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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
EventEmitter: "resource://gre/modules/EventEmitter.sys.mjs",
});
const OBSERVER_TOPIC_CREATED = "contextual-identity-created";
const OBSERVER_TOPIC_DELETED = "contextual-identity-deleted";
/**
* The ContextualIdentityListener can be used to listen for notifications about
* contextual identities (containers) being created or deleted.
*
* Example:
* ```
* const listener = new ContextualIdentityListener();
* listener.on("created", onCreated);
* listener.startListening();
*
* const onCreated = (eventName, data = {}) => {
* const { identity } = data;
* ...
* };
* ```
*
* @fires message
* The ContextualIdentityListener emits "created" and "deleted" events,
* with the following object as payload:
* - {object} identity
* The contextual identity which was created or deleted.
*/
export class ContextualIdentityListener {
#listening;
/**
* Create a new BrowsingContextListener instance.
*/
constructor() {
lazy.EventEmitter.decorate(this);
this.#listening = false;
}
destroy() {
this.stopListening();
}
observe(subject, topic) {
switch (topic) {
case OBSERVER_TOPIC_CREATED:
this.emit("created", { identity: subject.wrappedJSObject });
break;
case OBSERVER_TOPIC_DELETED:
this.emit("deleted", { identity: subject.wrappedJSObject });
break;
}
}
startListening() {
if (this.#listening) {
return;
}
Services.obs.addObserver(this, OBSERVER_TOPIC_CREATED);
Services.obs.addObserver(this, OBSERVER_TOPIC_DELETED);
this.#listening = true;
}
stopListening() {
if (!this.#listening) {
return;
}
Services.obs.removeObserver(this, OBSERVER_TOPIC_CREATED);
Services.obs.removeObserver(this, OBSERVER_TOPIC_DELETED);
this.#listening = false;
}
}