An Aura.Action is a reference to an action in the
framework. If a child component has an Aura.Action
attribute, a parent component can pass in an action handler when it instantiates the child
component in its markup. This pattern is a shortcut to pass a controller action from a
parent component to a child component that it contains, and is used for on* handlers, such as onclick.
Although Aura.Action works for
passing an action handler to a child component, we recommend registering an event in
the child component and firing the event in the child’s controller instead. Then,
handle the event in the parent component. The event approach requires a few extra
steps in creating or choosing an event and firing it but events are the standard way
to communicate between components.
Aura.Action shouldn’t be used for other use cases. Here are some
known limitations of Aura.Action.
- Don’t use cmp.set() in JavaScript
code to reset an attribute of type="Aura.Action" after it’s previously been set. Doing so
generates an
error.
- Don’t use $A.enqueueAction() in the
child component to enqueue the action passed to the Aura.Action attribute.
Example
This example demonstrates how to pass an action handler from a parent component to a
child component.
Here’s the child component with the Aura.Action
attribute. The onclick handler for the button
uses the value of the onclick attribute, which
has type of Aura.Action.
Here’s the parent component that contains the child component in its markup.
When you click the button in c:child, the
parentAction action in the controller
of c:parent is executed.
Instead of an Aura.Action attribute, you could
use <aura:registerEvent> to register an
onclick event in the child component. You’d
have to define the event and create an action in the child’s controller to fire the
event. This event-based approach requires a few extra steps but it’s more in line
with standard practices for communicating between components.
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