This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
The message
event of the Service Worker API is fired when a message is received from a service worker (ServiceWorkerMessageEvent
), or a message is received in a service worker from another context (ExtendableMessageEvent
.)
Bubbles | No |
Cancelable | No |
Target objects | ServiceWorkerContainer , or ServiceWorkerGlobalScope , depending on context. |
Interface | ServiceWorkerMessageEvent or ExtendableMessageEvent , depending on context. |
Examples
When the following code is used inside the main thread to set up a message channel between it and a service worker for sending messages between the two, the event object of onmessage
will be a ServiceWorkerMessageEvent
.
navigator.serviceWorker.ready.then(function(reg) { ... // set up a message channel to communicate with the SW var channel = new MessageChannel(); channel.port1.onmessage = function(e) { console.log(e); handleChannelMessage(e.data); } mySW = reg.active; mySW.postMessage('hello', [channel.port2]); });
Inheritance
When fired on a ServiceWorkerContainer
object, the message
event implements the ServiceworkerMessageEvent
interface, which inherits from the Event
interface — it therefore has available the properties and methods defined on both interfaces.
When fired on a ServiceWorkerGlobalScope
object, the message
event implements the ExtendableMessageEvent
interface, which inherits from the ExtendableEvent
interface — it therefore has available the properties and methods defined on both interfaces.
Specifications
Specification | Status | Comment |
---|---|---|
Service Workers The definition of 'message' in that specification. |
Working Draft | Initial definition. |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|
Basic support | 45.0 | 44.0 (44.0) | No support | 24 | No support |
Feature | Android | Android Webview | Firefox Mobile (Gecko) | Firefox OS | IE Mobile | Opera Mobile | Safari Mobile | Chrome for Android |
---|---|---|---|---|---|---|---|---|
Basic support | No support | No support | (Yes) | (Yes) | No support | ? | No support | 45.0 |