For this blog post we want to create a custom block plugin with additional configuration settings.

For this post, our main focus will be on making the custom plugin configuration translatable.
There is loads of information on creating custom block plugins, so we will not go in to deep on that.

Maak een MyCustomBlock.php bestand aan bij mymodule/src/Plugin/Block

<?php

namespace Drupal\mymodule\Plugin\Block;

use Drupal\Core\Block\BlockBase;
use Drupal\Core\Form\FormStateInterface;

/**
 * Provides a custom block.
 *
 * @Block(
 *   id = "my_custom_block",
 *   admin_label = @Translation("My custom block")
 * )
 */
class MyCustomBlock extends BlockBase {

  /**
   * {@inheritdoc}
   */
  public function defaultConfiguration() {
    return array(
      'my_favorite_drink' => $this->t('My favorite drink'),
      );
  }

  /**
   * {@inheritdoc}
   */
  public function blockForm($form, FormStateInterface $form_state) {
    $form['my_favorite_drink'] = array(
      '#type' => 'textfield',
      '#title' => $this->t('My favorite drink'),
      '#description' => $this->t('What would you like to drink?'),
      '#default_value' => $this->configuration['my_favorite_drink'],
    );

    return $form;
  }

  /**
   * {@inheritdoc}
   */
  public function blockSubmit($form, FormStateInterface $form_state) {
    $this->configuration['my_favorite_drink'] = $form_state->getValue('my_favorite_drink');
  }

  /**
   * {@inheritdoc}
   */
  public function build() {
    $block = array();

    if ($this->configuration['my_favorite_drink']) {
      $block['label'] = array(
        '#type' => 'markup',
        '#markup' => $this->configuration['my_favorite_drink'],
      );
    }

    return $block;
  }
}