class Autotextfields
Same name in other branches
- 3.x modules/ajax_example/src/Form/Autotextfields.php \Drupal\ajax_example\Form\Autotextfields
- 4.0.x modules/ajax_example/src/Form/Autotextfields.php \Drupal\ajax_example\Form\AutoTextFields
Show textfields based on AJAX-enabled checkbox clicks.
Hierarchy
- class \Drupal\ajax_example\Form\Autotextfields extends \Drupal\Core\Form\FormBase
Expanded class hierarchy of Autotextfields
Related topics
1 string reference to 'Autotextfields'
- ajax_example.routing.yml in ajax_example/
ajax_example.routing.yml - ajax_example/ajax_example.routing.yml
File
-
ajax_example/
src/ Form/ Autotextfields.php, line 13
Namespace
Drupal\ajax_example\FormView source
class Autotextfields extends FormBase {
/**
* {@inheritdoc}
*/
public function getFormId() {
return 'ajax_example_autotextfields';
}
/**
* {@inheritdoc}
*
* This form has two checkboxes which the user can check in order to then
* reveal the first and/or last name text fields.
*
* We could perform this behavior with #states. We might not want to if, for
* instance, we wanted to require a name, but let the user choose whether
* to enter first or last or both.
*
* For all the requests this class gets, the buildForm() method will always be
* called. If an AJAX request comes in, the form state will be set to the
* state the user changed that caused the AJAX request. So if the user enabled
* one of our checkboxes, it will be checked in $form_state.
*/
public function buildForm(array $form, FormStateInterface $form_state) {
$form['description'] = [
'#type' => 'item',
'#markup' => $this->t('This form demonstrates changing the status of form elements through AJAX requests.'),
];
$form['ask_first_name'] = [
'#type' => 'checkbox',
'#title' => $this->t('Ask me my first name'),
'#ajax' => [
'callback' => '::textfieldsCallback',
'wrapper' => 'textfields-container',
'effect' => 'fade',
],
];
$form['ask_last_name'] = [
'#type' => 'checkbox',
'#title' => $this->t('Ask me my last name'),
'#ajax' => [
'callback' => '::textfieldsCallback',
'wrapper' => 'textfields-container',
'effect' => 'fade',
],
];
// Wrap textfields in a container. This container will be replaced through
// AJAX.
$form['textfields_container'] = [
'#type' => 'container',
'#attributes' => [
'id' => 'textfields-container',
],
];
$form['textfields_container']['textfields'] = [
'#type' => 'fieldset',
'#title' => $this->t("Generated text fields for first and last name"),
'#description' => $this->t('This is where we put automatically generated textfields'),
];
// This form is rebuilt on all requests, so whether or not the request comes
// from AJAX, we should rebuild everything based on the form state.
// Checkbox values are expressed as 1 or 0, so we have to be sure to compare
// type as well as value.
if ($form_state->getValue('ask_first_name', NULL) === 1) {
$form['textfields_container']['textfields']['first_name'] = [
'#type' => 'textfield',
'#title' => $this->t('First Name'),
'#required' => TRUE,
];
}
if ($form_state->getValue('ask_last_name', NULL) === 1) {
$form['textfields_container']['textfields']['last_name'] = [
'#type' => 'textfield',
'#title' => $this->t('Last Name'),
'#required' => TRUE,
];
}
$form['textfields_container']['submit'] = [
'#type' => 'submit',
'#value' => $this->t('Click Me'),
];
return $form;
}
/**
* {@inheritdoc}
*/
public function submitForm(array &$form, FormStateInterface $form_state) {
$this->messenger()
->addMessage($this->t('Submit handler: First name: @first_name Last name: @last_name', [
'@first_name' => $form_state->getValue('first_name', 'n/a'),
'@last_name' => $form_state->getValue('last_name', 'n/a'),
]));
}
/**
* Callback for ajax_example_autotextfields.
*
* Selects the piece of the form we want to use as replacement markup and
* returns it as a form (renderable array).
*/
public function textfieldsCallback($form, FormStateInterface $form_state) {
return $form['textfields_container'];
}
}
Members
Title Sort descending | Modifiers | Object type | Summary |
---|---|---|---|
Autotextfields::buildForm | public | function | This form has two checkboxes which the user can check in order to then reveal the first and/or last name text fields. |
Autotextfields::getFormId | public | function | |
Autotextfields::submitForm | public | function | |
Autotextfields::textfieldsCallback | public | function | Callback for ajax_example_autotextfields. |