FRAME should have valid LONGDESC |
WAI / WCAG 1.0 Priority 2 checkpoint 12.2
Issue Description The page contains FRAMESET and FRAME elements with a LONGDESC attribute that is not valid.
How to fix It appears that a long description for a frame is needed,as there is a LONGDESC attribute that is already defined. However, the value of the LONGDESC attribute is not valid. A valid LONGDESC satisfies all the following conditions:

1. it is not empty (i.e. different than "")
2. it is not blank (i.e. with one or more spaces, " ")
3. the file it refers to is not empty or blank
4. the file it refers to exists and contains HTML code
5. the file it refers to can be accessed via HTTP or FTP.

See the Explanation section for a detailed example.

Issue Explanation Frames are mainly used for grouping information and navigation items, and displaying them with a certain page layout. However some assistive technologies (reading browsers, screen readers, textual browsers) are not able to employ the visual layout. These tools therefore render each single frame out of context, without any reference to the other frames. The user of these tools cannot perceive the other frames and their content. That is why it is important that each frame carries within it a description that allows the user to build the context.

Names like "top", "bottom-left" that are usually adopted for frame names are not sufficiently descriptive and do not help the user in building the missing context.

Consider the following example (taken from HTML Techniques for Web Content Accessibility Guidelines 1.0 [http://www.w3.org/TR/WCAG10-HTML-TECHS/#frame-text-equivalent] and slightly modified):

    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN">
    <HTML>
      <HEAD>
        <TITLE>Today's news</TITLE>
      </HEAD>

      <FRAMESET cols="10%,*,10%">

      <FRAMESET rows="20%,*">
        <FRAME src="promo.html" name="promo" title="promotions">
        <FRAME src="sitenavbar.html" name="navbar"
           title="Sitewide navigation bar" longdesc="frameset-desc.html#navbar">
      </FRAMESET>

      <FRAME src="story.html" name="story" title="Selected story - main content"
         longdesc="frameset-desc.html#story">

      <FRAMESET rows="*,20%">
        <FRAME src="headlines.html" name="index" title="Index of other
          national headlines" longdesc="frameset-desc.html#headlines">
        <FRAME src="ad.html" name="adspace" title="Advertising">
      </FRAMESET>

      <NOFRAMES>
        <p><a href="noframes.html">No frames version</a></p>
        <p><a href="frameset-desc.html">Descriptions of frames.</a></p>

      </NOFRAMES>

      </FRAMESET>
    </HTML>

frameset-desc.html might say something like:

    #Navbar - this frame provides links to the <a href="sitenavbar.html">major
              sections of the site</a>:  World News, National News,
              Local News, Technological News,
              and Entertainment News.

    #Story  - this frame displays the <a href="story.html">currently selected story</a>.

    #Index  - this frame provides links to the day's
              <a href="headlines.html">headline stories</a> within this section.

Notice the NOFRAMES element is useful when special purpose browsers are used that do not support frames (for example on PDAs and cell phones).