Everything is red and buggy. I don’t know what heppened there. I think there are some problems with Android Studio IDE. The XML still work normal but the Java code doesn’t.

Here is my code

I recently change the DNS setting from my PC to Google public DNS, I think it might be the problem but it’s unlikely.

I just created a new app to test and haven’t make any changes to the code. That code is from my 3rd attempt to create a new test project. I tried to add the dependency on androidx.appcompat:appcompat and import because it recomend it to me. However, after the gradle sync, nothing happends and the bugs is still there. I tried to reinstall Android Studio several times but it doesn’t work either.