Code snippet: How to set the disabled or readonly attribute of a CCK field

Here's a code snippet that you can use to set the disabled attribute of a CCK field.

First, you need to create a small module containing the following code:

ssf

/**
* @file
* Custom module to set the disabled attribute of CCK fields.
*/

/**
* Implementation of hook_form_alter().
*/
function mysnippet_form_alter(&$form, $form_state, $form_id) {
if (isset($form['type']) && isset($form['#node'])) {
// Use this check to match node edit form for a particular content type.
if ('mytype_node_form' == $form_id) {
$form['#after_build'][] = '_mysnippet_after_build';
}
// Use this check to match node edit form for any content type.
// if ($form['type']['#value'] .'_node_form' == $form_id) {
// $form['#after_build'][] = '_mysnippet_after_build';
// }
}
}

/**
* Custom after_build callback handler.
*/
function _mysnippet_after_build($form, &$form_state) {
// Use this one if the field is placed on top of the form.
_mysnippet_fix_disabled($form['field_myfield']);
// Use this one if the field is placed inside a fieldgroup.
// _mysnippet_fix_disabled($form['group_mygroup']['field_myfield']);
return $form;
}

/**
* Recursively set the disabled attribute of a CCK field
* and all its dependent FAPI elements.
*/
function _mysnippet_fix_disabled(&$elements) {
foreach (element_children($elements) as $key) {
if (isset($elements[$key]) && $elements[$key]) {

// Recurse through all children elements.
_mysnippet_fix_disabled($elements[$key]);
}
}

if (!isset($elements['#attributes'])) {
$elements['#attributes'] = array();
}
$elements['#attributes']['disabled'] = 'disabled';
}

SOURCE:http://drupal.org/node/357328