Implements \Drupal\Core\Form\FormInterface::buildForm().
Overrides FormInterface::buildForm
public function buildForm(array $form, array &$form_state, $arg = NULL) {
$form['element'] = array(
'#markup' => 'The FormTestArgumentsObject::buildForm() method was used for this form.',
);
$form['bananas'] = array(
'#type' => 'textfield',
'#default_value' => check_plain($arg),
'#title' => t('Bananas'),
);
$form['actions']['#type'] = 'actions';
$form['actions']['submit'] = array(
'#type' => 'submit',
'#value' => t('Save'),
);
return $form;
}