Handling Installation Prompts in Progressive Web Apps

Introduction

Progressive Web Apps (PWAs) provide a native app-like experience on the web. One of their core features is the ability to be installed on a user's device. This lesson focuses on how to handle installation prompts effectively.

Key Concepts

• Service Worker: A script that runs in the background, enabling features like offline support.
• Web App Manifest: A JSON file that provides metadata about the app (name, icons, start URL, etc.).
• BeforeInstallPrompt Event: A browser event that indicates the app can be installed.

Handling Installation Prompts

To manage installation prompts, you can listen for the beforeinstallprompt event. This event gives you control over the installation process.

Step-by-Step Process

1. Ensure your PWA is configured with a valid Web App Manifest.
2. Register a service worker in your app.
3. Listen for the beforeinstallprompt event:

            let deferredPrompt;

            window.addEventListener('beforeinstallprompt', (e) => {
                // Prevent the mini info bar from appearing on mobile
                e.preventDefault();
                // Stash the event so it can be triggered later
                deferredPrompt = e;
                // Update UI to notify the user they can add to home screen
                showInstallButton();
            });

            installButton.addEventListener('click', () => {
                // Show the prompt
                deferredPrompt.prompt();
                // Wait for the user to respond to the prompt
                deferredPrompt.userChoice.then((choiceResult) => {
                    if (choiceResult.outcome === 'accepted') {
                        console.log('User accepted the A2HS prompt');
                    } else {
                        console.log('User dismissed the A2HS prompt');
                    }
                    deferredPrompt = null;
                });
            });
            

Best Practices

• Show the prompt at an appropriate time, such as after a user has engaged with your app.
• Provide a clear and appealing explanation of the benefits of installing your app.
• Consider using a custom install button that matches your app's design.

FAQ