Custom handle bs-dropdown event in Ember component

In an Ember component, I have nested bs-input fields inside a bs-dropdown and would like to autofocus on one of the input fields when the dropdown is toggled on.

From what I've read, I need to attach the "shown.bs.dropdown" event to the dropdown element, but how and where do I attach it in my Ember component?

Code below:

  
    Toggle Dropdown