Adding autocomplete for text-field

Question

I tried to implement an autocomplete in text-field for drupal 8 in my custom module

all I wanted was to fetch and display the likely title I typed via autocomplete so declared a public function autocomplete within a class in DefaultController.php in folder directory -->mymodule/src/Controller/DefaultController.php

<?php

namespace Drupal\mymodule\Controller;

use Drupal\Core\Controller\ControllerBase;
use Symfony\Component\HttpFoundation\JsonResponse;

class DefaultController extends ControllerBase
{
    public function autocomplete($string)
    {
        $matches = array();
        $db = \Drupal::database();
        $result = $db->select('node_field_data', 'n')
        ->fields('n', array('title', 'nid'))
        ->condition('title', '%'.db_like($string).'%', 'LIKE')
        ->addTag('node_access')
        ->execute();

        foreach ($result as $row) {
            $matches[$row->nid] = check_plain($row->title);
        }

        return new JsonResponse($matches);
    }
}

then created an EditForm.php in folder directory -->mymodule/src/Form/EditForm.php

<?php

namespace Drupal\mymodule\Form;

use Drupal\Core\Form\FormBase;
use Drupal\Core\Form\FormStateInterface;

class EditForm extends FormBase
{
    public function getFormId()
    {
        return 'mymodule_edit_form';
    }

    public function buildForm(array $form, FormStateInterface $form_state)
    {
        $form = array();

  $form['input_fields']['nid'] = array(
    '#type' => 'textfield',
    '#title' => t('Name of the referenced node'),
    '#autocomplete_route_name' => 'mymodule.autocomplete',
    '#description' => t('Node Add/Edit type block'),
    '#default' => ($form_state->isValueEmpty('nid')) ? null : ($form_state->getValue('nid')),
    '#required' => true,
  );

        $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Create'),
  );

        return $form;
    }
}

also created mymodule.routing.yml

  mymodule.autocomplete:
  path: '/mymodule/autocomplete'
  defaults:
    _controller: '\Drupal\mymodule\Controller\DefaultController::autocomplete'
  requirements:
    _permission: 'access content'

still autocomplete functionality not getting implemented ? Can anybody point me what am i missing ??

Answer 1

Your class need some modification you need to check request and put it into $string.

<?php

namespace Drupal\mymodule\Controller;

use Symfony\Component\HttpFoundation\JsonResponse;
use Symfony\Component\HttpFoundation\Request;
use Drupal\Component\Utility\Unicode;

class DefaultController extends ControllerBase
{

  /**
   * Returns response for the autocompletion.
   *
   * @param \Symfony\Component\HttpFoundation\Request $request
   *   The current request object containing the search string.
   *
   * @return \Symfony\Component\HttpFoundation\JsonResponse
   *   A JSON response containing the autocomplete suggestions.
   */

  public function autocomplete(request $request) {
    $matches = array();
    $string = $request->query->get('q');
    if ($string) {
      $matches = array();
      $query = \Drupal::entityQuery('node')
      ->condition('status', 1)
      ->condition('title', '%'.db_like($string).'%', 'LIKE');
      //->condition('field_tags.entity.name', 'node_access');
      $nids = $query->execute();
      $result = entity_load_multiple('node', $nids);
      foreach ($result as $row) {
        //$matches[$row->nid->value] = $row->title->value;
        $matches[] = ['value' => $row->nid->value, 'label' => $row->title->value];
      }
    }
    return new JsonResponse($matches);
  }
}

Answer 2

If you want to select an entity, then there is a way easier way to do that. Drupal 8 has a standard entity_autocomplete field type, just specify your form element like this:

$form['node'] = [
  '#type' => 'entity_autocomplete',
  '#target_type' => 'node',
];

See Custom autocomplete field for more information.

Also, never do database queries against node/entity tables. Use \Drupal::entityQuery() for that.

Answer 3

1. Create a routing.yml file and add the below code : admin_example.autocomplete:

:

  path: '/admin_example/autocomplete'
  defaults:
    _controller: '\Drupal\admin_example\Controller\AdminNotesController::autocomplete'
  requirements:
    _permission: 'access content'

2. The form which you have build in mymodule/src/Form/EditForm.php is correct

You need to change the code in controller .The code is below :

public function autocomplete(Request $request)
{
 $string = $request->query->get('q');
    $matches = array();
      $query = db_select('node_field_data', 'n')
          ->fields('n', array('title', 'nid'))
          ->condition('title', $string . '%', 'LIKE')
          ->execute()
          ->fetchAll();
    foreach ($query as $row) {
        $matches[] = array('value' => $row->nid, 'label' => $row->title);
    }

    return new JsonResponse($matches);
}

Answer 4

Use @vgoradiya code then on the foreach loop try it this way:

    foreach ($result as $row)
    {
        $matches[] = ['value' => $row->nid, 'label' => check_plain($row->title)];
    }

Answer 5

FWIW I had the same need and was greatly helped by the excellent write-up over at https://antistatique.net/en/blog/how-to-create-a-custom-autocomplete-entity-field-widget-using-the-drupal-8-form-api