Isn ARIA expensive to implement in browsers? Does it double the amount of widget code?
No, ARIA is not expensive to implement. In fact it is significantly easier to implement in a browser than implementing HTML 5 widgets. First, it lines up nicely with how accessibility APIs work. It’s mostly a matter of adding a table of role and properties to API support. Second, unlike natural widgets, it does not require code to be added to the core browser — only to the module that implements accessibility proxy objects. The accessibility module simply passes the roles, states and state changes on through the APIs they already support, and this can be done on the base accessibility object class. The entire Firefox implementation of ARIA was essentially coded by one person, in addition to much other accessibility work. Documentation on mapping ARIA to desktop accessibility APIs has provided to assist other developers of other browsers. Most of the code for the Firefox ARIA implementation is as follows: • A table mapping ARIA roles and states to API roles and states • A set of IAcces
