aura:valueDestroy

This event is automatically fired when a component is being destroyed. The aura:valueDestroy event is handled by a client-side controller.

A component can have only one <aura:handler name="destroy"> tag to handle this event.

1<aura:handler name="destroy" value="{!this}" action="{!c.handleDestroy}"/>

This client-side controller handles the aura:valueDestroy event.

1({
2    handleDestroy : function (component, event, helper) {
3      var val = event.getParam("value");
4      // Do something else here
5    }
6})

Let’s say that you are viewing a component in Salesforce1. The aura:valueDestroy event is triggered when you tap on a different menu item on the Salesforce1 navigation menu, and your component is destroyed. In this example, the value parameter in the event returns the component that’s being destroyed.