Why is the code section highlighted?

Question

Android

The people, perhaps a stupid question, but I didn’t just encounter a problem, but an unpleasant situation, so to speak, the program listing is highlighted and catches my eye and I can’t understand what the problem could be, I understand that IDEA doesn’t like something, but What could it be? The hint asked me to press the key combination alt + f1, but this does not tell me anything. The funny thing is that everything works, it seems to be even correct, but this is not accurate.

Answer 1

The studio tells you that instead of the argument OnCompleteListener < Void > () you send OnCompleteListener (). There is a type cast without checking if it is possible.