जादू का उपयोग कर रहा #ahah / #ajax कि जिस तरह से आप को परिभाषित कर सकते क्या संशोधन उत्प्रेरित करने चाहिए और क्या एक परिणाम के रूप संशोधित किया जाना चाहिए प्रपत्र तत्वों के साथ संपत्ति, के अलावा यह jQuery के साथ जुड़ जाता है।
नीचे दिए गए उदाहरण से यह महत्वपूर्ण हिस्सा है:
'#ajax' => array(
'event' => 'change',
'callback' => 'myajax_ajax_callback',
'wrapper' => 'dropdown_second_replace',
),
यहां एक उदाहरण है जो दो ड्रॉपडाउन के साथ एक फॉर्म-आधारित पेज दिखाता है: दूसरी ड्रॉपडाउन में विकल्पों की सूची पहली ड्रॉपडाउन में चयन पर निर्भर करती है।
<?php
/**
* Implementation of hook_menu().
* Registers a form-based page that you can access at "http://localhost/myajax"
*/
function myajax_menu(){
return array(
'myajax' => array(
'title' => 'A page to test ajax',
'page callback' => 'drupal_get_form',
'page arguments' => array('myajax_page'),
'access arguments' => array('access content'),
)
);
}
/**
* A form with a dropdown whose options are dependent on a
* choice made in a previous dropdown.
*
* On changing the first dropdown, the options in the second are updated.
*/
function myajax_page($form, &$form_state) {
// Get the list of options to populate the first dropdown.
$options_first = myajax_first_dropdown_options();
// If we have a value for the first dropdown from $form_state['values'] we use
// this both as the default value for the first dropdown and also as a
// parameter to pass to the function that retrieves the options for the
// second dropdown.
$value_dropdown_first = isset($form_state['values']['dropdown_first']) ? $form_state['values']['dropdown_first'] : key($options_first);
$form['dropdown_first'] = array(
'#type' => 'select',
'#title' => 'First Dropdown',
'#options' => $options_first,
'#default_value' => $value_dropdown_first,
// Bind an ajax callback to the change event (which is the default for the
// select form type) of the first dropdown. It will replace the second
// dropdown when rebuilt
'#ajax' => array(
// When 'event' occurs, Drupal will perform an ajax request in the
// background. Usually the default value is sufficient (eg. change for
// select elements), but valid values include any jQuery event,
// most notably 'mousedown', 'blur', and 'submit'.
'event' => 'change',
'callback' => 'myajax_ajax_callback',
'wrapper' => 'dropdown_second_replace',
),
);
$form['dropdown_second'] = array(
'#type' => 'select',
'#title' => 'Second Dropdown',
// The entire enclosing div created here gets replaced when dropdown_first
// is changed.
'#prefix' => '<div id="dropdown_second_replace">',
'#suffix' => '</div>',
// when the form is rebuilt during ajax processing, the $value_dropdown_first variable
// will now have the new value and so the options will change
'#options' => myajax_second_dropdown_options($value_dropdown_first),
'#default_value' => isset($form_state['values']['dropdown_second']) ? $form_state['values']['dropdown_second'] : '',
);
return $form;
}
/**
* Selects just the second dropdown to be returned for re-rendering
*
* Since the controlling logic for populating the form is in the form builder
* function, all we do here is select the element and return it to be updated.
*
* @return renderable array (the second dropdown)
*/
function myajax_ajax_callback($form, $form_state) {
return $form['dropdown_second'];
}
/**
* Helper function to populate the first dropdown. This would normally be
* pulling data from the database.
*
* @return array of options
*/
function myajax_first_dropdown_options() {
return array(
'colors' => 'Names of colors',
'cities' => 'Names of cities',
'animals' => 'Names of animals',
);
}
/**
* Helper function to populate the second dropdown. This would normally be
* pulling data from the database.
*
* @param key. This will determine which set of options is returned.
*
* @return array of options
*/
function myajax_second_dropdown_options($key = '') {
$options = array(
'colors' => array(
'red' => 'Red',
'green' => 'Green',
'blue' => 'Blue'
),
'cities' => array(
'paris' => 'Paris, France',
'tokyo' => 'Tokyo, Japan',
'newyork' => 'New York, US'
),
'animals' => array(
'dog' => 'Dog',
'cat' => 'Cat',
'bird' => 'Bird'
),
);
if (isset($options[$key])) {
return $options[$key];
}
else {
return array();
}
}