title: Ionic 3 not updating view
body: <p>Hi I got a function which will update after a http request to the server. It seems that the console.log show that the value has been updated but the UI is not updating unless I click on any other component(ex. input).</p>
  
  <p>This is my function:</p>
  
  <pre><code>fileTransfer.upload(this.created_image, upload_url, options)
  .then((data) =&gt; {
      console.log("success:"+data.response); //This is showing correct response
      var obj = JSON.parse(data.response);
      this.sv_value = obj.value;
      console.log(this.sv_value); //This is showing correct value
  }, (err) =&gt; {
      console.log("failure:");
  })
  </code></pre>
  
  <p>This is my view html:</p>
  
  <pre><code>    &lt;ion-row&gt;
        &lt;ion-col center width-100 no-padding&gt;
          &lt;h2&gt;{{sv_value}}&lt;/h2&gt; //This is not updated
        &lt;/ion-col&gt;
      &lt;/ion-row&gt;
  </code></pre>
  
  <p>Is there any way I can tackle this issue? Thank you</p>