In today’s fast-paced development environment, building applications that run seamlessly across multiple platforms is essential. Capacitor, a library from the Ionic team, revolutionizes the landscape for hybrid app development by allowing developers to use one codebase for all platforms. In this guide, we will walk through how to build a simple JavaScript application and compile it for iOS, Android, Windows, MacOS, and as a web app, all in just five minutes.

What is Capacitor?

Capacitor is a modern alternative to Apache Cordova that allows developers to create hybrid applications for mobile and desktop. It puts Progressive Web Apps (PWAs) on an equal footing with native applications, meaning developers can write their code once and deploy it across various platforms without constant adjustments and changes. This significantly enhances productivity by simplifying the development process.

Why Choose Capacitor?

• Cross-Platform Compatibility: Write once, run everywhere.
• Easy Integration: Works with any JavaScript framework or plain JavaScript.
• Native Functionality: Access native SDKs using familiar web technologies.
• Streamlined Development: Focus more on coding and less on platform specifics.

Step-by-Step App Development with Capacitor

Now that we understand what Capacitor is, let’s jump into building a simple application. For this demo, we will be using Angular, but it’s important to remember that Capacitor can work with any JavaScript framework.

Step 1: Set Up Your Environment

First, open up your favorite Integrated Development Environment (IDE) and create a new Angular CLI app. After initializing your project, start by installing the Capacitor CLI by running the following command in your terminal:

npm install @capacitor/cli --save-dev

This will install the Capacitor CLI in your project.

Step 2: Initialize Your App

Once installed, initialize your app using:

npx cap init

You’ll need to provide an app name and a package ID (e.g., com.example.app), which is crucial for mobile apps. This command creates a configuration file named capacitor.config.json in the root directory of your project. It’s essential to change the webDir property to dist, as Angular compiles its output to the dist folder.

Step 3: Build Your App

Next, compile your Angular app by executing:

ng build --prod

Then, serve the app using Capacitor by running:

npx cap serve

This command will run your app as a Progressive Web App (PWA) in your browser.

Step 4: Build a Feature Using Native SDKs

We will implement a simple geolocation feature that requires interacting with native SDKs. Create a button in your app component that, when clicked, retrieves the user’s current latitude and longitude.

1. Setup the Button: In the HTML of your component, define a button that will call a method to show the coordinates on click.
2. Typescript Configuration: Import the necessary plugins from @capacitor/core. For geolocation, you will need to import the Geolocation plugin:
   typescript import { Plugins } from '@capacitor/core'; const { Geolocation } = Plugins;
3. Listening to Geolocation: The Geolocation plugin returns a stream of data based on geographical changes. Convert this to an observable for effective data management in Angular:
   typescript const watch = Geolocation.watchPosition();
4. Alert Dialogs: Use modal dialogs to display messages that differ based on the platform running the app.

The finalized code allows you to fetch and display the user’s location seamlessly across different devices.

Step 5: Run on Multiple Platforms

1. Adding Android Platform: Run the following command to add Android capabilities:
   bash npx cap add android
2. Build for iOS: Similarly, add iOS support by using:
   bash npx cap add ios
3. Desktop Applications: To create Windows and MacOS applications, Capacitor can be used with Electron. Simply run:
   bash npx cap add electron
4. Build Electron Apps: Once inside the Electron directory, run:
   bash npm install electron-packager npm run build

You’ll have compiled your application for five platforms: iOS, Android, Windows, MacOS, and as a PWA, all in just under five minutes!

Conclusion

Capacitor provides a robust foundation for developing cross-platform applications, making the lives of developers easier by ensuring one codebase runs seamlessly across all devices. While Capacitor is still in its alpha phase, it holds significant promise for the future of hybrid app development.

With Capacitor in your toolkit, you can utilize native functionalities without the usual headaches that come with managing different platforms. As the development industry continues to evolve, being ahead of the curve with emerging tools like Capacitor can give you a significant advantage.

If you’re serious about mobile app development, consider exploring Capacitor further and embrace the potential it offers to revolutionize your workflow!