'range', '#min' => 10, '#max' => 5, '#title' => 'Invalid range', '#description' => 'Minimum greater than maximum.', ]; $form['submit'] = [ '#type' => 'submit', '#value' => 'Submit', ]; return $form; } /** * {@inheritdoc} */ public function submitForm(array &$form, FormStateInterface $form_state) { } }