Need help upgrading to Ionic Framework 4.0? Get assistance with our Enterprise Migration Services EXPLORE NOW

Events

Improve this doc

Events is a publish-subscribe style event system for sending and responding to application-level events across your app.

Usage

import { Events } from 'ionic-angular';

// first page (publish an event when a user is created)
constructor(public events: Events) { }

createUser(user) {
  console.log('User created!')
  this.events.publish('user:created', user, Date.now());
}


// second page (listen for the user created event after function is called)
constructor(public events: Events) {
  events.subscribe('user:created', (user, time) => {
    // user and time are the same arguments passed in `events.publish(user, time)`
    console.log('Welcome', user, 'at', time);
  });
}

Instance Members

publish(topic, eventData)

Publish an event to the given topic.

Param Type Details
topic string

the topic to publish to

eventData any

the data to send as the event

subscribe(topic, handler)

Subscribe to an event topic. Events that get posted to that topic will trigger the provided handler.

Param Type Details
topic string

the topic to subscribe to

handler function

the event handler

unsubscribe(topic, handler)

Unsubscribe from the given topic. Your handler will no longer receive events published to this topic.

Param Type Details
topic string

the topic to unsubscribe from

handler function

the event handler

Returns:

true if a handler was removed

API

Native

General