html5 and friends - standards>next manchester 24.11.2010
TRANSCRIPT
HTML5 and friends
Patrick H. Lauke / standards>next / Manchester / 24 November 2010
CONTEXTUALISING THE NEW TECHNOLOGIES
Web Evangelist at Opera
...should I use HTML5 today?
"there is already a lot of excitement for HTML5, but it’s a little too early to deploy it because we’re running into interoperability issues."
Philippe Le Hegaret, W3C interaction domain leader
blogs.techrepublic.com.com/hiner/?p=6369
http://www.flickr.com/photos/24374884@N08/4603715307/
HTML5…without the hype?
A brief history of HTML5
1999 HTML 4.012000 XHTML 1.0
2004 W3C focus on XHTML 2.0…the future is XML-based!
http://www.flickr.com/photos/craiga/17071467/
WHATWGWeb Hypertext Application Technology Working Group
2007 W3C HTML5 WG
“...extending the language to better support Web applications [...] This puts HTML in direct competition with other technologies[...] , in particular Flash and Silverlight.”
Ian Hickson, Editor of HTML5http://lists.w3.org/Archives/Public/public-html/2009Jan/0215.html
HTML5 does not replace HTML 4.01 / XHTML 1.0
HTML5 has more bling!
HTML5 specification forbrowser developers
(how to interpret markup/code – no more reverse engineering)
for authors: HTML5 differences from HTML4http://www.w3.org/TR/html5-diff/
1. syntax/semantic2. forms3. multimedia
1. syntax/semantic2. forms3. multimedia
HTML5 standardisescurrent browser behaviour
(e.g. “relaxed” coding rules)
the dirty secret of the doctype
XHTML 1.0<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
HTML5<!DOCTYPE html>
<meta charset=”utf-8” />
<meta charset=utf-8>
<MeTa CHarSet=utf-8>
<style type=”text/css”></style>
<script type=”text/javascript”></script>
<style type=”text/css”></style>
<script type=”text/javascript”></script>
<!doctype html><title>Minimal HTML5</title>
new elemente for more accurate semantics
Top 20 class names1. footer 11. button
2. menu 12. main
3. style1 13. style3
4. msonormal 14. small
5. text 15. nav
6. content 16. clear
7. title 17. search
8. style2 18. style4
9. header 19. logo
10. copyright 20. body
http://devfiles.myopera.com/articles/572/classlist-url.htm
Top 20 id names1. footer 11. search
2. content 12. nav
3. header 13. wrapper
4. logo 14. top
5. container 15. table2
6. main 16. layer2
7. table1 17. sidebar
8. menu 18. image1
9. layer1 19. banner
10. autonumber1 20. navigation
http://devfiles.myopera.com/articles/572/idlist-url.htm
unambiguous and machine readable...e.g. screenreaders?
new and old browsers “support” these(although some need a little extra help)
header, footer, … { display: block; }
Internet Explorer <9 needs extra training wheels
document.createElement('header');document.createElement('footer');…
http://html5doctor.com/how-to-get-html5-working-in-ie-and-firefox-2
1. syntax/semantics2. forms3. multimedia
improved form elementsbecause the web is more interactive
rich form elements – without faking them in JS
<input type=”date”><input type=”time”><input type=”month”><input type=”week”><input type=”datetime” … ><input type=”range”><input type=”number”>
<input type=”file” multiple>
<input … autofocus><input … autocomplete>
types und attributes withbuilt-in validation<input … required><input type=”tel”><input type=”email”><input type=”url”><input … pattern="[a-z]{3}[0-9]{3}">
1. syntax/semantics2. forms3. multimedia
making your site Fonzie compliant...
<video>
Adobe Flash currently most commonvideo delivery mechanism
<object width="425" height="344"><param name="movie"
value="http://www.youtube.com/v/9sEI1AUFJKw&hl=en&fs=1&"></param>
<param name="allowFullScreen" value="true"></param>
<param name="allowscriptaccess" value="always"></param>
<embed src="http://www.youtube.com/v/9sEI1AUFJKw&hl=en&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>
<video src="video.webm" controls autoplay loop preload poster="poster.jpg" width="320" height="240"> <a href="video.webm">Download movie</a></video>
video as native object
● behaves like any other HTML element● keyboard accessibility out-of-the-box
powerful (simple) API
controlling <video> with JavaScript
var v = document.getElementById('player');
v.play();v.pause();v.volume = … ;v.currentTime = … ;…
events fired by <video>
var v = document.getElementById('player');
v.addEventListener('loadeddata', function() { … }, true)v.addEventListener('play', function() { … }, true)v.addEventListener('pause', function() { … }, true)v.addEventListener('timeupdate', function() { … }, true)v.addEventListener('ended', function() { … }, true)…
video formatsthe big debate?
HTML5 does not specify video container/codec
(same as with images in HTML 4?)
MP4 / H.264
ubiquitous, patent encumbered, licensing/royalties
Ogg Theora
free and open, no licensing feesnot many tools for it, not web optimised
WebM / VP8
open and royalty-free, web-optimisedsupport by hardware and software vendors
providing multiple sources<video controls autoplay poster="…" width="…" height="…">
<source src="movie.mp4" type="video/mp4" /><source src="movie.webm" type="video/webm" /><source src="movie.ogv" type="video/ogg" /><!-- fallback content -->
</video>
flash fallback for older browsershttp://camendesign.com/code/video_for_everybody
<video controls autoplay poster="…" width="…" height="…"><source src="movie.mp4" type="video/mp4" /><source src="movie.webm" type="video/webm" /><source src="movie.ogv" type="video/ogg" />
<object width="…" height="…" type="application/x-shockwave-flash" data="player.swf">
<param name="movie" value="player.swf" /><param name="flashvars" value=" … file=movie.mp4" /><!-- fallback content -->
</object>
</video>
<audio>
audio...exactly the same as video
<audio src=”music.mp3” controls autoplay … ></audio>
<audio controls autoplay><source src="music.mp3" type="audio/mpeg" /><source src="music.oga" type="audio/ogg" /><!-- fallback content -->
</audio>
formats: MP3 vs Ogg Vorbis (vs WAV)
<canvas>
canvas = “scriptable images”
<canvas width="…" height="…"></canvas>
canvas has standard API methods for drawing
ctx = canvas.getContext("2d");
ctx.fillRect(x, y, width, height);ctx.beginPath();ctx.moveTo(x, y);ctx.lineTo(x, y);ctx.bezierCurveTo(x1, y1, x2, y2, c1, c2);
ctx.drawImage(…);
canvas accessibility?
video, audio and canvason all devices without plugins
(Java / Flash / Silverlight not ubiquitous)
HTML5 (and friends) haslots more APIs for developers
(for powerful client-side apps)
geolocationnavigator.geolocation.getCurrentPosition(success, error);navigator.geolocation.watchCurrentPosition(success, error);
function success(position) {/* where's Wally? */var lat = position.coords.latitude;var long = position.coords.longitude;...
}
offline detection...
window.addEventListener('online', function(){ … }, true);window.addEventListener('offline', function(){ … }, true);
and application cache<html manifest=”blah.manifest”>
CACHE MANIFEST# send this with correct text/cache-manifest MIMEimages/sprites.pngscripts/common.jsscripts/jquery.jsstyles/global.cssdata.xml
and much more...
is it all safe to use, right now?
don't do browser sniffing
http://www.flickr.com/photos/timdorr/2096272747/
feature-detectionprogressive enhancement, graceful degradation
http://diveintohtml5.org/everything.html
feature-detection for audio/video
if (!!document.createElement('video').canPlayType;) { … }
if (!!document.createElement('audio').canPlayType;) { … }
patching older browsersgithub.com/Modernizr/Modernizr/wiki/HTML5-Cross-browser-Polyfills
HTML5 as Flashkiller?
not a question ofHTML5 replacing Flash...
giving developers a choice!
...should I use HTML5 today?
“The future is already here – it's just not very evenly distributed”
William Gibson
www.opera.com/developerpeople.opera.com/patrickl/presentations/standards-next_24.11.2010/standards-next_24.11.2010.pdf