title: Android Studio findViewById(R.id.button1) error
body: <p>Having findViewById(R.id.button1) gives me an error. It was telling me to change the code to findViewById(android.R.id.button1). I do have a button with the id "button1". When I closed the project and restarted it and after I  waited for Gradle to finish loading and the error disappeared. Why does this happen?</p>