Drupal 8 custom block (module) create twig template file

Question

I have a custom Module that creates a custom Block which has field elements.

This all works fine but I need to theme this block. I have checked the other posts on here and tried with no luck.

I have enabled twig debug and got theme suggestions. Still no luck.

Can anyone please point me in the right direction.

This is what I have so far:

my_module/my_module.module

// nothing related in here

my_module/src/Plugin/Block/myModuleBlock.php

<?php

namespace Drupal\my_module\Plugin\Block;

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

/**
 * Provides a 'ModuleBlock' block.
 *
 * @Block(
 *  id = "module_block",
 *  admin_label = @Translation("My Module"),
 * )
 */
class ModuleBlock extends BlockBase {

  public function blockForm($form, FormStateInterface $form_state) {
    $form['test'] = array(
      '#type' => 'select',
      '#title' => $this->t('test'),
      '#description' => $this->t('test list'),
      '#options' => array(
        'Test' => $this->t('Test'), 
      ),
      '#default_value' => isset($this->configuration['test']) ? $this->configuration['test'] : 'Test',
      '#size' => 0,
      '#weight' => '10',
      '#required' => TRUE,
    );    
    return $form;
  }

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

  /**
   * {@inheritdoc}
   */
  public function build() {
    $build = [];
    $build['module_block_test']['#markup'] = '<p>' . $this->configuration['test'] . '</p>';
    return $build;
  }


}

my_module/templates/block--my-module.html.twig // as suggested by twig debug

<h1>This is a test</h1>
<div id="test-widget">{{ content }}</div>

I should also note that in my my_theme.theme I have this but I don;t think its relevant:

// Add content type suggestions.
function my_theme_theme_suggestions_page_alter(array &$suggestions, array $variables) {
  if ($node = \Drupal::request()->attributes->get('node')) {
    array_splice($suggestions, 1, 0, 'page__node__' . $node->getType());
  }
}

As for what I've tried is this:

public function build() {
    return array(
      '#theme' => 'block--my-module'
    );
}

But still no go.

Any help here is very much appreciated.

UPDATE: So I just got it to work but I still need help. I moved the template block--my-module.html.twig to my theme directory and it worked.

How do I get it to work in my module directory?

Answer 1

UPDATE: So I just got it to work but I still need help. I moved the template block--my-module.html.twig to my theme directory and it worked.

How do I get it to work in my module directory?

You can create a directory called templates/ in your modules root. Place your template here.

Now let Drupal know you store the template in your module. in your_module.module add this function:

function YOUR_MODULE_theme($existing, $type, $theme, $path) {
  return array(
    'block__my_module' => array(
      'render element' => 'elements',
      'template' => 'block--my-module',
      'base hook' => 'block'
    )
  );
}

This is not tested. It´s the way it worked for my custom block.

Don´t forget to clear the cache.

Answer 2

To be able to add the twig file in your module, you need to make sure the module defines the reference, not the theme.

You can still implement hook_theme() in the module's .module file as follows:

function mymodule_theme($existing, $type, $theme, $path) {
  return [
    'mymodule_block'     => [
      'variables' => [
        // define defaults for any variables you want in the twig file
        'attributes' => [
           'class' => ['my-module-class'],
         ], //etc
      ],
    ],
  ];
}

Then in your block's build() implementation you can add a reference to the new theme function:

public function build() {
    // Load the configuration from the form
    $config = $this->getConfiguration();
    $test_value = isset($config['test']) ? $config['test'] : '';

    $build = [];
    $build['#theme'] = 'mymodule_block';

    // You would not do both of these things...
    $build['#test_value'] = $test_value;
    $build['module_block_test']['#markup'] = '<p>' . $test_value . '</p>';

    return $build;
}

Finally be careful about where you place your twig file and what you name it. Create a templates directory in your module directory, and replace the _ in the theme function name with -: mymodule-block.html.twig