class RobotDeleteForm

class RobotDeleteForm extends EntityConfirmFormBase {
    
    /**
     * Gathers a confirmation question.
     *
     * The question is used as a title in our confirm form. For delete confirm
     * forms, this typically takes the form of "Are you sure you want to
     * delete...", including the entity label.
     *
     * @return string
     *   Translated string.
     */
    public function getQuestion() {
        return $this->t('Are you sure you want to delete robot %label?', [
            '%label' => $this->entity
                ->label(),
        ]);
    }
    
    /**
     * Gather the confirmation text.
     *
     * The confirm text is used as the text in the button that confirms the
     * question posed by getQuestion().
     *
     * @return string
     *   Translated string.
     */
    public function getConfirmText() {
        return $this->t('Delete Robot');
    }
    
    /**
     * Gets the cancel URL.
     *
     * Provides the URL to go to if the user cancels the action. For entity
     * delete forms, this is typically the route that points at the list
     * controller.
     *
     * @return \Drupal\Core\Url
     *   The URL to go to if the user cancels the deletion.
     */
    public function getCancelUrl() {
        return new Url('entity.robot.list');
    }
    
    /**
     * The submit handler for the confirm form.
     *
     * For entity delete forms, you use this to delete the entity in
     * $this->entity.
     *
     * @param array $form
     *   An associative array containing the structure of the form.
     * @param \Drupal\Core\Form\FormStateInterface $form_state
     *   An associative array containing the current state of the form.
     */
    public function submitForm(array &$form, FormStateInterface $form_state) {
        // Delete the entity.
        $this->entity
            ->delete();
        // Set a message that the entity was deleted.
        $this->messenger()
            ->addMessage($this->t('Robot %label was deleted.', [
            '%label' => $this->entity
                ->label(),
        ]));
        // Redirect the user to the list controller when complete.
        $form_state->setRedirectUrl($this->getCancelUrl());
    }

}