title: How to use Flutter to build a bottom sheet widget which is able to drag up to full screen?
body: <p>I want to build a bottom sheet widget which is able to drag up to full screen. </p>
  
  <p>Can anyone tell me how to do this?</p>
  
  <p>Google map has a widget is able to do this. Here is the screenshot (check attached image):</p>
  
  <p><strong>Before drag up:</strong></p>
  
  <p><a href="https://i.stack.imgur.com/5sydH.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/5sydH.jpg" alt="Bottom sheet with drag up button"></a>
  <strong>After drag up:</strong></p>
  
  <p><a href="https://i.stack.imgur.com/FvuO7.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/FvuO7.jpg" alt="Bottom sheet after drag up"></a></p>