Android system architecture

The Android system uses a layered architecture that consists of four layers: application layer, framework layer, system Runtime Library, and Linux kernel.

The application layer is mainly used to run Android applications.ProgramIncluding system applications and user applications. Applications are written in Java (SDK) or Java + C/C ++ (ndk.

The framework layer is mainly provided to the application layer API interface. The main components of the framework layer include activity manage, Window Manager, content providers, view system, notification manager, Package Manager, resources manager, and hardware services.

The system runtime layer mainly provides services for developers through the android framework layer. Core libraries mainly include surface manager, media framework, SQLite, open gl es, SGL, free type, WebKit, SSL, and libc.

Linux kernel layer, mainly based on linux2.6.