- HTML5 ACCESSIBILITY SCREEN READER SOFTWARE
- HTML5 ACCESSIBILITY SCREEN READER PLUS
- HTML5 ACCESSIBILITY SCREEN READER MAC
- HTML5 ACCESSIBILITY SCREEN READER WINDOWS
When it was realized that the hierarchical DOM structure mirrored the Accessibility Tree structure, in order to propagate events upward to ancestors, it became clear that browsers could leverage the same technique using pertinent Roles and States to map specific control types and their children to the Accessibility API on the hosting platform, as long as the semantic hierarchy and parent/child Roles were correctly applied in the DOM. This object structure is now what is referred to as the Accessibility Tree.
This was when the Accessibility API was bound to the platform object tree, which first occurred when Microsoft implemented OLE Accessibility in 1995 later to be renamed MSAA (Microsoft Active Accessibility). Thus allowing applications to manage child objects more effectively, in order to process mouse and keyboard events within the context of the same structure. The Accessibility API used this hierarchy to determine context, such as the number of child objects matching a specific Role.Īs desktop applications became more complex, they started to utilize object trees, instead of relying solely on window handles as they had previously. This allowed desktop applications to have containers that managed their children, such as Listboxes with child Option objects.
HTML5 ACCESSIBILITY SCREEN READER WINDOWS
The reason being, that Windows applications needed to be able to propagate mouse and keyboard events upward from an object to its ancestors. Originally, the Accessibility API on native platforms leveraged the window tree hierarchy.
To put things into perspective, it is helpful to understand the foundations of the Accessibility Tree and ARIA. Which allows access to the Accessibility Tree objects using the MSAA and UIA maps. One such for Windows OS users is Active Accessibility Object Inspector:Īnother for OS X and iOS, is Accessibility Inspector:īlind developers who use JAWS For Windows can utilize a JAWS script called BX (developed by Doug Lee):
HTML5 ACCESSIBILITY SCREEN READER SOFTWARE
There are software utilities that make it possible to traverse these Accessibility Tree objects, in order to observe the various properties and states as they change. Screen readers for example use the accessible Name of a Checkbox object to convey its name, the Role to convey the control type, the State to convey whether it is focused or checked, and so on every time a user interacts with this particular control.
HTML5 ACCESSIBILITY SCREEN READER PLUS
The Accessibility Tree is a hierarchical construct of objects that include accessible names and descriptions, plus supporting states and properties, which Assistive Technologies can interface with to enhance accessibility. When a control such as this, or of any other type, is rendered as part of the Graphical User Interface (GUI), the control and all of its public properties and states, is included in the Accessibility Tree. The Microsoft Developer Network's Checkbox Class. It may not be obvious, but these top level accessibility APIs have a direct relationship with web technology development, and are critical for the accessibility of interactive ARIA Widgets in particular.įor example, at the platform level in the Windows OS, there is a Checkbox control type.
HTML5 ACCESSIBILITY SCREEN READER MAC
This is MSAA/UIA/IAccessible2 on Windows, AT-SPI/IAccessible2 on Linux, the OS X Accessibility Protocol on Mac and iOS, and so on. Detailed dates and version information can be found in associated tests.At the top level, the first concept to understand is the platform Accessibility API, which is an integral part of each Operating System. Results across all tests for this feature range from a year ago to 3 years ago. If this is the case for your implementation, it might be fine to use a dl element and hope for better support in the future.
It is often possible for a user to determine which text is a key and which text is a value just based upon the text alone. If it is critically important to convey relationships between terms and descriptions and the values of the two can be confused with each other (think a matching list of colors such as "red: blue", consider another approach such as a table or headings. The dl element and its associated dt and dd elements have poor to non-existent support. See the related dt element and the dd element for more information. Voice Control support level: unknown On this pageĭescription list element.