Table: Need to generate comlex th

[kiwibrit]

I have a series of dynamically driven tables, generated according to various parameters. I don't think they are as accessible as they should be, and would like some advice.

There are 3 different entry pages to create a table - this is as good as any. You make a selection on this page, followed by another on the next, and then a table is generated.

I can introduce a table caption and summary easily. But I can't figure how to arrange the <th> tags.

At the moment my latest attempt at the coding looks something like this:

<table width="512" summary="This table shows the
 sizes of blinds possible with a XXXXX tube and a XXXX drive.">
  <caption>
  BLIND SIZES POSSIBLE WITH A XXXXX TUBE AND XXXX DRIVE
  </caption>
        <colgroup align="right"></colgroup>
    <colgroup align="center"></colgroup>
    <colgroup align="center"></colgroup>
    <colgroup align="center"></colgroup>
    <colgroup align="center"></colgroup>
    <thead valign="top">
    <tr>
      <th style="text-align:left; font-weight:normal;      font-size:.7em;">Drop</th>
      <th style="text-align:center; font-weight:normal; font-size:.7em;">500</th>
      <th style="text-align:center; font-weight:normal; font-size:.7em;">800</th>
      <th style="text-align:center; font-weight:normal; font-size:.7em;">1000</th>
      <th style="text-align:center; font-weight:normal; font-size:.7em;">1200</th>
    </tr>
     </thead>
      <tr>
        <td>200</td>
        <td>X</td>
        <td>X</td>
        <td>X</td>
        <td>X</td>
        </tr>
        <tr>
        <td>400</td>
        <td>X</td>
         <td>X</td>
         <td>X</td>
         <td>X</td>
       </tr>
       <tr>
          <td>600</td>
          <td>X</td>
          <td>X</td>
          <td>X</td>
          <td>X</td>
        </tr>
        <tr>
           <td>800</td>
           <td>X</td>
           <td>X</td>
           <td>X</td>
           <td>X</td>
        </tr>
        <tr>
           <td>1000</td>
           <td>X</td>
           <td>X</td>
           <td>X</td>
           <td>X</td>
          </tr>
</table>

But what I think is needed is a 4-column wide heading called "width" above
the specific width-value ("600", "800" etc) headings. In other words, like my present size tables - but meeting accessibility criteria.

Is that possible?

[Charles]

Is that possible?

Certainly. Just make good use of the TBODY and THEAD elements and the "abbr", "axis" and "headers" attributes. See http://www.w3.org/TR/html401/struct/tables.html .

[kiwibrit]

Thank you. I think that will do the trick. I'll play with that tomorrow.

[kiwibrit]

OK, changing the code relating to <thead> and <th> to:

                <thead valign="top">
                <tr>
                    <th>Drop</th>
                    <th colspan="4">Width</th>
                </tr>
                <tr><th>&nbsp;</th>
                    <th>500</th>
                    <th>800</th>
                    <th>1000</th>
                    <th>1200</th>
                </tr>
                </thead>

gets what I want visually, passes the w3c validator, and passes watchfire

Are there any practical problems for accessibility with using &nbsp; as I have - and in having the 4-column span "Width" <th> sitting on top of the "400", "600","800", and "1000" <th>s?

Here's a test page sample, it would need a tidy up of the styling - but it shows the idea.