t('A user-defined date format. See the PHP manual for available options.', array('@url' => 'http://php.net/manual/function.date.php'));
$format = $this->t('Displayed as %date_format', array('%date_format' => \Drupal::service('date.formatter')->format(REQUEST_TIME, 'custom', $value)));
return array(
'#type' => 'textfield',
'#title' => $this->t($definition->getLabel()) . ' (' . $language->getName() . ')',
'#description' => $description,
'#default_value' => $value,
'#attributes' => array('lang' => $language->getId()),
'#field_suffix' => ' ' . $format . '
',
'#ajax' => array(
'callback' => 'Drupal\config_translation\FormElement\DateFormat::ajaxSample',
'event' => 'keyup',
'progress' => array('type' => 'throbber', 'message' => NULL),
),
);
}
/**
* Ajax callback to render a sample of the input date format.
*
* @param array $form
* Form API array structure.
* @param \Drupal\Core\Form\FormStateInterface $form_state
* Form state information.
*
* @return AjaxResponse
* Ajax response with the rendered sample date using the given format. If
* the given format cannot be identified or was empty, the response will
* be empty as well.
*/
public static function ajaxSample(array $form, FormStateInterface $form_state) {
$response = new AjaxResponse();
$format_value = NestedArray::getValue($form_state->getValues(), $form_state->getTriggeringElement()['#array_parents']);
if (!empty($format_value)) {
// Format the date with a custom date format with the given pattern.
// The object is not instantiated in an Ajax context, so $this->t()
// cannot be used here.
$format = t('Displayed as %date_format', array('%date_format' => \Drupal::service('date.formatter')->format(REQUEST_TIME, 'custom', $format_value)));
// Return a command instead of a string, since the Ajax framework
// automatically prepends an additional empty DIV element for a string,
// which breaks the layout.
$response->addCommand(new ReplaceCommand('#edit-date-format-suffix', '' . $format . ''));
}
return $response;
}
}