ajax_example_node_form_alter.inc

<?php


/**
 * @file
 * This example shows how to use AJAX when altering a node form.
 *
 * It maintains a table parallel to the node table containing attributes
 * 'example_1' and 'example_2' which are displayed on the node form.
 * 'example_2' is displayed dynamically when example_1 is checked.
 */

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Adds two fields to the node form, second only appears after first is enabled.
 */
function ajax_example_form_node_form_alter(&$form, &$form_state, $form_id) {
    $node = $form['#node'];
    $form['ajax_example_1'] = array(
        '#type' => 'checkbox',
        '#title' => t('AJAX Example 1'),
        '#description' => t('Enable to show second field.'),
        '#default_value' => $node->ajax_example['example_1'],
        '#ajax' => array(
            'callback' => 'ajax_example_form_node_callback',
            'wrapper' => 'ajax-example-form-node',
            'effect' => 'fade',
        ),
    );
    $form['container'] = array(
        '#prefix' => '<div id="ajax-example-form-node">',
        '#suffix' => '</div>',
    );
    // If the state values exist and 'ajax_example_1' state value is 1 or
    // if the state values don't exist and 'example1' variable is 1 then
    // display the ajax_example_2 field.
    if (!empty($form_state['values']['ajax_example_1']) && $form_state['values']['ajax_example_1'] == 1 || empty($form_state['values']) && $node->ajax_example['example_1']) {
        $form['container']['ajax_example_2'] = array(
            '#type' => 'textfield',
            '#title' => t('AJAX Example 2'),
            '#description' => t('AJAX Example 2'),
            '#default_value' => empty($form_state['values']['ajax_example_2']) ? $node->ajax_example['example_2'] : $form_state['values']['ajax_example_2'],
        );
    }
}

/**
 * Returns changed part of the form.
 *
 * @return array
 *   Form API array.
 *
 * @see ajax_example_form_node_form_alter()
 */
function ajax_example_form_node_callback($form, $form_state) {
    return $form['container'];
}

/**
 * Implements hook_node_submit().
 * @see ajax_example_form_node_form_alter()
 */
function ajax_example_node_submit($node, $form, &$form_state) {
    $values = $form_state['values'];
    // Move the new data into the node object.
    $node->ajax_example['example_1'] = $values['ajax_example_1'];
    // Depending on the state of ajax_example_1; it may not exist.
    $node->ajax_example['example_2'] = isset($values['ajax_example_2']) ? $values['ajax_example_2'] : '';
}

/**
 * Implements hook_node_prepare().
 *
 * @see ajax_example_form_node_form_alter()
 */
function ajax_example_node_prepare($node) {
    if (empty($node->ajax_example)) {
        // Set default values, since this only runs when adding a new node.
        $node->ajax_example['example_1'] = 0;
        $node->ajax_example['example_2'] = '';
    }
}

/**
 * Implements hook_node_load().
 *
 * @see ajax_example_form_node_form_alter()
 */
function ajax_example_node_load($nodes, $types) {
    $result = db_query('SELECT * FROM {ajax_example_node_form_alter} WHERE nid IN(:nids)', array(
        ':nids' => array_keys($nodes),
    ))->fetchAllAssoc('nid');
    foreach ($nodes as &$node) {
        $node->ajax_example['example_1'] = isset($result[$node->nid]->example_1) ? $result[$node->nid]->example_1 : 0;
        $node->ajax_example['example_2'] = isset($result[$node->nid]->example_2) ? $result[$node->nid]->example_2 : '';
    }
}

/**
 * Implements hook_node_insert().
 *
 * @see ajax_example_form_node_form_alter()
 */
function ajax_example_node_insert($node) {
    if (isset($node->ajax_example)) {
        db_insert('ajax_example_node_form_alter')->fields(array(
            'nid' => $node->nid,
            'example_1' => $node->ajax_example['example_1'],
            'example_2' => $node->ajax_example['example_2'],
        ))
            ->execute();
    }
}

/**
 * Implements hook_node_update().
 * @see ajax_example_form_node_form_alter()
 */
function ajax_example_node_update($node) {
    if (db_select('ajax_example_node_form_alter', 'a')->fields('a')
        ->condition('nid', $node->nid, '=')
        ->execute()
        ->fetchAssoc()) {
        db_update('ajax_example_node_form_alter')->fields(array(
            'example_1' => $node->ajax_example['example_1'],
            'example_2' => $node->ajax_example['example_2'],
        ))
            ->condition('nid', $node->nid)
            ->execute();
    }
    else {
        // Cleaner than doing it again.
        ajax_example_node_insert($node);
    }
}

/**
 * Implements hook_node_delete().
 * @see ajax_example_form_node_form_alter()
 */
function ajax_example_node_delete($node) {
    db_delete('ajax_example_node_form_alter')->condition('nid', $node->nid)
        ->execute();
}