title: Get the position of one widget in relation to another
body: <p>Is there a better way to get the position of one widget in relation to another?</p>
  <pre class="lang-dart prettyprint-override"><code>GlobalKey _key = GlobalKey();
  GlobalKey _keyRoot = GlobalKey();
  RenderBox box = _key.currentContext.findRenderObject();
  Offset position = box.localToGlobal(Offset.zero);
  RenderBox box2 = _keyRoot.currentContext.findRenderObject();
  Offset position2 = box2.localToGlobal(Offset.zero);
  double x = position.dx - position2.dx;
  double y = position.dy - position2.dy;
  </code></pre>
  <p>In addition, I would like the position to be given by the bottom left corner.</p>
  <p>Have you done this before?</p>