ngClass is Angular 2's way of allowing you to apply classes and styles based on what's happening in your component. While CSS covers many scenarios with pseudo classes, you'll often run into scenarios where you need to apply classes based on certain conditions, so
ngClass comes to the rescue.
Components push out events using a combination of an
@Output and an
EventEmitter. This allows a clean separation between reusable Components and application logic. This lesson shows how to use
@Output to create an update event and then listen for the even in your application.