Google DTorial: An interactive tutorial framework for blind users in a Web 2.0 world - Manual (Page 9)

one specific aspect of a program via tutorial. The random content access system can
be further enhanced through tutorial searching. Designers must remember that
“finding” is universal. Blind or sighted, users want to find an answer to a specific
question. Allowing random access to content ensure a quick resolution.
6.3 Users Felt that They Did Not Know What was Occurring and were Not in
Control of Navigation
In an AJAX application where pages change dynamically without page reloads, the
screen-reader user relies upon the application to notify him when content changes.
Though this is critical for Web 2.0 application design, it also influences the design of
tutorials. For example, early in the DTorial design cycles, all tutorial content was
injected directly to the screen reader. However, when text was injected in this manner,
users were unable to reread in their traditional manner; reading by paragraph,
sentence, or even words. One user stated that:
I didn't have to read a whole section at a time, I could go back
through an read word by word, line by line... - PP1
Lack of notifications when content changed, and the inability to read at one’s own
pace, caused considerable distress and made users feel like the “were not in control.”
RECOMMENDATION:
Always Keep Users Informed and in Control With Feedback
Tutorials and Web 2.0 applications can address this problem though a solution like
AxsJAX and inject content to be read when dynamic changes are made to the DOM.
Further, when the screen-reader user wants to jump to a chapter, he must be able to
select the new topic, and be notified that he is at a new location on the page. In
addition, content in the tutorial must be book-ended, with both a header up front and a
textual warning at the end that he is leaving the tutorial and returning to the Web
application. This allows him to easily find the content again, and alerts him when he
is leaving the tutorial information and reentering the application.
In the above example relating to DTorial content, we modified the system to inject
tutorial text directly into the DOM, so that browsers treated it as actual page text,
permitting users to read the tutorial content in the same manner as they read other
web pages (whole text, line-by-line, and/or word-by-word). The text was inserted
directly above the topic of discussion (e.g., the chapter on folders would be injected
just before the folder list). As users moved from chapter to chapter, the old tutorial
text would be removed and new text would be added. Yet as long as the user was in
one section/chapter/topic of the tutorial, the content remained for reference at any
point, so users could try out what they learned along the way. We further
demonstrated that the text could be hidden with CSS and still be accessed by screen
readers, thus making the tutorial only visible to a screen reader user.