Re: An improvement for a reading of exported HTML tables

[Sebastian Rose <sebastian_rose@gmx.de>]

Jan Buchal <buchal@brailcom.org> writes:
>     CD> On May 7, 2009, at 12:44 PM, Jan Buchal wrote:
>
>>>>>>> "CD" == Carsten Dominik <carsten.dominik@gmail.com> writes:
>     >> 
>     CD> On May 7, 2009, at 11:38 AM, Jan Buchal wrote:
>>
>>> Hello again,
>>>>
>>>> the problem is little bit complicate :-) I need <th> not in first
>>>> row only but by every column which contain the name of row. In
>>>> the attachment you can find the example
>>
>>    CD> That is currently not possible.
>> And is it possible fix it? From the point of view of accessibility is a
>> bug.
>
>     CD> I would not call it a bug, it is a limitation. Org is not a full
>     CD> HTML table editor, there are many things it cannot do, including
>     CD> column and row spanning, multiline fields, you name it.
> Unfortunately it is a bug. See please WCAG documentation. 


It's not. It's just something not implemented. And, as I see it, it
would be complicated to implement.


What you want seems to be this:

  1. It's recommended to put the column headers into the <thead> element
     (Org-mode does this). That way column headers are re-printed on every
     page, if a table exceeds the size of one printed page.

  2. It's recommended to use <th> elements in tables like this:

  | Country | Number of citizens  |
  |---------+--------------------|
  | Germany | 84 Mio.            |
  | France  | XXX Mio.           |

  In this case it could make sense to put the country names in <th>
  tags (see 4.). I think this is, what you wanted.


  3. Use the caption element to describe the purpose of a
     table. Org-mode does this.
  

  4. The `scope' attribut describes, wich table cells are concerned by
     the <th> element.

     Again, our country example. This table should be handled corretly
     by a screen reader:

     <table>
      <caption>Citizens per country</caption>
      <thead>
       <tr>
        <th scope="col"> Country </th>
        <th scope="col"> Number of citizens </th>
       </tr>
     </thead>
     <tbody>
      <tr>
       <th scope="row"> Germany </th>
       <td> 84 Mio. </td>
      </tr>
      <tr>
       <th scope="row"> France </th>
       <td> XXX Mio. </td>
      </tr>
      ...


There are more possible values for `scope' (`colgroup' and `rowgroup')
as well, as some additional possibilities to assign headers to cells
(`header' and `id') in such a way, that multiple headers describe one
cell.

In our example, the headers `Germany' and `Number of citizens' would
describe the cell `84 Mio.'.



I don't see, how Org-mode could decide which headers describe wich
cells.

The most obvious thing to do would be, to


    a) mark cells as table-headers (this is the only needed new
       Org-syntax feature),
    b) if in the first table row, add a  scope="col" to the <th> tag,
    c) if in the first column, add a   scope="row"  to  the <th> tag. 



Beacuse if we take all those possible assignments into account, we'll
get something complicated to code, use and document...
We would have to end with some kind of `formular' syntax, like the one
used for the spreadsheet capabilities.


Regards

   Sebastian