feat(events): pub/sub event system

demos/native/index.ts

@@ -3,7 +3,7 @@ import {Control, ControlGroup} from 'angular2/forms';
 
 import {IonicApp, App, Http} from 'ionic/ionic';
 
-import {Camera, Geolocation, Vibration, Battery, Device} from 'ionic/ionic';
+import {Camera, Geolocation, Vibration, Battery, Device, Events} from 'ionic/ionic';
 
 import {CameraPage} from 'pages/camera';
 import {BatteryPage} from 'pages/battery';
@@ -20,9 +20,27 @@ import {VibrationPage} from 'pages/vibration';
   templateUrl: 'main.html'
 })
 class MyApp {
-  constructor(app: IonicApp) {
+  constructor(app: IonicApp, events: Events) {
     this.app = app;
 
+    console.log('Events', events);
+
+    events.subscribe('user:created', (user) => {
+      console.log('User created', user);
+    })
+
+    setInterval(() => {
+      events.publish('user:created', {
+        name: 'Max Lynch',
+        id: 1
+      })
+    }, 2000);
+
+    setTimeout(() => {
+      events.unsubscribe('user:created');
+      console.log(events.channels);
+    }, 6000);
+
     this.firstPage = CameraPage;
 
     this.plugins = [

ionic/components/app/app.ts

@@ -12,6 +12,7 @@ import {ActionSheet} from '../action-sheet/action-sheet';
 import {Modal} from '../modal/modal';
 import {Popup} from '../popup/popup';
 import {FocusHolder} from '../form/focus-holder';
+import {Events} from '../../util/events';
 
 /**
  * @name IonicApp
@@ -282,6 +283,7 @@ export function ionicBootstrap(rootComponentType, config) {
       let actionSheet = new ActionSheet(app, config);
       let modal = new Modal(app, config);
       let popup = new Popup(app, config);
+      let events = new Events();
 
       // add injectables that will be available to all child components
       let appBindings = Injector.resolve([
@@ -292,6 +294,7 @@ export function ionicBootstrap(rootComponentType, config) {
         bind(ActionSheet).toValue(actionSheet),
         bind(Modal).toValue(modal),
         bind(Popup).toValue(popup),
+        bind(Events).toValue(events),
         ROUTER_BINDINGS,
         bind(LocationStrategy).toClass(HashLocationStrategy)
       ]);

ionic/ionic.ts

@@ -9,13 +9,12 @@ export * from './components'
 
 export * from './platform/platform'
 export * from './platform/registry'
-
-export * from './storage/storage'
-export * from './storage/local-storage'
-export * from './storage/sql'
+export * from './platform/plugins'
+export * from './platform/storage'
 
 export * from './util/click-block'
 export * from './util/focus'
+export * from './util/events'
 
 export * from './animations/animation'
 export * from './animations/builtins'

ionic/platform/storage.ts

@@ -0,0 +1,3 @@
+export * from './storage/storage'
+export * from './storage/local-storage'
+export * from './storage/sql'

ionic/util/events.ts

@@ -0,0 +1,71 @@
+import {Injectable} from 'angular2/angular2';
+
+/**
+ * Event is a pub/sub style event system for sending and responding to application-level
+ * events across your app.
+ */
+@Injectable()
+export class Events {
+  constructor() {
+    console.log('Events constructed');
+    this.channels = [];
+  }
+
+  /**
+   * Subscribe to an event topic. Events that get posted to that topic
+   * will trigger the provided handler.
+   *
+   * @param topic the topic to subscribe to
+   * @param handler the event handler
+   */
+  subscribe(topic, ...handlers) {
+    if(!this.channels[topic]) {
+      this.channels[topic] = [];
+    }
+    handlers.forEach((handler) => {
+      this.channels[topic].push(handler);
+    });
+  }
+
+  /**
+   * Unsubscribe the given handler from the given topic. Your handler will
+   * no longer receive events published to this topic.
+   *
+   * @param topic the topic to unsubscribe from
+   * @param handler the event handler
+   */
+  unsubscribe(topic, handler) {
+    var t = this.channels[topic];
+    if(!t) {
+      return null;
+    }
+
+    t.splice(t.indexOf(handler), 1);
+
+    // If the channel is empty now, remove it from the channel map
+    if(!t.length) {
+      delete this.channels[topic];
+    }
+
+    return true;
+  }
+
+  /**
+   * Publish an event to the given topic.
+   *
+   * @param topic the topic to publish to
+   * @param eventData the data to send as the event
+   */
+  publish(topic, ...args) {
+    var t = this.channels[topic];
+    if(!t) {
+      return null;
+    }
+
+    let responses = [];
+    t.forEach((handler) => {
+      responses.push(handler(args));
+    });
+    return responses;
+  }
+}