Cannot resolve symbol 'Theme' in styles.xml (Android Studio)

Question

Since today, Android Studio can\'t find the AppCompat themes in styles.xml, but for example AppCompatActivity in code does get recognized. My Android Studio version

Answer 1

@Daniel Wilson made a comment in one of the answers that solved this issue for me. I wanted to add add as an answer to draw more attention to this solution.

Updating compileSdkVersion and targetSdkVersion from 26 to 27 (and then of course updating the dependencies) eliminated the errors for me.