Androidx modules, android:attr/ttcIndex & android:attr/fontVariationSettings not found

Set your compileSdkVersion 'android-P' and targetSdkVersion 28

EDIT: Now compileSdkVersion 28 should also work meaning you no longer have to set it to android-P

Change compileSdkVersion as 'android-28' Change targetSdkVersion as '28'

If anyone else has stumbled upon this problem due to getting this error recently out of nowhere in your previously working fine react native projects - this is due to the latest BREAKING CHANGE in Google Play service and Firebase. Specially you will have problem with the packages which are dependent on -

com.google.android.gms:play-services-gcm

Check this thread first -

https://github.com/facebook/react-native/issues/25293

And solution would mostly be like this -

https://github.com/facebook/react-native/issues/25293#issuecomment-503045776