Variables with underline

Question

I\'m getting an underline in some variables on Android Studio (in this case on the \'position\' variable). I think it\'s not an error because the application runs perfectly

Answer 1

It may be because a immutable variable is subjected to modification. Like reassigning a String or trying to modify a final declared variable.

String buffer = "";
buffer = buffer + "new string";

Will underline the buffer, since string are of immutable Objects.