<p>Both are rude. At the very least don’t text in class unless you are in a huge lecture hall and there’s no way your professor can see you, and even then keep it to a minimum because it’s rude to the people around you. Most people will wear hats in class still but it is in poor taste.</p>
<p>“One of the ways your professor figures out whether he’s explained something well enough is to look at faces. Your face is harder to see when you are wearing a hat with a brim.”</p>
<p>This is also a very good point. I have had professors specifically complain about that.</p>