title: Drag and Drop asynchronous data fetching
body: <p>I am trying to implement Drag and Drop into my application which shares images.</p>
  
  <p>All my images are high performance thumbnails (i.e. small size) so I can't use them as my <code>UIDragItem</code>, at least not as the final image.</p>
  
  <p>What I am looking for is a way of providing the URL for my original image and send that off as the <code>UIDragItem</code> and then have the destination fetch the image asynchronously. This is done in the Photos app when an image is stored in iCloud, so it must somehow be possible, I just cant seem to figure out how.</p>