delegate()

Delegates incoming events to methods of this object, notably from the attached view.

delegate(event: ObservableEvent): Promise<boolean | void> | boolean | void;

This method is called automatically when an event is emitted by the current view object (except if ObservableEvent.noPropagation was set on the event; see ObservableObject.attach() which is used to set up view event delegation).
The base implementation calls activity methods starting with on, e.g. onClick for a Click event. The event is passed as a single argument, and the return value should either be true (event handled), false/undefined, or a promise (which is awaited just to be able to handle any errors).

The result of the event handler method, or undefined.

class Activity
A class that represents a part of the application that can be activated when the user navigates to it.
attach() protected
Attaches the specified observable object to this object.
interface ObservableObject.EventDelegate static
A type of object that can be used to handle events from other (attached) objects.

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