Missing `dt-type` classes on `th` and `td` elements for server-side implementations

nanone

Link to test case: https://datatables.net/examples/server_side/post.html
Description of problem:

After skimming through a bunch of the examples I've narrowed down the problem to what seems to be "server-side":

1. All "server-side" examples initially render datatables <th> and <td> elements without dt-type classes. The initial alignment is therefore incorrect.
2. If the user sorts one of the columns, the <th> element will get a dt-type class, but the corresponding <td> elements will not, therefore leading to a visually worse misalginment between header and colums cells.

Let's take 2 examples, one "server-side" and one other one type, where we will both look at the Salary column.

• "POST"

  • Here on first load we can see that the <th> element for the Salary field has classes dt-orderable-asc dt-orderable-desc. The <td> elements under this column have no classes.
  • If we start to sort the column once, we see that <th> element has the classes dt-orderable-asc dt-orderable-desc dt-type-numeric dt-ordering-asc, but the underlying <td> element only has a sorting class sorting_1.
  • The result: misalignment between <th> and <td> elements for this column.

• "AJAX data source arrays"

  • Here on first load we can see that the <th> element for the Salary field has classes dt-orderable-asc dt-orderable-desc dt-type-numeric. The <td> elements under this column havedt-type-numeric` classes.
  • If we start to sort the column once, we see that <th> element has the classes dt-orderable-asc dt-orderable-desc dt-type-numeric dt-ordering-asc, and the underlying <td> element have dt-type-numeric sorting_1 classes.
  • The result: correct alignment between <th> and <td> elements for this column.

I hope this is enough information to further debug the problem.

allan

Hi,

With my work on DataTables 2.1 I've been looking into exactly this issue. The key problem is that client-side data detection simply does not work when server-side processing is enabled. It can't ever work as it doesn't have the full set of data available for the column.

As a result I've intentionally disabled type detection for server-side processing. If you want classes such as dt-type-numeric for a column, then you can absolutely add them using columns.className, but that works because you have knowledge of the full dataset, which DataTables does not.

Allan