title: How to update Column children onDragComplete in flutter
body: <p>I have a layout in my flutter-web with drag and drop functionalities. Once the drag is completed, I want to show the information regarding dragged element in a Column via API.</p>
  <pre><code>child: Container(
                 padding: const EdgeInsets.all(5.0),
                 margin: const EdgeInsets.only(top: 5.0, left: 5),
                 color: Colors.white,
                 child: Single Child ScrollView(
                   child: Column(
                     children: &lt;Widget&gt;[params],
                   ),
                 )
                 //    child:widgetListtile,
                 )
  </code></pre>
  <p>I want to update the params  via</p>
  <pre><code>onDragCompleted:() {
      params=fetchAttributes(id);
  }
  </code></pre>
  <p>Please help</p>