Java for Android, Second Edition
Each of the Android projects comes as an Android Studio project. When opening an Android Studio project for the first time:
1. If you see a message saying 'The path ... does not refer to an Android SDK. Android Studio will use its default SDK instead,' click OK.
3. If you see a message saying 'Failed to sync the Gradle project .... Fix plugin version and re-import project,' simply click the link to agree.