Colin Clark Accessible U Is With J Query And Infusion[1]

Building Accessible User Interfaces with jQuery and Fluid Infusion Colin Clark, Fluid Project Technical Lead, Adaptive Technology Resource Centre Monday, September 14, 2009

Topics We’ll Cover • The Fluid community • Introducing Infusion • Developing accessible JavaScript • Infusion’s Architecture • Techniques for portals, mashups, CMS’s • Where we’re headed Monday, September 14, 2009

Fluid... http://ﬂuidproject.org • Is an open source community of • Designers • Developers • Accessibility experts • Helps other open communities • Consists of universities, museums and individuals Monday, September 14, 2009

What We Do • Offer design advice and resources • Contribute to other communities: • jQuery UI • Dojo • W3C Accessibility • Build Infusion, our JavaScript application framework Monday, September 14, 2009

Introducing http://ﬂuidproject.org/products/infusion/ Monday, September 14, 2009

World, Meet Infusion • Application framework built on top of jQuery • The culmination of our work helping others • Designed for usability and accessibility • Open architecture: everything is conﬁgurable Monday, September 14, 2009

What’s in Infusion? • A development framework for building apps • UI components you can reuse and adapt • Lightweight CSS framework for styling • Accessibility tools and plugins for jQuery Monday, September 14, 2009

Building Great UIs Is Hard • Your code gets unruly as it grows • UIs are hard to reuse or repurpose • Design change requires big code change • Accessibility is confusing • Combining different code/libraries doesn’t always work Monday, September 14, 2009

Flexible User Interfaces Infusion is an application framework designed to provide unprecedented ﬂexibility while preserving interoperability. Monday, September 14, 2009

Types of JavaScript Tools • Foundational Toolkits • Application Frameworks ... compare and contrast Monday, September 14, 2009

Foundational toolkits • Totally presentation focused • DOM manipulation • Event binding jQuery • Ajax Prototype Dojo core Monday, September 14, 2009

Application frameworks • Model notiﬁcations “something changed here” • Views to help keep your presentational code clean • Data binding to sync the display with your model SproutCore Dojo/Dijit/ Dojox Cappuccino Monday, September 14, 2009

Infusion is Different • Accessibility baked right in • Carefully designed interactions • Markup is in your control • Not the same old MVC • Supports portals, mashups and CMS’s Monday, September 14, 2009

Deeply Accessible Monday, September 14, 2009

What is Accessibility? Monday, September 14, 2009

A New Definition • Accessibility is the ability of the system to accommodate the needs of the user • Disability is the mismatch between the user and the interface provided • We all experience disability • Accessible software = better software Monday, September 14, 2009

Assistive Technologies • Present and control the user interface in different ways • Not just screen readers! • Use built-in operating system APIs to understand the user interface Screen readers Screen magniﬁers On-screen keyboards Monday, September 14, 2009

DHTML: A New Can of Worms • Shift from documents to applications • Familiar a11y techniques aren’t enough • Most DHTML is completely inaccessible • New techniques are still being ﬁgured out Monday, September 14, 2009

The Problem • Custom widgets often look, but don’t act, like their counterparts on the desktop • HTML provides only simple semantics • Not enough information for ATs • Dynamic updates require new design strategies to be accessible Monday, September 14, 2009

The Solution • Describe user interfaces with ARIA • Add consistent keyboard controls • Provide ﬂexible styling and presentation Monday, September 14, 2009

Supporting Assistive Technology Monday, September 14, 2009

Opaque Markup // These are tabs. How would you know? <ol> <li><a href=”#cats”>Cats</a></li> <li><a href=”#dogs”>Dogs</a></li> <li><a href=”#gators”>Gators</a></li> </ol> <div> <div id=”cats”>Cats meow.</div> <div id=”dogs”>Dogs bark.</div> <div id=”gators”>Gators bite.</div> </div> Monday, September 14, 2009

Opaque Markup: Tabs Monday, September 14, 2009

ARIA • Accessible Rich Internet Applications • W3C speciﬁcation in the works • Fills the semantic gaps in HTML • Roles, states, and properties • Live regions Monday, September 14, 2009

Roles, States, Properties • Roles describe widgets not present in HTML 4 • slider, menubar, tab, dialog • Properties describe characteristics: • draggable, hasPopup, required • States describe what’s happening: • busy, disabled, selected, hidden Monday, September 14, 2009

Using ARIA // Now *these* are Tabs! <ol id=”animalTabs” role=”tablist” tabindex=”0”>   <li role=”tab”><a href=”#” tabindex=”-1”>Cats</a></li> <li role=”tab”><a href=”#” tabindex=”-1”>Dogs</a></li> <li role=”tab”><a href=”#” tabindex=”-1”>Gators</a></li> </ol> <div id=”panels”> <div role=”tabpanel” aria-labelledby=”cats”>Cats meow.</div> <div role=”tabpanel” aria-labelledby=”dogs”>Dogs bark.</div> <div role=”tabpanel” aria-labelledby=”gators”>Gators bite.</div> </div> Monday, September 14, 2009

Adding ARIA in Code // Identify the container as a list of tabs. tabContainer.attr("role", "tablist"); // Give each tab the "tab" role. tabs.attr("role", "tab"); // Give each panel the appropriate role, panels.attr("role", "tabpanel"); panels.each(function (idx, panel) { var tabForPanel = that.tabs.eq(idx); // Relate the panel to the tab that labels it. $(panel).attr("aria-labelledby", tabForPanel[0].id); }); Monday, September 14, 2009

Keyboard Accessibility Monday, September 14, 2009

Keyboard Navigation • Everything that works with the mouse should work with the keyboard • ... but not always in the same way • Support familiar conventions http://dev.aol.com/dhtml_style_guide Monday, September 14, 2009

Keyboard Conventions • Tab key focuses the control or widget • Arrow keys select an item • Enter or Spacebar activate an item • Tab is handled by the browser. For the rest, you need to write code. A lot of code. Monday, September 14, 2009

Keyboard a11y: Tabs Monday, September 14, 2009

Tabindex examples  <ol id=”animalTabs” tabindex=”0”>   <li id=”tab1”> <a href=”#cats” tabindex=”-1”>Cats</a> </li> <li id=”tab2”> <a href=”#cats” tabindex=”-1”>Dogs</a> </li> <li id=”tab3”> <a href=”#cats” tabindex=”-1”>Alligators</a> </li> </ol> Monday, September 14, 2009

Making Things Tabbable • Tabindex varies subtly across browsers • jquery.attr() normalizes it as of 1.3 • For all the gory details: http://fluidproject.org/blog/2008/01/09/ getting-setting-and-removing-tabindex-values-with-javascript/ // Make the tablist accessible with the Tab key. tabContainer.attr("tabindex", "0"); // And take the anchors out of the Tab order. $(“a”, tabs).attr("tabindex", "-1"); Monday, September 14, 2009

Adding the Arrow Keys // Make each tab accessible with the left and right arrow keys. tabContainer.fluid("selectable", { selectableSelector: that.options.selectors.tabs, direction: fluid.a11y.orientation.HORIZONTAL, onSelect: function (tab) { $(tab).addClass(that.options.styles.highlighted); }, onUnselect: function (tab) { $(tab).removeClass(that.options.styles.highlighted); } }); Monday, September 14, 2009

Making Them Activatable // Make each tab activatable with Spacebar and Enter. tabs.fluid("activatable", function (evt) { // Your handler code here. Maybe the same as .click()? }); Monday, September 14, 2009

Documentation • Tutorial: http://wiki.fluidproject.org/display/fluid/Keyboard+Accessibility+Tutorial • API Reference: http://wiki.fluidproject.org/display/fluid/Keyboard+Accessibility+Plugin+API Monday, September 14, 2009

Infusion Goes Deeper • jQuery Keyboard Navigation Plugin • ARIA everywhere • Everything is highly adaptable and ﬂexible • UI Options and the Fluid Skinning System: • Users can customize their environment Monday, September 14, 2009

UI Options • One size doesn’t ﬁt all • Allows users to customize your app: • layout • styling • navigation • Uses FSS by default; can be conﬁgured to work with your own classes Monday, September 14, 2009

UI Options & FSS Monday, September 14, 2009

CSS Frameworks “If you’re going to use a framework, it should be yours; one that you’ve created. You can look at existing frameworks for ideas and hack at it. But the professionals in this room are not well served by picking up a framework and using it as-is.” - Eric Meyer Monday, September 14, 2009

Fluid Skinning System • FSS is built to be hacked on • Provides a core set of building blocks • Reset, text, layouts, themes • Namespaced: no conﬂicts with your stuff • Themes for better legibility & readability http://wiki.ﬂuidproject.org/x/96M7 Monday, September 14, 2009

Open Architecture Monday, September 14, 2009

Markup Agnosticism • HTML is so fundamental to Web UIs • Others lock away markup in a black box • Markup should be totally free to edit, adapt, or replace • Libraries shouldn’t bake in assumptions about your markup • Unobtrusiveness everywhere Monday, September 14, 2009

Handling Markup: Dojo <div class="dijitDialog" tabindex="-1" waiRole="dialog" waiState="labelledby-${id}_title"> <div dojoAttachPoint="titleBar" class="dijitDialogTitleBar"> <span dojoAttachPoint="titleNode" class="dijitDialogTitle" id="${id}_title"></span> <span dojoAttachPoint="closeButtonNode" class="dijitDialogCloseIcon" dojoAttachEvent="onclick: onCancel, onmouseenter: _onCloseEnter, onmouseleave: _onCloseLeave" title="${buttonCancel}"> <span dojoAttachPoint="closeText" class="closeText" title="${buttonCancel}">x</span> </span> </div> <div dojoAttachPoint="containerNode" class="dijitDialogPaneContent"></div> </div> Monday, September 14, 2009

Handling Markup: jQuery UI Monday, September 14, 2009

Handling Markup: Infusion fluid.defaults("fluid.fileQueueView", { selectors: { fileRows: ".flc-uploader-file", fileName: ".flc-uploader-file-name", fileSize: ".flc-uploader-file-size", fileIconBtn: ".flc-uploader-file-action", errorText: ".flc-uploader-file-error" }, Monday, September 14, 2009

Components “Components suck. Apps built with components look like it” • Infusion components aren’t black boxes • Fundamentally adaptable: • Change the markup • Restyle with CSS • Add/replace actual behaviour • Everything is super-loosely coupled Monday, September 14, 2009

Component Families: Reorderer lists images layouts Infusion components come in families Monday, September 14, 2009

More Components Uploader Inline Edit Pager Monday, September 14, 2009

Model, View... but not Controller • MVC is a given in most framework • JavaScript’s functional idioms offer alternatives (hint: events) • Infusion has no controller layer at all • ... and none of the classical inheritance cruft that usually goes with it Monday, September 14, 2009

Traditional MVC Model n atio oti c State Query State Change ge N n Cha View Selection View Controller User Gestures Monday, September 14, 2009

The Problem with Controllers • Controllers are the least deﬁned • What’s “glue?” • Always referred to as the non-reusable part • MVC has been warped over the decades • The framework should take care of the glue Monday, September 14, 2009

Infusion Models & Views Model • Controller is replaced by events Change Noti cation • Reads to the model are transparent • State changes and notiﬁcation are just events State Query State Change • Transparent architecture: you can use View the same events we use Framework Monday, September 14, 2009

Plain Old Models • M is the most important thing in your app • Data needs to travel seamlessly between client and server • Most toolkits force a model to extend some base class or particular structure In Infusion, models are just plain old JSON Monday, September 14, 2009

Playing Nice With Others Monday, September 14, 2009

Portals, Mashups, and CMS’s • These days, diverse code and markup coexists • Most JavaScript is written as if it owns the whole browser • As you combine stuff, things can break • Namespacing and privacy is essential Monday, September 14, 2009

Writing Collision-Free JavaScript • Put code in a unique namespace • Use closures for privacy • Support more than one on the page • Scope all variables to an instance • Avoid hard-baking ID selectors • Constrain selectors within a speciﬁc element Monday, September 14, 2009

Keeping it to Ourselves • Infusion takes namespacing seriously • We won’t steal your names • Components are carefully scoped • We won’t accidently grab the wrong stuff • Infusion doesn’t expect control of the page Monday, September 14, 2009

Tying it All Together • Infusion helps you with accessibility • Components you can really work with • Simple structure so your code can grow • Totally transparent, event-driven design • Markup and models are under your control • No inheritance or controller cruft Monday, September 14, 2009

Where We’re Going Monday, September 14, 2009

Infusion Next Steps • Infusion 1.2 coming in October: • New lightweight Inversion of Control • Data Grid and reworked Pager components • Lots of bug ﬁxes • New demos portal with example code • Screencasts Monday, September 14, 2009

Fluid Engage • Open source collaboration with museums • Visitor engagement: learn and contribute • Use phones visitors bring into the museum • Mobile apps and in-gallery kiosks • All built with open source Web technology Monday, September 14, 2009

Our Mobile Approach • No hard intrusions on your content • Don’t subvert good Web idioms • Your choice: native-like or webbish Monday, September 14, 2009

Infusion Mobile • mFSS: themes for iPhone, Android, more • ScreenNavigator: unobtrusive mobile navigation • Components designed for the mobile Web Monday, September 14, 2009

Kettle: Server-side JS • Built on top of the JSGI server spec • Don’t need lots of new APIs on server • Envjs provides a full browser • Infusion as application framework • Choose where markup gets rendered • Natural, familiardesigners for Web developers and environment Monday, September 14, 2009

Wrapping Up • Tools for everyone: • ARIA • Dojo • jQuery • Infusion • Give Infusion a try and let us know • We’re a friendly community! Monday, September 14, 2009

Wrapping Up Please ﬁll out an evaluation. Monday, September 14, 2009

Questions? http://ﬂuidproject.org Monday, September 14, 2009

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Colin Clark Accessible U Is With J Query And Infusion[1]

by Ajax Experience 2009 on Sep 14, 2009

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