title: Ionic 2: Calling Events subscribe and unsubscribe simultaneously
body: <p>I am trying to use <code>Publish</code> and <code>Subscribe</code> from ionic-angular.</p>
  
  <p><strong>subscribe.js</strong></p>
  
  <pre><code>this.events.subscribe('done:eventA', (userEventData) =&gt; {
    //Perform some operations
    this.startEventB();
    this.events.unsubscribe('done:eventA');    &lt;---
  }
  
  this.events.subscribe('done:eventB', (userEventData) =&gt; {
    //Perform some operations
    this.startEventA();
  }
  
  this.events.subscribe('done:eventA', (userEventData) =&gt; {
    //Perform some operations
    this.startEventC();
  }
  
  startEventB(){ 
    this.events.publish('done:eventB', data);
  }
  
  startEventA(){
    this.events.publish('done:eventA', data);
  }
  </code></pre>
  
  <p>The <strong>first</strong> time Event A is publish I want to perform <code>startEventB()</code><br>
  The <strong>second</strong> time Event A is publish I want to perform <code>startEventC()</code> so I tried to <code>unsubscribe</code> from the first part.<br>
  But when I <code>unsubscribe</code>, all my subscriptions are gone.   </p>
  
  <p>Can I know whats a good way to subscribe and unsubscribe from events?</p>