title: how to set showModalBottomSheet to full height?
body: <p>I use <code>showRoundedModalBottomSheet</code>, how can I adjust this modal height till the appbar?</p>
  <p><a href="https://i.stack.imgur.com/ilEcY.png" rel="noreferrer"><img src="https://i.stack.imgur.com/ilEcY.png" alt="enter image description here" /></a></p>