Tests for Web 2.0 Services
Web 2.0 Services
How We Test
This site takes the view that check-lists and tests for usability and accessibility are not an ideal way to address the issue of how easy it may be to use a website or online application. A more holistic approach* is needed. However, the W3C WCAG Guidelines are "stable, referenceable technical standards" that aim to prevent many barriers to access. *See Reflections on the Development of a Holistic Approach to Web Accessibility.
Login, Signup and Other Forms
This covers all aspects of registering with a service or site, then returning to sign-in and finally to work with forms. Those who use screen readers and keyboard access need to be able to reach the forms and exit to the rest of the site. Good labelling enables users to understand the type of content required. Keyboard focus needs to be managed appropriately within form fields, particularly if the form appears in a modal window. Users should be informed of required fields and able to perceive error alerts if form submission fails. Form should also work effectively when using alternative input devices, including touch screens.
Image ALT Attributes and Text Alternative
Images need to have what is commonly known as an 'alt-tag' or text alternative, so that a screen reader user can hear an image description. Some screen readers will read the file name or some say 'image' if the attribute is omitted. The alt-tag should be appropriate for the content and succinct. Text should be accessible to text-to-speech tools and screen-readers so that it is read aloud accurately and intelligibly.
Link Target Definitions
Where links are used for menus and navigation or to send users to a different site or area on the page the text for all links needs to be understandable when used without a surrounding sentence or button. Navigation elements, such as buttons, should have the correct role assigned to them. Alternative navigation elements, such as a breadcrumb trail, sitemap or search facility are beneficial. Use of link target icons should be consistent, familiar and labelled appropriately to be fully accessible.
Logical Page Structure and Order
The layout of the contents of a web page can be set into frames rather like a picture or even a frame within a frame (an iframe) so that more information can be carried within a single page. Frames should have titles so that screen reader users know where they are in the page or which piece of content to read next. Providing a mechanism for users to skip to the main content aids navigation on content heavy sites. Navigational tags, such as ARIA live-regions can help assistive technology users identify the structure of the page. Content needs to be marked up in code in the order it will be recognised by screen reader users.
Removal of Styles
Cascading Style Sheets can be used to provide layout for many aspects within a set of web pages, without the use of tables or frames. They allow web page designers to set out the presentation for a web site separately from the content. It makes it much easier to control the main items on web pages such as navigational elements. If the structure is well done it can help accessibility by allowing the user to change colours, fonts and read the site in a linear manner. It is important to check how a site looks with and without style sheets.
For those who have sensory disabilities such as deafness or a hearing impairment and for those who may have cognitive learning disabilities offering alternatives for videos with audio, podcasts or audio files for download is essential. Increased download speeds and more use of multimedia on the web means that additional text transcripts, captioning and sign language must be considered in a way that is appropriate for the content.
Video/animations - audio descriptions
For those who have visual impairments offering alternatives for animations or videos where there are long scenes with no descriptive dialogue is essential. This is particularly true if they are an important part of the web service content. Additional text transcripts and audio descriptions can make this type of media accessible.
Appropriate use of Tables
The layout of the contents of a web page can be set in tables but this can mean that a screen reader user has to listen to what comes first as the software reads across the page from left to right. It may not read down individual columns before crossing to the next row so it is best to keep tables just for data. The order of content within the table and the use of row and column headers is important.
Tab Order Correct and Logical
When you cannot use the mouse, it is very important to have a logical order in which the main navigational elements and links appear on a webpage. It is possible to specify this order but it is best to ensure that the code for the webpage results in a correct automatic tabbing order down a page in the same way that a page would linearise without any structural elements such as style sheets, frames or tables. Additional elements such as 'skip navigation links' can make it easier for screen reader users to reach main content.
Page Functionality with Keyboard and Touch Screen
It is important that all functions can be accessed through keyboard tabbing to and then using enter or space to activate elements. If the site makes use of access keys (keyboard shortcuts), it should be possible to discover these through site documentation. Screen readers depend on navigational elements on touch screens being voiced. The gestures tend to change when a screen reader is used with double tap to activate elements and a different number of fingers being use to flip pages.
Accessibility of Text Editors
Many of the sites that allow users to contribute text, images and other multimedia also provide an editor that allows users to change the look and feel of their text as they would in a wordprocesser application. The problem is that not all editors are accessible when using a keyboard or screen reader. TinyMCE and CKEditor are both reported to be working towards or complaint with the Authoring Tool Accessibility Guidelines (ATAG). If a user cannot reach the editor with the use of the keyboard, then a plain text form should be offered.
Once a user has submitted text or an answer to a question or multiple choice items it is important that correct feedback is received to prevent confusion. There should be no time restrictions and clear methods for pausing items or returning to a page to correct an error. Labels and instructions should be provided where content requires user input or uses unfamiliar icons. Accessible help or support materials can assist the user with interacting with the content.
Contrast and Colour Check
It is important for everyone to have an enjoyable experience when reading web sites and content should have good levels of colour contrast and no distracting elements. Symbols and other items that are important for navigation can be provided in various colours, but should have other obvious differences to help those with colour deficiencies (colour blindness).
Page Integrity when Zooming
Most browsers allow text and images to be enlarged through a zoom feature or text-resize. This has become more and more useful as web developers appear to be reducing the general size of fonts used which can affect those with visual acuity difficulties and older people. Zooming can improve readability but there are times when it also affects the layout of websites.
Text size, style, blinking elements and Readability
Items that flash or blink at a certain rate can cause seizures and should be avoided. They can also be very distracting and make other elements on a page hard to read. Complex small text and serif fonts can also make text harder to read for some people with cognitive learning disabilities and specific learning differences including dyslexia. The language used needs to be understandable for all users including those who have been deaf since birth or for whom English is not their first language. The language of the page can be programmatically determined.