I have been through a few books on Android Programming and the official site of Google for Android Devlopers, it appears the development is moving towards using Constraint Layout completely. Even the Android Studio Version 3.0.1 uses Constraint Layout as default.
Why then we still find books and stuffs starting UI introduction with Relative Layouts and not Constraint Layouts. Is it so because modifying XMLs still gives us Java hangover or it is difficult to explain Constraint Layout initially which is so much dependent on views and looks (nothing is meant to be modified in XML).
This was initially a problem for me where I started with Relative Layouts and then found every explanation is trying to use Constraint Layouts now.
Any views on this?