Quote Originally Posted by wysota View Post
You need to know how much data you expect to receive in total. Then when reading the data, calculate how much you already received and set those values on a progress bar.


Use something smarter than QDataStream. This is a really lame approach in terms of efficiency.
Yes, theoretically I understand how I need to calculate, but my question was how!? May be some signals?
I'm afraid I have to use QDataStream because I need to transfer complicated data structure (QList) via socket, and for this small app no reason to make my own functions.
I think the speed issue did not correlate with QDataStream, my be with some settings, memory pre-allocation but not with QDataStream itself.