Build Your First Android App with Android Studio

Now that you've got all the tools and the Android SDK installed, it's time to get started! Just like in many programming books, we'll begin with a classic: the HelloWorld application. This will help you explore the different parts that make up an Android project. So, without any delay, let's jump right in!

In our earlier article, we successfully installed "Android Studio." In case you haven't installed Android Studio yet, I recommend you to read this article for guidance.

Setting Up Android Virtual Device (AVD) for App Testing

This guide provides step-by-step instructions on how to set up an Android Virtual Device (AVD) for testing Android apps on your computer. AVD allows you to simulate various Android devices for app development and testing purposes.

A program typically does something with data, and an Android app is no different. It processes information, displays content on the screen, and gathers data from various sources. Developing Android apps for devices with limited resources requires understanding the application lifecycle. In this unit, you'll get to know the essential components of Android apps and learn how to create and run one.

Building a sample Android application using Android Studio

Before diving into complex app development, it's important to make sure that all the necessary development packages are installed and working correctly. The easiest way to do this is by creating a basic Android app, compiling it, and running it. 

Let's walk through the steps of creating a simple Android app project using Android Studio. Once the project is set up, we'll later explore using the Android emulator to test the app.

Creating a New Android Project

The initial and foremost step in creating your app involves setting up a new project within the Android Studio environment. 

To begin, open Android Studio. 

As soon as you launch the application, you'll be greeted by the "Welcome to Android Studio" screen.

Moving forward, our next step involves generating a new project. 

Simply click on the "New project" option. This action will open up a selection of templates. 

Choose the "Phone and Tablet" category, and then select the "Empty Views Activity" template. Once you've made your selection, click "Next" to continue.

In the New Project window, you'll find a field labeled "Application name," and enter "HelloWorld" as the name of your application. 

This name will be used to identify your app within Android Studio and will also be displayed when your fully developed app is available on the Google Play store.

The Package Name serves as a unique identifier for your application within the larger Android application environment. To create this name, use a pattern based on the reverse URL of your domain name combined with your app's name. 

For example, if your domain is www.example.com, and your app is named HelloWorld, your package name could be "com.example.HelloWorld". This distinctive package name ensures that your app stands out within the Android ecosystem.

The default Project location is initially set to a directory called "Android Studio Projects" within your home folder. Nevertheless, you have the option to modify this location by clicking the button located to the right of the current path field. 

Once you've determined the desired location, proceed to select the Programming Language. Although Android Studio offers various language options, I recommend choosing Java.

Set the minimum SDK version to API 16, which corresponds to Android 4.1 (Jelly Bean). Opting for an older SDK version ensures compatibility across a wider range of Android devices. 

Keep in mind that selecting a higher minimum SDK version limits the app's compatibility with newer devices.

Once these settings are configured, click on "Finish" to initiate the project creation process. 

Upon clicking "Finish," Android Studio will automatically download the necessary resources, and this step may take some time to set up the project files.

 

Running the HelloWorld Application

With your project now set up, it's time to take your first step into running your Android app!

In the top bar of Android Studio, you'll find a selection of Android virtual devices. Choose the one that suits your needs, or connect your physical device via Wi-Fi. 

Following this, locate and click the "Run App" button in the taskbar.

Allow a moment for the Android emulator to initialize. Once it's up and running, Android Studio will automatically deploy your app onto the selected virtual device.

With the application launched, you'll witness it on the screen. For a clearer understanding, you can refer to the visual illustration provided.

To exit the application, simply click the Home button on the emulator. 

Upon accessing the Application Drawer, you'll notice the installed applications, which mirror the image provided.

If you find yourself with several compatible AVDs in operation, Android Studio will open the Android Device Chooser window. Within this tool, you have the freedom to select the particular emulator or device you intend to use for debugging your application.

If there is any uncertainties or questions arise, feel free to share them in the comments section below. Your inquiries are most welcome!