The project structure

We can examine the project structure in the project navigation pane using the Project view type. The project structure includes a folder with the name of our application. This folder contains the application structure and files. The most important elements of the application structure are in the app directory. These include the following:

• build/: This is a folder that contains the resources compiled after building the application and the classes generated by the Android tools, such as the R.java file that contains the references to the application resources.
• libs/: This is a folder that contains the libraries referenced from our code.
• src/androidTest/: This is a folder that contains the test classes of the Java classes that need to be tested.
• src/main/: This is a folder that contains the sources of our application. All the files you will usually work with are in this folder. The main folder is subdivided as follows:
  • java/: This is a folder that contains the Java classes...