title: ObjectUnsubscribedError: object unsubscribed error when I am using ngx-progress in angular 2
body: <p>I am using <a href="https://www.npmjs.com/package/ngx-progressbar" rel="noreferrer">ngx-progressbar</a> bar in Angular 2 application. When app loading first it is working fine. second time it is showing error. I referred few article like <a href="https://medium.com/@fsufitch/angular-2-objectunsubscribederror-woes-abda60e04cfe" rel="noreferrer">medium.com</a> for subscribe object. I did't get clearly.
  I need to make progress bar every time when click the router links.</p>
  
  <p><strong>I attached error snapshot:</strong>
  <a href="https://i.stack.imgur.com/iouni.png" rel="noreferrer"><img src="https://i.stack.imgur.com/iouni.png" alt="enter image description here"></a></p>
  
  <p><strong>progress bar code:</strong></p>
  
  <pre><code>import { Component, AfterContentInit} from '@angular/core';
  import { NgProgress } from 'ngx-progressbar'
  @Component({
    selector: 'link-outlet',
    template: '&lt;ng-progress [showSpinner]="false"&gt;&lt;/ng-progress&gt;'
  })
  export class RoutingDirectiveComponent implements AfterContentInit{
    constructor(private ngProgress: NgProgress) {
  
    }
    ngAfterContentInit(){
  
     this.ngProgress.start();
     setTimeout(()=&gt;{
       this.ngProgress.done();
     }, 2000);
    }
   }
  </code></pre>
  
  <p>Your suggestion will be grateful.</p>