The event attribute specifies the event being handled. The format is namespace:eventName.
The action attribute of <aura:handler> sets the client-side controller action to handle the event.
The handler for an application event won’t work if you set the name attribute in <aura:handler>. Use the name attribute only when you’re handling component events.
Note
In this example, when the event is fired, the handleApplicationEvent client-side controller action is called.
Event Handling Phases
The framework allows you to handle the event in different phases. These phases give you flexibility for how to best process the event for your application.
Application event handlers are associated with the default phase. To add a handler for the capture or bubble phases instead, use the phase attribute.
Get the Source of an Event
In the client-side controller action for an <aura:handler> tag, use evt.getSource() to find out which component fired the event, where evt is a reference to the event. To retrieve the source element, use evt.getSource().getElement().
Event propagation rules determine which components in the containment hierarchy can handle events by default in the bubble or capture phases. Learn about the rules and how to handle events in the bubble or capture phases.
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