Android: Application Project Structure in Eclipse

The Android project (under Eclipse ADT) consists of several folders:
Android - Project folder structure

  • src: Java Source codes. The Java classes must be kept in a proper package with at least two levels of identifiers (e.g., com.example...).
  • res: Resources, including drawable (e.g., images, icons), layout (UI components and layout), values (e.g., locale strings).
  • gen: Generated Java codes (e.g., to reference the resources) by Eclipse's ADT.
  • AndroidManifest.xml: The manifest to describe the structure of the application.
  • bin: Compiled bytecodes and packaging information.
The binaries together with their resources are bundled into an Android Package Archive file (with ".apk" file extension) via the "aapt" tool, for distribution and installation into the mobile devices.