Page-level accessibility using WAI-ARIA roles
The Pega 7 Platform supports accessibility through the use of WAI-ARIA (Web Accessibility Initiative Accessible Rich Internet Applications) roles. WAI-ARIA roles are a World Wide Web Consortium (W3C) ontology that specifies roles, states, or properties for a user interface element. WAI-ARIA roles provide semantic information about features, structures, and behaviors that assistive technologies use to convey information to users. A screen reader or other assistive technology can parse the information provided by a WAI-ARIA role and provide alternative navigation to the user.
The role that is assigned to a user interface element does not affect the performance or functionality of the product. The role communicates what the element is or does and can be read and interpreted by the assistive technology. You can read more about the taxonomy of roles and their specific uses by visiting the World Wide Web Consortium at w3c.org and searching for content that is related to WAI-ARIA roles.
The Pega 7 Platform uses three WAI-ARIA role types to support accessibility. Within these three types there are roles, which are the specific descriptor to be assigned to a user interface element.
- A region of the page to which the user might want quick access
- Is purpose-specific, relating to navigation, search, or consuming content
- Examples include: banner, form, navigation, and search
- Document structure
- Describe the structure of the page content
- Typically are not interactive
- Includes elements such as row or column headings, notes, and presentations
- An interactive interface object
- Map to standard features in accessibility APIs
- When a user navigates to a widget, assistive technologies intercept keyboard events and pass them through the web application to the widget.
Main content area
A main content area is a WAI-ARIA role for the most prominent screen area in which the user consumes content or interacts with an application. When the user tabs through the interface, a "Skip to main content" link is displayed. The user can then press the Enter key to go directly to the main content area.
The primary benefit of providing a link to the main content area is that the user can bypass everything between the top of the page and the main content area. This shortcut saves the user from having to tab through extensive menus or extraneous content.
In a Pega 7 Platform application, several UI elements are assigned ARIA roles by default or by configuration.
- Dynamic container
- When added to a user interface, the dynamic container is by default marked as the main content area.
- The ARIA role for a dynamic container cannot be altered in development.
- Dynamic layout
- Can be assigned the role of main content area, but the dynamic layout must be configured as the main content area
- Can be assigned one of several ARIA roles depending on function
- Screen layout
- The top, bottom, left, right, and center areas of a screen layout have ARIA roles that are assigned by default.
- The center area of the screen layout is marked as the main content area.
When a dynamic container, dynamic layout, or screen layout uses the main content ARIA role, users tabbing through the interface are first given links to skip to content areas given certain roles. These links give users the option of skipping to the main content, search, or navigation areas of the screen.
Content links in a portal allow the user to tab to an area with an assigned ARIA role