I have an issue with this project, I\'m trying to build it after updating Android Studio to the 3.1 version, also I have updated gradle to the version 3.1.0, just the gradle Syn
I've encountered the same problem and this is the solution that fixed my problem.
I used findViewById
for each view defined in the layout file to get a reference from the XML.
But in Android Studio 3.1 I no longer have to use this.
I simply removed all of the findViewById
code where I placed to get the reference from the XML layout and now the error is gone!