Render Taxonomy Vocabulary in Custom Form

Try changing #type to checkbox_tree and let me know if that works.

ooO! I think this issue addresses close to what I need on a similar challenge. I'm making a custom form that generates lesson nodes (as part of a migration process - can't use standard form) and using your suggestion and some info on the first post I created this:

<?php
function lesson_mover($form, &$form_state) {
//...

	$form['lesson_standards'] = array(
		'#title' => 'Subject Areas/Standards',
		'#type' => 'checkbox_tree',
		'#vocabulary' => 5,
		'#parent_tid' => 0,
		'#value_key' => 'tid',
	);

//...
?>

That gets me a nice expanded radiobutton list with the hierarchy of my vocabulary. Cool! (let me know if that helps answer this issue that's been dead for a while)

Bonus challenges:
Any thoughts on how I can make my form element a list of checkboxes for multiple values to be selected, make only the last leaf selectable, and make it show in one of those excellent expanding trees?

Thanks for the added assist in advance. :D

Chris

Regarding the "bonus challenges", this works!:

<?php
//...
$term_reference_tree_path = drupal_get_path('module', 'term_reference_tree');
$form['lesson_standards'] = array(
	'#title' => 'Subject Areas/Standards',
	'#type' => 'checkbox_tree',
	'#max_choices' => 999,
	'#leaves_only' => 1,
	'#start_minimized' => TRUE,
	'#depth' => 0,
	'#vocabulary' => 5,
	'#parent_tid' => 0,
	'#value_key' => 'tid',
	'#select_parents' => TRUE,
	'#attached' => array(
		'js' => array($term_reference_tree_path . '/term_reference_tree.js'),
		'css' => array($term_reference_tree_path . '/term_reference_tree.css')
	),
	'#attributes' => array('class' => array('field-widget-term-reference-tree')),
);
//...
?>

Sorry, I accidentally changed the title earlier...

Hmmmm. This doesn't validate though when I submit the form, highlighting my tree in red once I select an option (validates fine if empty):

Warning: Illegal offset type in isset or empty in _form_validate() (line 1298 of /my/server/root/html/includes/form.inc).
An illegal choice has been detected. Please contact the site administrator.

Even if I add a custom validate function:

<?php
//...
	'#element_validate' => array('_lesson_mover_standards_validate'),
//...

function _lesson_mover_standards_validate(&$element, &$form_state) {
	//do nothing for now...
}

?>

Any thoughts on what could be wrong? I'll keep digging...

EDIT:

In form.inc at line 1297-1298:

<?php
//...
          foreach ($value as $v) {
            if (!isset($options[$v])) {
//...
?>

I can see why the error is happening. Here's what $v looks like:

Array
(
    [186] => Array
        (
            [186-children] => Array
                (
                    [187] => Array
                        (
                            [187-children] => Array
                                (
                                    [188] => Array
                                        (
                                            [188] => 188
                                        )

                                )

                        )

                )

        )

)

Any thoughts on how to get around this oddness? :S

Thanks again,

Hrmmm. I'm still stuck on this one. Any ideas? Thanks again,

Here is fixed version of bonus challenge, this should fix the error from comment #6.

//...
$term_reference_tree_path = drupal_get_path('module', 'term_reference_tree');
$form['lesson_standards'] = array(
    '#title' => 'Subject Areas/Standards',
    '#type' => 'checkbox_tree',
    '#max_choices' => 999,
    '#leaves_only' => 1,
    '#start_minimized' => TRUE,
    '#depth' => 0,
    '#vocabulary' => 5,
    '#parent_tid' => 0,
    '#value_key' => 'tid',
    '#select_parents' => TRUE,
    '#attached' => array(
        'js' => array($term_reference_tree_path . '/term_reference_tree.js'),
        'css' => array($term_reference_tree_path . '/term_reference_tree.css')
    ),
    '#attributes' => array('class' => array('field-widget-term-reference-tree')),
    '#element_validate' => array('_term_reference_tree_widget_validate'),
    '#value' => array(),
);
//...

Added rows explained:

'#element_validate' => array('_term_reference_tree_widget_validate')

This custom element_validate function is basically a workaround for the validation error. From the function comments: "This function sets the value of the tree widgets into a form that Drupal can understand, and also checks if the field is required and has been left empty.".

'#value' => array(),

In addition to #element_validate #value is also needed and for the same reason I'd imagine. _term_reference_tree_widget_validate overwrites #value so it doesn't matter too much what the initial value is.

All the required element properties can be found from function term_reference_tree_field_widget_form(). Obviously these things could be improved to make it easier to use the widget as form API element.

Aha! I knew I was missing something. I tried the '#element_validate' but didn't have the '#value' in place at the same time.

Thanks so much for your help! This resolved the error issue I was running into when submitting custom form.

:D :D :D :D :D