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@ngdoc tutorial | ||
@name 15 - Accessibility | ||
@step 15 | ||
@description | ||
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<ul doc-tutorial-nav="15"></ul> | ||
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In this step, we will learn how to fix the accessibility issues in our application. | ||
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* We will fix some issues in the templates. | ||
* We will use the [protractor-accessibility-plugin](protractor-a11y-plugin) to review the accessibility of our application when we run our e2e tests. | ||
* We will explain how to add the {@link ngAria ngAria} module to use WAI-ARIA easily if you need it in your project. | ||
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<div doc-tutorial-reset="15"></div> | ||
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## Why accessibility matters | ||
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A website or application accessible allows the users with different preferences and abilitities, to consume the content in a way that suits their needs. | ||
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* [Creating an accessible web - Access iQ](https://www.youtube.com/watch?v=47n0wEcm6JU) | ||
* [Web Accessibility](https://www.youtube.com/watch?v=bEM9Fn9aOG8) | ||
* [Google Accessibility course](https://webaccessibility.withgoogle.com/course) | ||
* [Accessibility in AngularJS and Beyond](http://marcysutton.com/slides/fluent2015/) | ||
* [Introduction to Web Accessibility](https://www.w3.org/WAI/intro/accessibility.php) | ||
* [Apps For All: Coding Accessible Web Applications](https://shop.smashingmagazine.com/products/apps-for-all) | ||
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There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more. Here's one more article that was written in response to Angular a11y: https://www.smashingmagazine.com/2015/05/client-rendered-accessibility/ |
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## WAI-ARIA | ||
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WAI-ARIA (_the Accessible Rich Internet Applications Suite_) gives you the ability to reclassify and otherwise augment the perceived meaning (or semantics) of your HTML. | ||
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Currently certain functionality used in Web sites is not available to some users with disabilities, especially people who rely on screen readers and people who cannot use a mouse. WAI-ARIA addresses these accessibility challenges, for example, by defining new ways for functionality to be provided to assistive technology. With WAI-ARIA, developers can make advanced Web applications accessible and usable to people with disabilities. | ||
There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more. I would mention that ARIA is a standard set of attributes used to fill accessibility support gaps in custom HTML elements and SVG. |
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AngularJS has a module called {@link ngAria ngAria} to help developers to add some WAI-ARIA attributes easily in your application. | ||
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## Main accessibility issues in the application | ||
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If you make a review of the accessibility of the application you will find some issues: | ||
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* Lack of information about the current results when the user interacts with the filters. | ||
* Lack of labels elements in the search and order filters in the Phone list. | ||
* Lack of headers elements to help the user to navigate throw the content of the page. | ||
* In the Phone detail, the user can't access via keyboard over the thumbnails images. | ||
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In the next sections we are going to show you, how to fix some of these issues to make the application accessible. | ||
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To help us, we will install the [protractor-a11y-plugin] plugin to check potential issues in the application. | ||
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## How to inform the user that _something_ is happening | ||
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Today, is very common to find applications or webpages where the user make some interaction with an element and obtains and inmediate reply to the action. | ||
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The problem is that in most of the cases this action is only reported in a way that you need to see it in your screen but if a user is navigating with a screenreader like [JAWS](http://www.freedomscientific.com/Products/Blindness/JAWS), [NVDA](http://www.nvaccess.org/) or [ChromeVox](http://www.chromevox.com/), this information never won't be accessible. | ||
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When the user is searching or filtering mobiles in the application, the list updates automatically. It is mandatory that user knows, in some way, the result after the search or order action. | ||
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To fix this, we add two directives to inform the user how many items are know in the list after search or order them. This directive will fill an element in our page to tell the user how many elements are after the action. | ||
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<br /> | ||
**`app/phone-list/phone-list-template.html`:** | ||
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```html | ||
<div> | ||
<label for="search">Search:</label> | ||
<input id="search" ng-model="$ctrl.query" ng-model-options="{ debounce: 300 }"> | ||
</div> | ||
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<div class="aria-status" aria-live="assertive" aria-atomic="true"></div> | ||
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... | ||
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<div class="aria-status-sort" aria-live="assertive" aria-atomic="true"></div> | ||
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``` | ||
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The new element is a _region live_. It means that every time this region is updated, it will inform the user about its content. | ||
There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more. *live region |
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In order to update the information correctly, it is neccesary to add a _`debounce`_ option to the model. | ||
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Please note that now the inputs are associated with theirs labels using `label` elements. | ||
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The directives are based on an idea of [Marcy Sutton](http://marcysutton.com/slides/fluent2015/) about how to add accessibility in the AngularJS applications. | ||
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### How to use the directives | ||
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<br /> | ||
**`app/phone-list/phone-list-template.html`:** | ||
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```html | ||
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... | ||
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<div> | ||
<label for="order">Sort by:</label> | ||
<select inform-order id="order" ng-model="$ctrl.orderProp"> | ||
<option value="name">Alphabetical</option> | ||
<option value="age">Newest</option> | ||
</select> | ||
</div> | ||
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... | ||
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<ul result-list class="phones"> | ||
<li ng-repeat="phone in filtered = ($ctrl.phones | filter:$ctrl.query | orderBy:$ctrl.orderProp)" | ||
class="thumbnail phone-list-item"> | ||
<a href="#!/phones/{{phone.id}}" class="thumb"> | ||
<img ng-src="{{phone.imageUrl}}" alt="{{phone.name}}" /> | ||
</a> | ||
<a href="#!/phones/{{phone.id}}">{{phone.name}}</a> | ||
<p>{{phone.snippet}}</p> | ||
</li> | ||
</ul> | ||
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``` | ||
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<br /> | ||
**`app/index.html`:** | ||
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```html | ||
... | ||
<script src="phone-list/phone-list.directive.js"></script> | ||
... | ||
``` | ||
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<br /> | ||
**`app/phone-list/phone-list.directive.js`:** | ||
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```js | ||
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'use strict'; | ||
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/* Directives */ | ||
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angular. | ||
module('phoneList'). | ||
directive('resultList', [function () { | ||
var ariaStatus = document.querySelector('.aria-status'); | ||
return { | ||
restrict: 'A', | ||
link: function ($scope) { | ||
$scope.$watch('filtered.length', function (length) { | ||
if(length === 1) { | ||
ariaStatus.innerHTML = length + ' item found'; | ||
} else if(length > 1) { | ||
ariaStatus.innerHTML = length + ' items found'; | ||
} else { | ||
ariaStatus.innerHTML = 'No items found'; | ||
} | ||
}); | ||
} | ||
} | ||
} | ||
]). | ||
directive('informOrder', [function () { | ||
var ariaStatusSort = document.querySelector('.aria-status-sort'); | ||
return { | ||
restrict: 'A', | ||
link: function ($scope) { | ||
$scope.$watch('$ctrl.orderProp', function (order) { | ||
if(order === 'age') { | ||
ariaStatusSort.innerHTML = 'Items filter by newest' | ||
} else { | ||
ariaStatusSort.innerHTML = 'Items filter by alphabetical order' | ||
} | ||
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}); | ||
} | ||
} | ||
} | ||
]); | ||
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``` | ||
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## Using the keyboard | ||
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The current detail of a phone prevents a user to use a keyboard to navigate for over each thumbnail image. It is very important due to accessibility that all the actions and information are available via keyboard too. For example, lightboxes, carousels, slides, etc. | ||
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_Tip_: Try to navigate over the application using only the _TAB_ key. You will discover that some actions can't be accessed nor the focus on some elements. | ||
There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more. So, how are we solving this? There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more. I've added how to fix this problem (adding a button element). For this reason, and after check again the project, the |
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<br /> | ||
**`app/phone-detail/phone-detail.template.html`:** | ||
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```html | ||
... | ||
<ul class="phone-thumbs"> | ||
<li ng-repeat="img in $ctrl.phone.images"> | ||
<button type="button" aria-label="view enlarge version of the image" ng-click="$ctrl.setImage(img)"><img ng-src="{{img}}" alt="" /></button> | ||
</li> | ||
</ul> | ||
... | ||
``` | ||
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To fix this issue, we add a `button` element, wrapping the image to allow the user to access the content via keyboard. | ||
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Why we are using a `button` element instead of an `a` element? It is more correct to use buttons elements to call actions like show content, hidden content or similar. | ||
There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more. Because it does not navigate to a new page or resource. |
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## How to use the `ngAria` module | ||
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The `ngAria` module provides support for common WAI-ARIA attributes that convey state or semantic information about the application for users of assistive technologies, such as screen readers. | ||
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### Dependencies | ||
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The `ngAria` module, is distributed separately from the core Angular framework. | ||
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Since we are using [Bower][bower] to install client-side dependencies, this step updates the | ||
`bower.json` configuration file to include the new dependencies: | ||
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<br /> | ||
**`bower.json`:** | ||
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``` | ||
{ | ||
"name": "angular-phonecat", | ||
"description": "A starter project for AngularJS", | ||
"version": "0.0.0", | ||
"homepage": "https://github.com/angular/angular-phonecat", | ||
"license": "MIT", | ||
"private": true, | ||
"dependencies": { | ||
"angular": "1.5.x", | ||
"angular-animate": "1.5.x", | ||
"angular-aria": "1.5.x", | ||
"angular-mocks": "1.5.x", | ||
"angular-resource": "1.5.x", | ||
"angular-route": "1.5.x", | ||
"bootstrap": "3.3.x", | ||
"jquery": "2.2.x" | ||
} | ||
} | ||
``` | ||
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* `"angular-aria": "1.5.x"` tells bower to install a version of the angular-aria module that | ||
is compatible with version 1.5.x of Angular. | ||
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We need to add a dependency on `ngAria` to our main module first: | ||
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<br /> | ||
**`app/app.module.js`:** | ||
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```js | ||
angular. | ||
module('phonecatApp', [ | ||
... | ||
'ngAria', | ||
... | ||
]); | ||
``` | ||
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In order to enable the module, we need to update `index.html`, loading the necessary dependencies | ||
(**angular-aria.js**) that contain JavaScript code. | ||
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The WAI-ARIA module, {@link ngAria ngAria}, contains the code necessary to help you to add WAI-ARIA attributes in your application. | ||
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<br /> | ||
**`app/index.html`:** | ||
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```html | ||
... | ||
<!-- Adds WAI-ARIA module in AngularJS --> | ||
<script src="bower_components/angular-aria/angular-aria.js"></script> | ||
... | ||
``` | ||
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## How to run the e2e tests using the Protractor accessibility plugin | ||
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### Dependencies | ||
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To install the [protractor-a11y-plugin], we can add the plugin into the `devDependencies` section in the `package.json` file, | ||
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**`package.json`:** | ||
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``` | ||
{ | ||
"devDependencies": { | ||
"bower": "^1.7.7", | ||
"http-server": "^0.9.0", | ||
"jasmine-core": "^2.4.1", | ||
"karma": "^0.13.22", | ||
"karma-chrome-launcher": "^0.2.3", | ||
"karma-firefox-launcher": "^0.1.7", | ||
"karma-jasmine": "^0.3.8", | ||
"protractor": "^3.2.2", | ||
"protractor-accessibility-plugin": "^0.1.1", | ||
"shelljs": "^0.6.0" | ||
} | ||
} | ||
``` | ||
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Now, we must tell bower to download and install these dependencies. | ||
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``` | ||
npm install | ||
``` | ||
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<div class="alert alert-info"> | ||
**Note:** If you have bower installed globally, you can run `bower install`, but for this project | ||
we have preconfigured `npm install` to run bower for us. | ||
</div> | ||
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<div class="alert alert-warning"> | ||
**Warning:** If a new version of Angular has been released since you last ran `npm install`, then | ||
you may have a problem with the `bower install` due to a conflict between the versions of | ||
angular.js that need to be installed. If you run into this issue, simply delete your | ||
`app/bower_components` directory and then run `npm install`. | ||
</div> | ||
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Once the plugin is installed, we have to modify the `protractor.conf.js` file to inform Protractor to use this plugin too. | ||
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**`protractor.conf.js`:** | ||
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``` | ||
plugins: [{ | ||
chromeA11YDevTools: { | ||
treatWarningsAsFailures: true | ||
}, | ||
package: 'protractor-accessibility-plugin' | ||
}] | ||
``` | ||
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After that, every time we run the e2e tests, Protractor will review the accessibility of your application using the [Accessibility Developer Tools](https://github.com/GoogleChrome/accessibility-developer-tools). | ||
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# Summary | ||
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Our application is now accessible, thanks to these small changes. | ||
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There you have it! We have created a web application in a relatively short amount of time. In the | ||
{@link the_end closing notes} we will cover where to go from here. | ||
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<ul doc-tutorial-nav="15"></ul> | ||
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[bower]: http://bower.io/ | ||
[protractor-a11y-plugin]: https://github.com/angular/protractor-accessibility-plugin |
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Could you add a paragraph on what is "accessibility" and "aria" and how it affects people. Just a brief summary and then list the links for more info.
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ok, I'm on it.
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I've added some definitions.