Notes on Techniques for accessing content.

Reference document:
  [1] http://www.w3.org/WAI/UA/WAI-USERAGENT-TECHS-19990716/

Hello,

Section 3.1 of [1] talks of techniques for accessing content.
Here are some initial notes that might serve as the
basis for fleshing out this section. All comments welcome.
In particular, developers are encouraged to suggest details
about how certain tasks may be accomplished on a particular
platform.

Thank you,

 - Ian

Rationale: 
    It is not sufficient to convert a rendering intended for
    one medium into a rendering for a different medium (e.g.,
    a graphical rendering to speech) since structural information
    is lost. Examples: table cells, nested lists (want to know where
    list item ends).

    Also, serial access to content not always convenient, so
    need additional mechanisms to select and receive content.

Where does content come from?

  Some combination of document source, style sheets (which may
  hide content or generate content), and user agent additions (which
  may add contextual information or dynamic information such
  as whether a link has been visited).

  In addition, the user agent may want to provide "intelligent"
  access to content to simplify the view or to convey models
  more familiar to users than what is conveyed by the DTD alone.
   
What does access mean?

  Access means that the user agent renders selected content.
  Content includes alternative equivalents (e.g., attribute
  values).  [Cross-link to sections about alternative content in HTML
  specifically.]

  In the simplest case, the user agent renders the document
  (e.g., two-dimensional graphical layout, audio stream, 
  line-by-line braille stream) and the user has access to
  the entire rendering.

  But this is not sufficient and so the user agent must
  provide navigation mechanisms that allow the user to
  set the selection/focus and then request the selected content
  (or information about the content - refer to another section...).

  User interface issues: 
     How to indicate what piece of content one wants to access?
     How does the user agent present the information?
     How does the user configure the user agent to present 
         associated contextual information?

  Refer to the section on navigation for different navigation
  techniques (serial, direct, tree, etc.). [The section on 
  navigation should be part of another email. Some advance
  ideas: configuration of navigation, navigating sets of
  items (but not always linear, e.g., tables).]

Structured v. Unstructured selection.

  Users may want to select content based on the rendering
  structure alone (i.e., that amounts to selecting across
  element borders).

  Users may want to select content based on structure (e.g.,
  a table cell).

Contextual information

  In addition to providing information about content, user agents
  should provide contextual information. Examples: table cell
coordinates
  or header information. Or list item number within nested lists.

  Contextual information includes language of content as well.

  [There will probably be more to say on context, but in another
section.]

Received on Thursday, 29 July 1999 20:28:08 UTC