gecko-dev/services/cloudsync/CloudSyncEventSource.jsm

66 lines
1.6 KiB
JavaScript

/* 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
this.EXPORTED_SYMBOLS = ["EventSource"];
Components.utils.import("resource://services-common/utils.js");
let EventSource = function (types, suspendFunc, resumeFunc) {
this.listeners = new Map();
for each (let type in types) {
this.listeners.set(type, new Set());
}
this.suspend = suspendFunc || function () {};
this.resume = resumeFunc || function () {};
this.addEventListener = this.addEventListener.bind(this);
this.removeEventListener = this.removeEventListener.bind(this);
};
EventSource.prototype = {
addEventListener: function (type, listener) {
if (!this.listeners.has(type)) {
return;
}
this.listeners.get(type).add(listener);
this.resume();
},
removeEventListener: function (type, listener) {
if (!this.listeners.has(type)) {
return;
}
this.listeners.get(type).delete(listener);
if (!this.hasListeners()) {
this.suspend();
}
},
hasListeners: function () {
for (let l of this.listeners.values()) {
if (l.size > 0) {
return true;
}
}
return false;
},
emit: function (type, arg) {
if (!this.listeners.has(type)) {
return;
}
CommonUtils.nextTick(
function () {
for (let listener of this.listeners.get(type)) {
listener.call(undefined, arg);
}
},
this
);
},
};
this.EventSource = EventSource;