title: Flutter CachedNetworkImage doesn't work, loading images again when scrolling up to bottom or bottom to up
body: <p>I'm trying to work with cached images. I followed <a href="https://flutter.dev/docs/cookbook/images/cached-images" rel="nofollow noreferrer">CachedNetworkImage</a>  but it doesn't work. Please help me if any other solution available in flutter</p>
  
  <p><a href="https://firebasestorage.googleapis.com/v0/b/ageru-f4fc9.appspot.com/o/video%2FScreenrecorder-2019-09-24-09-09-41-648.mp4?alt=media&amp;token=ac287aa7-ee2c-4382-854f-753186426b71" rel="nofollow noreferrer">Here is video of my issue</a> </p>
  
  <p>When I scrolled list from up to bottom or bottom to up the images are gone and reloaded again</p>
  
  <p>Code</p>
  
  <pre><code>        ClipRRect(
                    borderRadius: new BorderRadius.only(
                    topRight: Radius.circular(10.0),
                    topLeft: Radius.circular(10.0)),
                    child: CachedNetworkImage(
                         placeholder: (context, url) =&gt; Center(
                             child: CircularProgressIndicator(),),
                              imageUrl: productList[position]["images"]
                              ["post_image1"],
                              height: 180,
                              width: MediaQuery.of(context).size.width,
                              fit: BoxFit.cover,
                      ))
  </code></pre>