RRO (Runtime Resource Overlay) in Android AOSP
Today I am going to discuss a very important android resource framework.
Run-time Resource Overlay as its name suggests, is resource overlay and it can be applied at run-time. I may guess not many of you know about it and google never advertises this AOSP resource framework. The android operating system has had this theming framework (RRO) built into AOSP for a few years now. With the help of RRO, we can quickly create themes that can change the look and feel of almost every app that’s installed on an Android device.
As for example — system user interface components, including navigation bar, status bar, notifications tray, and quick settings tray, themselves belong to an app, you can change their looks too. And the best part about it is that you don’t have to write any Java code whatsoever for this RRO.
What’s the catch, you ask? Well, this framework(RRO) can be used only by privileged apps i.e. apps that are installed in a location that can be accessed only by the root user, or by someone who’s (like us 😎) creating a custom ROM.
RRO work Mechanisms
- Android app’s business logic is written in Java or Kotlin and its user interface is primarily created using XML files.
- A well-written Android app will have separate XML resources that…
