Over time, I have created some contributed module projects for D7. With D7 EOL not too distant in the future, I need to convert those to D8.

I've just started out doing this, and I've found the OO-style of D8 very different from the procedural style of D7.

For instance, I want to call the public function getTopics() that is part of the Advanced Help project. It can be found inside a file src/AdvancedHelpManager.php, and looks like this:

class AdvancedHelpManager extends DefaultPluginManager {

   * Search the system for all available help topics.
   * @todo check visibility of the method.
  public function getTopics() {
    $ini = $this->parseHelp();
    return $ini['topics'];

I want to call it from my module, in order to get hold of the list of topics I expect it to return.

So far, I've tried:

$foo = new AdvancedHelpManager();
$bar = $foo->getTopics();

but this returns the error "Error: Class 'AdvancedHelpManager' not found.

I guess I need to put some sort of "use"-statement on top of the file I try to use it, to make the class visible, but I am currently unable to figure out what that statement should be.

1 Answer 1


Your current code doesn't work because of namespaces, but even so, that's not the right way to approach your requirement.

AdvancedHelpManager is a plugin manager, which is a service, so you should get the instance of it like so:

$plugin_manager = \Drupal::service('plugin.manager.advanced_help');
$topics = $plugin_manager->getTopics();

(as always, if you're in a context where DI is available, inject the service instead of calling the static \Drupal method).

If any of this doesn't make sense it would be a very good idea to read the Services and dependency injection docs, which help to explain the architecture behind Drupal 8.

  • 1
    Thanks a lot! I've spent the better part of the day trying to figure out that. I understand that D8 requires a completely different mindset compared to D7. Thanks for the reading recommendation! Commented Jul 23, 2019 at 14:38
  • You're welcome. Yeah if you're coming from procedural PHP and D7, D8 can be pretty daunting, there are so many new concepts to learn. I found reading the change records really useful when I was getting in to D8, they're a good way to get a running explanation of what changed to what, and importantly why it changed
    – Clive
    Commented Jul 23, 2019 at 18:48

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