Project's Folder Structure

1.     src(Source folder)/: holds the Java source code for the application.

2.     gen(generated folder)/ : contain R.java file. R.java file contains the id’s of all component in hex code.

3.     assets/: holds other static files you wish packaged with the application for deployment.

4.     res(resource)/ holds resources, such as icons, GUI layouts, and the like, that get packaged with the compiled Java in the application.

5.     AndroidManifest.xml: an XML file describing the application being built and what components—activities, services, etc.—are being supplied by that application.

6.     default.properties, a property file used by the Ant builds script.