Web Components: What, Why, How, When

Revised and updated version of an older talk, presented at the Web Components London meetup.

Transcript

1. @stopsatgreen WEB COMPONENTS What, Why, How, When #WCLDN, 04/03
2. @stopsatgreen @stopsatgreen Peter Gasston broken-links.com
3. @stopsatgreen WEB COMPONENTS
4. @stopsatgreen http://en.wikipedia.org/wiki/H%C3%A9lio_Oiticica
5. @stopsatgreen
6. @stopsatgreen WHAT?
7. @stopsatgreen “The component model for the Web.”
8. @stopsatgreen A suite of technologies for making reusable UI controls or services.
9. @stopsatgreen Fundamental change to the way we build the Web.
10. @stopsatgreen
11. @stopsatgreen
12. @stopsatgreen
13. @stopsatgreen ® The Lego Group
14. @stopsatgreen Custom Elements + Shadow DOM + HTML Imports + Templates = Web Components
15. @stopsatgreen WHY?
16. @stopsatgreen
17. @stopsatgreen OOCSS BEM Java Applets Dynamic Drive React Ember jQuery UI Bootstrap Web Components
18. @stopsatgreen W3C WHATWG
19. @stopsatgreen
20. @stopsatgreen • jQuery : querySelector(), classList • Modernizr : @supports • Sass : --custom-properties()
21. @stopsatgreen Let us make the tools we need.
22. @stopsatgreen #extendthewebforward http://extensiblewebmanifesto.org/
23. @stopsatgreen <flex-carousel> <prev-next> <show-position> <open-lightbox>
24. @stopsatgreen http://msdn.microsoft.com/library/ie/ms531426.aspx
25. @stopsatgreen
26. @stopsatgreen
27. @stopsatgreen
28. @stopsatgreen meaningful naming + modularisation + encapsulation + sharing = web components
29. @stopsatgreen HOW?
30. @stopsatgreen Custom Elements
31. @stopsatgreen <fun-times></fun-times> document.registerElement('fun-times');
32. @stopsatgreen <fun-times></fun-times> = HTMLElement <funtimes></funtimes> = HTMLUnknownElement
33. @stopsatgreen fun-times:unresolved {…}
34. @stopsatgreen proto = Object.create(HTMLElement.prototype); proto.hooray = function() {…}; document.registerElement('fun-times',
 { prototype: proto }); funTimes = document.querySelector('fun-times');
 funTimes.hooray();
35. @stopsatgreen proto = Object.create(HTMLElement.prototype); proto.createdCallback = function() {…}; document.registerElement('fun-times',
 { prototype: proto });
36. @stopsatgreen <button is="fun-times"></button> proto = Object.create(HTMLButtonElement.prototype); proto.hooray = function() {…}; document.registerElement('fun-times', { prototype: proto, extends: 'button' });
37. @stopsatgreen Shadow DOM
38. @stopsatgreen
39. @stopsatgreen
40. @stopsatgreen var root = foo.createShadowRoot();
 root.innerHTML = '<div>…</div>';
41. @stopsatgreen Templates
42. @stopsatgreen <template id="party">…</template> var party = document.getElementById('party'); var partyContent = party.content;
43. @stopsatgreen var funTimes = document.querySelector('fun-times'); var proto = Object.create(HTMLElement.prototype); proto.hooray = function() {…}; proto.createdCallback = function() { var party = document.getElementById('party'); var clone = document.importNode(party.content,true); var root = funTimes.createShadowRoot(); root.appendChild(clone); } document.registerElement('fun-times', { prototype: proto });
44. @stopsatgreen HTML Imports
45. @stopsatgreen <link rel="import" href="fun-times.htm">
46. @stopsatgreen http://leafletjs.com/
47. @stopsatgreen <leaf-map lat="33.9186805" lon="8.1198406"></leaf-map> <link rel="import" href="leaflet-map.htm">
48. @stopsatgreen But it’s not all rosy.
49. @stopsatgreen The is="" pattern. https://lists.w3.org/Archives/Public/public-webapps/2015JanMar/0206.html
50. @stopsatgreen <button is="fun-times"></button> <h1 is="h-7"></h1> <iframe is="new-button"></iframe>
51. @stopsatgreen document.registerElement('fun-times'); var funRoot = funTimes.createShadowRoot(); funRoot.innerHTML = '<button>…</button>';
52. @stopsatgreen HTML Imports have huge potential for performance problems…
53. @stopsatgreen /path/to/library.min.js
 /path/to/a/library.min.js
54. @stopsatgreen <link rel="import" href="//foo.com/btn-a.htm">
 <link rel="import" href="//bar.com/btn-b.htm">
 <link rel="import" href="//baz.com/btn-c.htm">
55. @stopsatgreen … so Firefox won’t implement.
56. @stopsatgreen WHEN?
57. @stopsatgreen Browser Custom Elements Shadow DOM HTML Imports Template Who knows? ‘Under consideration’ ✓ ✓ ✓ ✓ ✓ ✗ ✓ ✓ ✓ http://jonrimmer.github.io/are-we-componentized-yet/
58. @stopsatgreen Web Components will happen. Maybe not in this form, but the concept is solid.
59. @stopsatgreen
60. webcomponents.js (polyfills) Polymer Core Bosonic Core Elements Brick Paper Elements Elements polymer-project.org | brick.mozilla.io | bosonic.github.io | webcomponents.org Standard
61. @stopsatgreen Web Components vs. React (etc)
62. @stopsatgreen Everything Useful Useful & well-made Crap http://en.wikipedia.org/wiki/Sturgeon%27s_law
63. @stopsatgreen Sturgeon’s Law: 90% of everything is crap
64. @stopsatgreen http://addyosmani.com/first/
65. @stopsatgreen http://www.paciellogroup.com/blog/2014/09/web-components-punch-list/
66. @stopsatgreen Web Components are for you to drive the future of the web. Please drive responsibly.
67. @stopsatgreen THE END