import {Injectable} from 'angular2/core' import {Subject} from 'rxjs/Subject'; @Injectable() export class SidebarStateService { // Observable string sources private _isCollapsed = new Subject(); // Observable string streams isCollapsedStream$ = this._isCollapsed.asObservable(); // Service message commands stateChanged(isCollapsed:boolean) { this._isCollapsed.next(isCollapsed) } getStateStream() { return this.isCollapsedStream$; } }