title: Get http post request progress for loading indicator
body: <p>I am building an angular 2 application. In this on submit of a page I am calling web service via HTTP POST and navigating to the next screen based on the service response. </p>
  
  <p>During this I would like to show loading indicator that shows the progress of the service request. Both the i/p and o/p are of JSON format and doesn't involve any image uploading.</p>
  
  <p>Is there any way of doing this? Please help and thanks in advance.</p>