title: flutter google map: Draw Route Line between two location
body: <p>i am trying to write simple code to draw a route line between two location on google map, i used flutter_polyline_points package for that, i wrote simple code as the follows:</p>
  
  <p><code>List&lt;PointLatLng&gt; results =  await polylinePoints.getRouteBetweenCoordinates(api_key, 38.00000000, 40.222222, 41.1111111, 45.222222222);</code></p>
  
  <p>but an exception is appeared every time i run the code which is:</p>
  
  <p>Exception has occurred.
  _Exception (Exception: RangeError (index): Invalid value: Valid value range is empty: 0)</p>
  
  <p>*** can any body tell me how i can fix the error?</p>