.e. in <b>constructor</b> I want to set two sizes that I calculate and have the middle field to be resized so it stretches to all available size.
And I want all columns to stay resizable by user, so setResizeMode( ResizeToContents ) or whatever is not an option.

How to do that? Tried many ways with no luck. I'm lost