Progressive Web Apps: Cross-Plattform-Apps auf Desktopniveau

Progressive Web Apps sind ein großartiges Anwendungsmodell auf Basis von Webtechnologien, das sich stetig weiterentwickelt hat: In den letzten Jahren kamen dank der Initiative Project Fugu viele neue Schnittstellen ins Web, die PWAs auf Desktopniveau gehoben haben. In diesem Jahr können PWAs endlich auch auf iPhones Pushbenachrichtigungen empfangen. Christian Liebel von Thinktecture stellt das Anwendungsmodell mit seinen Möglichkeiten und Einschränkungen vor. Schauen Sie also vorbei, wenn auch Sie Ihre App nur einmal schreiben und auf etlichen Geräten, Browsern und Betriebssystemen verwenden wollen!

Transcript

1. Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Christian Liebel @christianliebel Consultant
2. Hello, it’s me. Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Christian Liebel Twitter: @christianliebel Email: christian.liebel @thinktecture.com Angular & PWA Slides: thinktecture.com /christian-liebel
3. Cross-Plattform-Apps auf Desktopniveau Progressive Web Apps Responsive Linkable Discoverable Installable App-like Connectivity Independent Fresh Safe Re-engageable Progressive
4. Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Demo Use Case
5. Cross-Plattform-Apps auf Desktopniveau Progressive Web Apps
6. Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Target Platforms PROGRESSIVE WEB APPS + cars, smart fridges, …
7. Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Web App Manifest Service Worker
8. Web App Manifest Distinguishes Web Apps from Websites JSON-based file containing metadata for apps only Apps can be identified by search engines, app store providers, etc. Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau PWA
9. manifest.webmanifest { "short_name": "Paint", "name": "Paint Workshop", "theme_color": "white", "icons": [{ "src": "icon.png", "sizes": "512x512" }], "start_url": "/index.html", "display": "standalone", "shortcuts": [/* … */] } Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau PWA Names Icons Display Mode Shortcuts Start URL Theme color (status bar/window bar)
10. Manifest Display Modes Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau PWA browser minimal-ui standalone fullscreen
11. Manifest Icon Purposes (any) any context (e.g. app icon) monochrome different color requirements (at risk) maskable user agent masks icon as required Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau PWA Safe Zone Windows iOS Android
12. Manifest Shortcuts Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau PWA Secondary entrypoints for your application (e.g., home screen quick actions, jump lists, …) Static definition in Web App Manifest Dynamic API may follow in the future Supported by Google Chrome for Android, macOS and Windows
13. Web App Manifest – Chrome Install Criteria 1. Web App is not already installed 2. Meets a user engagement heuristic (user has interacted and clicked with origin for at least 30 seconds) 3. Includes a Web App Manifest that has short_name or name, at least a 192px and 512px icon, a start_url and a display mode of fullscreen, standalone or minimal-ui 4. Served over HTTPS 5. A service worker is no longer required! Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau PWA https://web.dev/install-criteria/
14. Service Worker JavaScript executed in an own thread, registered by the website Acts as a controller, proxy, or interceptor Has a cache to store responses (for offline availability and performance) Can wake up even when the website is closed and perform background tasks (e.g., push notifications or sync) Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau PWA
15. Service Worker Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau PWA Service Worker Internet Website HTML/JS Cache fetch
16. Workbox Toolchain by Google Includes a CLI Generates a service worker implementation from directory contents (e.g., build output, or our development directory) Allows you to modify the service worker behavior (maximum flexibility) Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau PWA
17. Push Notifications Just as native apps, PWAs can receive push notifications Combination of two technologies: Web Notifications and Push API Supported by Chrome, Edge, Firefox, Safari Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau PWA
18. Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau
19. Project Fugu Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Capabilities »Let’s bring the web back – API by API« Thomas Steiner, Google
20. https://paint.js.org – Productivity app – Draw images – Lots of actions & tools – Installable – Read/save files – Copy/paste images from/to clipboard – Share files to other apps – Register for file extensions Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Demo Use Case
21. Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Capabilities Contacts Picker Screen Wake Lock API File System Access API Shape Detection API
22. Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Capabilities https://goo.gle/fugu-api-tracker
23. Browser Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Capabilities navigator.share({ url: 'http://example.com' }); ShareIntent DataTransferManager … NSSharingServicePicker
24. File System Access API Some applications heavily rely on working with files (e.g. Visual Studio Code, Adobe Photoshop, …) File System Access API allows you to open, save and override files and directories Supported by Chrome, Edge Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Capabilities
25. Async Clipboard API Allows reading from/writing to the clipboard in an asynchronous manner (UI won’t freeze during long-running operations) Supported by Chrome, Edge and Safari and Firefox (plain- text only) Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Capabilities
26. Web Share API Allows sharing a title, URL, text, or files API can only be invoked as a result of a user action (i.e. a click or keypress) Supported by Chrome, Edge, Safari and Firefox (Android only) Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Capabilities
27. File Handling API Register your PWA as a handler for file extensions New: Ability to define icons Requires installing the application first Declare supported extensions in Web App Manifest and add imperative code to your application logic Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Capabilities
28. Overview Use available interfaces and functions of a system (opposite of Graceful Degradation) Users with modern, feature-rich browsers get a better experience Apps are available on older browsers, but with limited functionality Concept: Browser feature support should grow over time—thereby more users can enjoy an increasing number of features Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Progressive Enhancement
29. Overview if ('serviceWorker' in navigator) { navigator.serviceWorker.register(…) .then(() => /* … */); } In JavaScript: check whether an API/feature is available. If yes—use it! Otherwise: 1. Disable the functionality 2. Fall back to an alternative API (if available) Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Progressive Enhancement
30. Isolated Web Apps – Packaged and signed for stronger security – Deployed through app stores, platform- specific bundles or installers – These additional trust anchors enable even more powerful APIs (e.g., Direct Sockets API) for IWAs – Still web-based, cross-platform and using open standards – But without the bloat of Electron Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Outlook
31. Isolated Web Apps Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Outlook JS HTML CSS Enterprise Deploy App Store MSI, APK, … Signed Web Bundle Platform- specific
32. Spotify Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Use Cases https://open.spotify.com/
33. VS Code Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Use Cases https://vscode.dev/
34. Photoshop Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Use Cases https://creativecloud.adobe.com/cc/photoshop
35. Progressive Web Apps are now installable, offline-capable and able to receive push notifications on all operating systems New powerful APIs regularly ship with new releases of Chromium-based browsers If needed, you can still wrap your application in a platform-specific package à your investment in web apps always pays off! Let’s make the web a more capable platform! Progressive Web Apps Cross-Plattform-Apps auf Desktopniveau Summary
36. Thank you for your kind attention! Christian Liebel @christianliebel christian.liebel@thinktecture.com