The action attribute of <aura:handler> sets the client-side controller action to handle the event. The event attribute specifies the event being handled. The format is namespace : eventName . In this example, when the event is fired, the handleComponentEvent client-side controller action is called.
The action attribute of <aura:handler> sets the client-side controller action to handle the event. The event attribute specifies the event being handled. The format is namespace : eventName . In this example, when the event is fired, the handleComponentEvent client-side controller action is called.