there is nothing helpful in those files you attached. And they are usind some .ui file which is not attached, and where all the gui is. Can you just attach your files? Files where you want to use that Tweet? For example what the item(int index) function come from?

I am learning the c++.
So learn it a little bit more on some simple examples and then try something more complex. Because we see you have a lack of basic C++ knowledge even with very simple C++ statements, so we can paste some working code for you but you will not understand major part of it! without a proper C++ knowledge...