class Autotextfields

Same name in other branches
  1. 4.0.x modules/ajax_example/src/Form/Autotextfields.php \Drupal\ajax_example\Form\Autotextfields

Show textfields based on AJAX-enabled checkbox clicks.

Hierarchy

Expanded class hierarchy of Autotextfields

Related topics

1 string reference to 'Autotextfields'
ajax_example.routing.yml in modules/ajax_example/ajax_example.routing.yml
modules/ajax_example/ajax_example.routing.yml

File

modules/ajax_example/src/Form/Autotextfields.php, line 13

Namespace

Drupal\ajax_example\Form
View 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 Overriden Title Overrides
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.
Overrides FormInterface::buildForm
Autotextfields::getFormId public function Returns a unique string identifying the form. Overrides FormInterface::getFormId
Autotextfields::submitForm public function Form submission handler. Overrides FormInterface::submitForm
Autotextfields::textfieldsCallback public function Callback for ajax_example_autotextfields.
DependencySerializationTrait::$_entityStorages protected property
DependencySerializationTrait::$_serviceIds protected property
DependencySerializationTrait::__sleep public function 1
DependencySerializationTrait::__wakeup public function 2
FormBase::$configFactory protected property The config factory. 3
FormBase::$requestStack protected property The request stack. 1
FormBase::$routeMatch protected property The route match.
FormBase::config protected function Retrieves a configuration object.
FormBase::configFactory protected function Gets the config factory for this form. 3
FormBase::container private function Returns the service container.
FormBase::create public static function Instantiates a new instance of this class. Overrides ContainerInjectionInterface::create 105
FormBase::currentUser protected function Gets the current user.
FormBase::getRequest protected function Gets the request object.
FormBase::getRouteMatch protected function Gets the route match.
FormBase::logger protected function Gets the logger for a specific channel.
FormBase::redirect protected function Returns a redirect response object for the specified route.
FormBase::resetConfigFactory public function Resets the configuration factory.
FormBase::setConfigFactory public function Sets the config factory for this form.
FormBase::setRequestStack public function Sets the request stack object to use.
FormBase::validateForm public function Form validation handler. Overrides FormInterface::validateForm 73
LoggerChannelTrait::$loggerFactory protected property The logger channel factory service.
LoggerChannelTrait::getLogger protected function Gets the logger for a specific channel.
LoggerChannelTrait::setLoggerFactory public function Injects the logger channel factory.
MessengerTrait::$messenger protected property The messenger. 17
MessengerTrait::messenger public function Gets the messenger. 17
MessengerTrait::setMessenger public function Sets the messenger.
RedirectDestinationTrait::$redirectDestination protected property The redirect destination service. 1
RedirectDestinationTrait::getDestinationArray protected function Prepares a 'destination' URL query parameter for use with \Drupal\Core\Url.
RedirectDestinationTrait::getRedirectDestination protected function Returns the redirect destination service.
RedirectDestinationTrait::setRedirectDestination public function Sets the redirect destination service.
StringTranslationTrait::$stringTranslation protected property The string translation service. 3
StringTranslationTrait::formatPlural protected function Formats a string containing a count of items.
StringTranslationTrait::getNumberOfPlurals protected function Returns the number of plurals supported by a given language.
StringTranslationTrait::getStringTranslation protected function Gets the string translation service.
StringTranslationTrait::setStringTranslation public function Sets the string translation service to use. 2
StringTranslationTrait::t protected function Translates a string to the current language or to a given language.