abstract class WebMessageCallback

The listener for handling MessagePort events. The message callback methods are called on the main thread. If the embedder application wants to receive the messages on a different thread, it can do this by passing a Handler in WebMessagePort.setWebMessageCallback(WebMessageCallback,Handler). In the latter case, the application should be extra careful for thread safety since WebMessagePort methods should be called on main thread.

Summary

Public constructors
Public methods
open Unit

onMessage(port: WebMessagePort!, message: WebMessage!)

Message callback for receiving onMessage events.

Public constructors

WebMessageCallback

WebMessageCallback()

Public methods

onMessage

open fun onMessage(
    port: WebMessagePort!,
    message: WebMessage!
): Unit

Message callback for receiving onMessage events.

Parameters
port WebMessagePort!: the WebMessagePort that the message is destined for
message WebMessage!: the message from the entangled port.

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Last updated 2026-02-26 UTC.