How To Write Your First Google Android Application
Android is the most popular mobile operating system in the world right now. By developing an Android app, you get to appeal to a multi-million audience and increase the odds of going viral.
Although there’s a common misconception that Android apps are challenging to build, the reality is, it takes a moderate amount of effort and perseverance to create your own mobile product.
If you want to create an Android app and have no idea where to start, this guide is a full walk-through for novice developers.
Prerequisites For Building Android Apps
Although software engineers use integrated development environments to work on projects, there’s no way to write first google android app without programming skills. Here are the must-have skills for an Android developer:
- A solid command of Java and Kotlin (optional). Most IDEs are geared towards Java-based apps. Even if you prefer Kotlin, having a basic understanding of Java’s syntax and working principles is essential for navigating Google’s Android Studio freely.
- Understanding of how integrated development environments work. Whether, Android Studio, or VisualStudioCode, a developer needs to be familiar with the features of assistive development tools, ways to configure virtual devices, customize the workplace, and use the interface builder.
- Be familiar with database management and SQL. Fetching data from the server, handling files, and capturing user data requires a solid command of RoomDatabase and SQL
- REST and API knowledge to handle HTTP/HTTPs communications.
If you meet all of the prerequisites, you are ready to write first google Android app from scratch. If not, surf the web for learning resources and hit the books.
The good news is, you don’t need to own an Android device to develop an app. Software engineering teams handle the bulk of work via a computer. Later, a complete app could be sent to a physical device for testing – if you don’t have one, there are plenty of emulators that can substitute Android smartphones.
Developing Android Apps in Eclipse
Step #1. Downloading the resources
A developer starts working on an Android project by setting up an environment. At first, you need to download the Java JDK. There are 64-bit and 86x versions – most teams prefer the latter for performance stability.
Then, an Android developer has to download an Android SDK. The software development kit includes Eclipse – an integrated development environment, design components, and other tools.
You can download the Android Bundle for free. Open the archive, choose a directory on the local drive, and unzip it there.
Step #2. Configuring the environment
Go to ADT Bundle -> SDK -> Eclipse and open the Eclipse installer. When the IDE opens, a developer can customize the workplace – for beginning developers, it’s recommended to stick to default settings.
After choosing ‘OK’ and closing the pop-up tab, choose the Android SDK icon. Eclipse will suggest a list of additional resources to download – tick the following packages:
- Google APIs;
- Documentation for Android SDK;
- SDK samples.
There are more additional packages – you can download them on-demand anytime. The rule of thumb is to stick to essential resources to not slow the system down and avoid the increase of the download time.
Step #3. Create a virtual device
Choose the Android Virtual Device Manager icon from the toolbar. The tab that opens is the AVD manager – it allows developers to test and debug ready projects. The workspace requires slight customization to be fully comfortable:
- Choose a device you want to test based on the model, OS version, and screen dimensions.
- Choose if you want to boost the performance of the AVD using the GPU of the system. Although it slows down other applications that are running on a computer, allowing the IDE to use GPU helps speed up the development process – that’s why ticking the box is standard practice.
- Tweak the amount of RAM an emulator can consume in case you want to save more disk space.
- Once the AVD is configured, leave the tab running in the background.
Step #4. Creating a new Android project
To start developing an app, choose File -> New -> Android project. The IDE will offer additional tweaks – leave the settings at Default. Be sure to choose the SDK that corresponds to the one you downloaded.
Setting up the workplace takes a couple of minutes – during this time, it’s better to run no software in the background. When the development is configured, a developer needs to customize the app.
Step #5. Build the app
As soon as there’s a screen with ‘Hello World’ on it, you can work on changing app screens and adding new elements. A developer can either use the drag-and-drop interface of the IDE to customize the style of the screen or code manually for more freedom.
Once done, an Android software engineer presses Save. Now the app is fully ready and can be run via a virtual device.
Step #6. Running the app
To the left of the screen, choose the src. folder. From there, go to com.example.helloworld ->mainactivity.java. As a developer chooses the file, he can click on a green ‘Play’ icon that will run the app.
It will take a while for a virtual device to set up properly. Once it’s ready, you will see the output of your app. The first Android ‘application’ most beginner developers design is a simple string of ‘Hello World’ text.
Developing Android Apps in Google Android Studio
Step #1. Installing the IDE
You can download the official Android Studio for free. After you have the file, follow the installation instructions.
Step #2. Create a new project
Open the software. Go to the Quick Start menu and choose ‘Start a new Android Studio project’. Specify the location of the project, make sure no other boxes except for ‘Smartphone’ and ‘Tablet’ are checked. Choose an SDK, and click ‘Finish’ to close the setup tab.
Step #3. Edit the main activity
Choose activity_main.xml. Make sure the Design toolbar is visible. Drag and drop the ‘Hello World’ and ‘Welcome to my app’ lines to the display. You can edit the text by double-clicking on it.
Step #4. Add interface elements
In the Design tab, find the ‘Widgets’ folder. To add a button, choose a corresponding element and drag it to the workspace. To edit the text on the element, go to ‘Properties’, find ‘Text’, and edit the caption to the one you like.
Step #5. Creating new activities
To manage multiple activities, choose New -> Activity -> Blank activity in the app’s system tree. You can edit a new as you did the first one by dragging and dropping text and visual elements.
Step #6. Creating methods
You can start creating methods for your app by adding a ClickOn method to the button. You can edit the method by choosing MainActivity.java. Don’t forget to add import statements as well.
Step #7. Test the app
To run the app, choose a green ‘Play’ icon in the top toolbar of the window. Choose a device you want to try running the code on, choose ‘Launch emulator’. After a short while, the code will be executed automatically.
Without extensive coding knowledge, you will quickly feel out of depth and will struggle to bring the app to completion.
As soon as a developer reaches an intermediate level of Java proficiency, he can leverage the full potential of integrated development environments and work on fully functional projects.