Symfony/Drupal: Event Subscribers and Event Listeners.
Following up on my talk at the DrupalCon Dublin about “The state of hooking into Drupal”, I was presenting on Hooks and Events in Drupal 8 to my colleagues when someone asked a question about the concept of event subscribers and event listeners. I didn’t have an answer then because I believed both meant the same thing, which they do (somewhat) , however here is an attempt to answer the question in a more elaborate way.
Managing Block Visibility in Drupal - 3.
Allowing or restricting the blocks’ visibility using
Managing Block Visibility in Drupal - 2.
Create a custom table and define various fields in it using
Managing Block Visibility in Drupal - 1.
All the customizations in Drupal are done using hooks.