title: Android Communication between activities
body: <p>I know the questions sounds very familiar on SO but I have different problem here is what I want to do.</p>
  
  <ol>
  <li>Store Activity where user selects an item </li>
  <li>Buy Activity here user will buy the selected item and calls downloader class and finish itself.</li>
  <li>Downloader class here I download the content and from here I have to update progress bar on Store activity </li>
  </ol>
  
  <p>*<em>EDIT :</em>*I am able to accomplish 1st and 2nd point but not 3rd one.</p>
  
  <p>I searched a lot but didn't found a solution, any ideas how to accomplish this.</p>