Without writing your code, you cannot.
To make a table (which isn't a form element) draggable, you first call theme('table')
and then drupal_add_tabledrag()
. With a tableselect form element, you don't call theme('table')
, so you cannot call drupal_add_tabledrag()
either.
What you could do is implementing a new form element and, in the theme function associated to that form element, call theme('table')
and then drupal_add_tabledrag()
. theme_tableselect()
code can be used as guideline.
function theme_tableselect($variables) {
$element = $variables['element'];
$rows = array();
$header = $element['#header'];
if (!empty($element['#options'])) {
// Generate a table row for each selectable item in #options.
foreach (element_children($element) as $key) {
$row = array();
$row['data'] = array();
if (isset($element['#options'][$key]['#attributes'])) {
$row += $element['#options'][$key]['#attributes'];
}
// Render the checkbox / radio element.
$row['data'][] = drupal_render($element[$key]);
// As theme_table only maps header and row columns by order, create the
// correct order by iterating over the header fields.
foreach ($element['#header'] as $fieldname => $title) {
$row['data'][] = $element['#options'][$key][$fieldname];
}
$rows[] = $row;
}
// Add an empty header or a "Select all" checkbox to provide room for the
// checkboxes/radios in the first table column.
if ($element['#js_select']) {
// Add a "Select all" checkbox.
drupal_add_js('misc/tableselect.js');
array_unshift($header, array(
'class' => array(
'select-all',
),
));
}
else {
// Add an empty header when radio buttons are displayed or a "Select all"
// checkbox is not desired.
array_unshift($header, '');
}
}
return theme('table', array(
'header' => $header,
'rows' => $rows,
'empty' => $element['#empty'],
'attributes' => $element['#attributes'],
));
}
Keep in mind the conditions reported in drupal_add_tabledrag()
for the dragging to work, including that the table must have an ID attribute which must be equal to the first argument passed to drupal_add_tabledrag()
, and each table row needs a weight value (which is used to sort the rows).