Other Things in the Project Tree

The project tree, starting at the HelloWorld/ root node, contains all of the stuff that makes up the project. However, the project tree itself also contains two other root nodes: “External Libraries” and “Scratches and Consoles”.

External Libraries

The more important of the two, by far, is “External Libraries”, though you will only need to examine this area of the project tree on occasion.

MainActivity is fairly small. It can be that small because “it stands upon the shoulders of giants”. In this case, those “giants” are libraries.

Our tiny app pulls in a very long list of libraries:

This is not a complete list — the list is so long, it cannot fit in a single screenshot.

Most of these libraries come from Google and are part of the Android SDK. Some are from other developers, such as libraries from JetBrains in support of Kotlin.

We will see in an upcoming chapter where these libraries come from and why they are all being used to build this little app.

Scratches and Consoles

The last item, “Scratches and Consoles”, is almost completely undocumented and seems to be infrequently used. Among other things, via the right-mouse context menu, you can create new “scratch files” here, useful for notes or testing programming language syntax outside the scope of actual project code.