A great feature of scopes is the ability to emit and broadcast events within the scope hierarchy. Events allow you to send notification to different levels in the scope that an event has occurred. Events can be anything you choose, such as a value changed or threshold reached. This is extremely useful in many situations, such as letting child scopes know that a value has changed in a parent scope or vice versa.
To emit an event from a scope, you use the
$emit() method. This method sends an event upward through the parent scope hierarchy. Any ancestor scopes that have registered for the event are notified. The
$emit() method uses the following syntax, where
name is the event name and
args is zero or more arguments ...