Drupal combo box

How开发者_如何学Go do you create a combo box using Drupal Form API (FAPI)?

Since there is no combobox form element you will need to use hook_elements() and a callback to create a custom combobox form element

Check out these docs for an example of how to use hook_elements()

If by combobox you mean a drilldown, check out hierarchical select

Here is another technique for multigroup: http://drupal.org/project/flexifield

But maybe by combo box you wanted this: http://drupal.org/project/select_or_other

If neither of those do it, here is a post about more complex hierarchal options... http://groups.drupal.org/node/23899