React Native is an incredibly powerful tool used for cross-platform app development. It allows developers to build mobile applications by using their existing knowledge of JavaScript.
If you are new to React Native, it is essential to properly set up your application and follow best practices in order to avoid potential pitfalls. By taking the time to properly configure your environment and adopting best practices for coding, you can streamline your development process and create high-quality, performant applications.
So why not give it a try and see how React Native can help you build the next great mobile application?
Let’s get started with this blog!
What Is React Native?
Before we dip deeper into the process of building a cross-platform mobile application, let’s first talk about what React Native actually is and how it works.
React Native is a powerful library for building dynamic and responsive user interfaces. It was created and open-sourced by Facebook in 2017 and since then it has become one of the most widely used technologies for mobile app development services.
React Native comes with a lot of advantages such as:
- React Native applications are typically lightweight and fast, even when dealing with large amounts of data or complex user interactions.
- Another key benefit of React Native is its component-based architecture. This allows developers to break their applications down into smaller, reusable building blocks, making it easier to write and maintain clean, modular code.
- React Native uses a different set of components and styling techniques to work seamlessly across different mobile platforms.
React Native Is Actually Native
One of the best advantages of React Native is that “it is actually Native”. React Native uses a “bridge” to communicate between the JavaScript code and the native platform code, which allows developers to use native UI components such as buttons, text fields, and views.
When you write code in React Native, the framework compiles it into native platform code at runtime, which means that the app you build with React Native is not a web app running in a browser, but a fully native app running on the device. This is what makes React Native “actually native.”
React Native also provides APIs to access native device features such as camera, GPS, and accelerometer, allowing developers to build apps with a native look and feel and take advantage of the unique capabilities of each platform.
How To Build a Cross-platform Mobile App With React Native
Getting Started
Before beginning to build your React Native project, it is important to ensure that you have Node.js installed on your computer. As it is a JavaScript runtime environment that allows you to run JavaScript code outside of a web browser.
To install Node.js, you can visit the official Node.js website and download the appropriate version for your operating system. Once Node.js is installed, you can proceed to install the create-react-native-app command line utility.
To do so, you can open a new terminal window and run the below command:
npm install -g create-react-native-app
After this create a new project by running the following command.
create-react-native-app YourAppName
The next step is to navigate to the folder where you want to create your React Native project. You can do this by opening a terminal window and navigating to the desired folder using the “cd” command.
cd myNewApp
npm start
If you have used create-react-native-app to build your React Native project via the command line, you can easily test your application using the Expo client app. The Expo client app is available for download from the iOS App Store or Google Play Store. It allows testing and debugging apps on a physical device without the need for complicated configurations or deployments.
To use the Expo client app, you will need to make sure that your device is connected to the same Wi-Fi network as your computer. Then, from the terminal window where you started the development server using “npm start”, you can scan the QR code displayed on the screen using your device’s camera.
Alternatively, if you do not have access to a physical device, you can use an iPhone or Android simulator to test your app. This requires Xcode installation for iOS simulators or Android Studio installation for Android simulators.
Ordinary React Components
// iOS & Android
var React = require(‘react-native’);
var { ScrollView, TouchableHighlight, Text } = React;
var TouchDemo = React.createClass({
render: function() {
return (
<ScrollView>
<TouchableHighlight onPress={() => console.log(‘pressed’)}>
<Text>Proper Touch Handling</Text>
</TouchableHighlight>
</ScrollView>
);
},
});
In this example, we import the necessary components from React Native, including ScrollView, TouchableHighlight, and Text. The ScrollView component is used to create a scrollable container for our content, and the TouchableHighlight component is used to provide touch handling for each item in the scroll view.
Within the ScrollView component, we create a series of TouchableHighlight components, each containing a Text component with some example content. When the user taps on one of these items, the TouchableHighlight component will handle the touch event and trigger some action (which we haven’t defined in this example).
Overall, this is a basic example of how you can use React Native components to create a scrolling view with touch handling. Of course, you can customize the appearance and behavior of these components to fit your specific needs.
Stylesheets
React Native implements a subset of CSS to simplify rendering and promote maintainable styling code. With this approach, you don’t have to learn a platform-specific way of designing views, but you will need to familiarize yourself with React Native’s style syntax.
One major difference is the lack of specificity rules. React Native restricts style inheritance and relies on inline styles, making it easier to manage and maintain your styling code.
Below is an example of how stylesheets are created in React Native.
var styles = StyleSheet.create({
container: {
flex: 1,
marginTop: 30
}
});
After this, the respective style is applied using the inline syntax.
<View style={styles.container}>
…
</View>
Setting Up For Mobile App Development
Setting up a development environment for React Native can be a bit of a challenge, as it requires you to have a variety of tools and software in place. To start, you’ll need the standard mobile development tools, as well as a good text editor and debugging tools like the Chrome Developer Console.
If you’re developing for iOS, this means you’ll need to have Xcode up and running, along with the iOS simulator. For Android, you won’t need Android Studio – instead, you’ll be working with the command-line tools. Additionally, you’ll need to make sure that the React Native packager is running properly.
With all of these tools in place, you can use your preferred text editor to write and edit your JavaScript code. Overall, getting your development environment set up may take some time and effort, but it’s an essential step in building high-quality React Native applications.
React Native is designed to provide JavaScript interfaces to platform-specific APIs, which can be leveraged through normal React code. However, in some cases, the React Native bridge may not support certain API calls. In such situations, developers can create “native modules” to facilitate communication between their JavaScript code and the host platform.
Jumping Down Into Native Code
React Native provides a powerful platform for building cross-platform mobile applications using JavaScript and React. It achieves this by providing JavaScript interfaces to existing platform APIs. This allows developers to write code that looks like ordinary React code, while the React Native bridge handles the heavy lifting of communicating with the underlying platform.
However, as with any technology, there may be instances where the bridge is incomplete, and certain API calls are not supported by the framework. In such cases, developers can write native modules to communicate between the host platform and their JavaScript code.
Below is an example of an Objective-C module.
// Objective-C
#import “RCTBridgeModule.h”
@interface MyCustomModule : NSObject <RCTBridgeModule>
@end
@implementation MyCustomModule
RCT_EXPORT_MODULE();
// Available as NativeModules.MyCustomModule.processString
RCT_EXPORT_METHOD(processString:(NSString *)input callback:(RCTResponseSenderBlock)callback)
{
callback(@[[input stringByReplacingOccurrencesOfString:@”Goodbye” withString:@”Hello”]]);
}
@end
After this to use your native module from JavaScript, you can require it like any other library.
// JavaScript
var React = require(‘react-native’);
var { NativeModules, Text } = React;
var Message = React.createClass({
getInitialState() {
return { text: ‘Goodbye World.’ };
},
componentDidMount() {
NativeModules.MyCustomModule.processString(this.state.text, (text) => {
this.setState({text});
});
},
render: function() {
return (
<Text>{this.state.text}</Text>
);
}
});
In some cases, you may find that the APIs you need is not yet supported by React Native, or you may need to integrate your React Native components with existing Objective-C or Java code. Additionally, there may be instances where you need to write high-performance functions to handle intensive graphics processing. In such scenarios, React Native gives you the flexibility to write and use native modules to bridge the gap between the JavaScript code and the native platform-specific code.
Deploying The Application
When building a React Native app for production deployment, it’s important to switch from the live-reloading development version of the JavaScript code to a bundled version that is optimized for performance and stability.
To do this on iOS, you’ll need to make a simple change to your AppDelegate.m file by updating a single line of code. You’ll then need to run the “react-native bundle –minify” command, which will create a compressed and optimized bundle of your JavaScript code.
On Android, the process is slightly different. You’ll need to run the “./gradlew assembleRelease” command, which will create an APK file that contains your optimized JavaScript code along with any other necessary assets.
Once you have your optimized bundle, you can then submit your app to the relevant app store(s) for distribution. This process is the same as for any other mobile app, and you’ll need to follow the relevant guidelines and requirements for each platform.
The iOS app store took almost two weeks to approve the app while the Google Play Store took less than a day.
Challenges To Overcome During React Native App Development
- One of the biggest challenges of cross-platform app development is dealing with platform-specific bugs. While React Native offers a single codebase for both platforms, each platform has its own unique quirks and behaviors that can lead to bugs and errors.
- Mobile apps need to be fast and responsive to provide a good user experience. However, React Native apps can sometimes suffer from performance issues, especially when dealing with large data sets or complex UI elements.
- While React Native provides many built-in modules for accessing device features, there may be times when you need to integrate with a native module that is not available in React Native.
Conclusion
In conclusion, building a cross-platform mobile app with React Native for iOS and Android platforms is an excellent choice. In this step-by-step guide, we have covered all the basics from setting up the development environment to deploying the app.
We hope this blog will prove helpful to build your next mobile app with React Native. By following the outlined steps and best practices, you can confidently develop a high-quality mobile app that meets the needs of your users and stands out in a crowded market.
Author bio- Amara works with the editorial team of DianApps, a leading React Native Development Company offering React Native app development services. Exploring the latest technologies, reading about them, and writing her views have always been her passion. She seeks new opportunities to express her opinions, explore technological advancements, and document the details. You can always find her enjoying books or articles about varied topics or jotting down her ideas in a notebook.
