How to add a text Autocomplete Widget programmatically

Question

Trying to include a text Autocomplete Widget in a compound field (more here) using the snipped below.. but the field does not autocomplete. What am I doing wrong?

  $element['contact_name'] = array(
    '#title' => t('Name'),
    '#type' => 'textfield',
    '#default_value' => $defaults['contact_name'],
    '#weight' => 2,
    '#size' => '100',
    '#max_length' => '255',
    '#widget_type' => 'autocomplete_widgets_flddata',
    '#autocomplete_match' => 'contains',
    '#autocomplete_case' => '0',
    '#widget_module' => 'autocomplete_widgets',
  );

Answer 1

Ok, so if you're trying to do it through hook_form_alter, you have to read the documentation on altering CCK fields.

The short version: the CCK fields are processed after the form is built. If you want to change anything in them, you have to add a callback to $form['#after_build'] (but do not replace the array, just add to it). Then implement the function, change values in $form and return the $form.