Hook

function MYMODULE_views_pre_render(ViewExecutable $view) {
 if ($view->id() == 'ABC') {
  $view->setTitle('MY CUSTOM TITLE');
 }
}

Drupal's event system allow to create triggers when an event has been happened like create a custom hook on drupal 7.

Use Event Subscriber service.

The EventSubscriber allow to execute an action on boot as hook_boot or hook_init of drupal 7.

Example.

Add meta tag from controller

Example: Add <meta http-equiv="refresh" content="30">
$data = [
  '#tag' => 'meta',
  '#attributes' => [


Drupal 8 Hook System

Officiel Documentation :

 https://api.drupal.org/api/drupal/core!modules!views!views.api.php/function/hook_views_data/8

Use multiple database conncetion with views_data() 

For that you must add 'database'

Example: