I have question - how to use vidjet okteta::bytearrayrowview.

I have it in my designer, i have okteta and okteta-dev, but i can't compile project:

okteta/bytearrayrowview.h: No such file or directory

You need to ensure that Qt Creator is looking in the appropriate place for Okteta includes - and that your application is linking to the appropriate Okteta/Kasten libraries. In this case, those includes may be in a seperate package.

I imagined that it was. But I have no idea how to configure this.

All headers of okteta-dev package are in folders:
/ usr/include/okteta1
/ usr/include/kasten1
/ usr/include/KDE/okteta1
/ usr/include/KDE/kasten1

Assuming that you didn't add "#include <okteta/bytearrayrowview.h>" to anything yourself, I would suggest filing a bug at bugs.kde.org against Okteta.