Android Studio is a very deep tool, but it is only necessary to learn one part at a time in order to get started. What might be useful for us is naming a few parts of the UI so that we can refer to them easily as we progress through the book.

Take a look at this numbered diagram and a quick explanation of some of the key parts of Android Studio. If you can, try and memorize the parts to make future discussions of them easier for you.

Here is a handy table that you can quickly refer to and remember which part of Android Studio we are referring to. What follows is a more detailed explanation of each area.

The Android Studio editor window is a very dynamic area. It presents different file types in the most useful way possible. A little earlier, when we created our project, it also made a basic UI for us. UIs in Android can be built-in Java code or, as we will see, in a visual designer without the need for a single line of Java. However, as we will investigate after we have built the UI of our game menu, to get the UI to do anything useful, we need to interact with it. This interaction is always done with Java code. The visual designer also generates the UI code for us. We will take a very quick look at that too.

As the book progresses, we will mainly shy away from Android UI development, as that is a staple of more non-game apps. We will instead spend more time looking at directly drawing pixels and images to make our games. Nonetheless, the regular Android UI has its uses, and the Android Studio visual designer is the quickest way to get started.

Let...

If you have ever used an Android device, you have probably noticed that it works quite differently from many other operating systems. For example, you are using an application—say you're checking what people are doing on Facebook. Then you get an e-mail notification and you tap the e-mail icon to read it. Midway through reading the e-mail, you might get a Twitter notification and because you're waiting on important news from someone you follow, you interrupt your e-mail reading and change the app to Twitter with a touch.

After reading the tweet, you fancy a game of Angry Birds, but midway through the first daring fling, you suddenly remember that Facebook post. So you quit Angry Birds and tap the Facebook icon.

Then you resume Facebook, probably at the same point you left it. You could have resumed reading the e-mail, decided to reply to the tweet, or started an entirely new app. All this backwards and forwards takes quite a lot of management...

So what about all that code that Android Studio generated when we created our new project earlier? This is the code that will bring our game menu to life. Let's take a closer look. The very first line of code in the editor window is this:

package com.packtpub.mathgamechapter2;

This line of code defines the package that we named when we first created the project. As the book progresses, we will write more complex code that spans more than one file. All the code files we create will need the package they belong to, clearly defined like the previous line of code, at the top. The code doesn't actually do anything in our game. Notice also that the line ends with a semicolon (;). This is a part of the Java syntax and it denotes the end of a line of code. Remove a semicolon and you will get an error because Android Studio tries to make sense of two lines together. Try it if you like.