Draw polylines on a map

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 Google 
 LLC 
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 License 
 , 
 Version 
 2.0 
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 the 
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 ); 
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 import 
  
 'package:flutter/material.dart' 
 ; 
 import 
  
 'package:google_maps_flutter/google_maps_flutter.dart' 
 ; 
 /// 
 Displays 
 a 
 map 
 of 
 the 
 North 
 Atlantic 
 Ocean 
 with 
 the 
 route 
 of 
 the 
 Titanic 
 /// 
 marked 
 on 
 it 
 . 
 class 
  
 PolylinesSample 
 extends 
 StatelessWidget 
 { 
 const 
 PolylinesSample 
 ({ 
 super 
 . 
 key 
 }); 
 @override 
 Widget 
 build 
 ( 
 BuildContext 
 context 
 ) 
 { 
 return 
 GoogleMap 
 ( 
 initialCameraPosition 
 : 
 CameraPosition 
 ( 
 target 
 : 
 LatLng 
 ( 
 49 
 , 
 - 
 23 
 )), 
 polylines 
 : 
 { 
 Polyline 
 ( 
 // 
 Polyline 
 id 
 must 
 be 
 unique 
 . 
 polylineId 
 : 
 PolylineId 
 ( 
 'titanic route' 
 ), 
 points 
 : 
 [ 
 LatLng 
 ( 
 50.90 
 , 
 - 
 1.41 
 ), 
 // 
 Southampton 
 LatLng 
 ( 
 49.65 
 , 
 - 
 1.60 
 ), 
 // 
 Cherbourg 
 LatLng 
 ( 
 49.77 
 , 
 - 
 6.71 
 ), 
 LatLng 
 ( 
 51.83 
 , 
 - 
 8.28 
 ), 
 // 
 Cobh 
 LatLng 
 ( 
 50.96 
 , 
 - 
 8.58 
 ), 
 LatLng 
 ( 
 41.75 
 , 
 - 
 49.90 
 ), 
 // 
 Wreck 
 ], 
 width 
 : 
 5 
 , 
 color 
 : 
 Colors 
 . 
 red 
 , 
 geodesic 
 : 
 true 
 , 
 // 
 Custom 
 caps 
 and 
 joint 
 types 
 aren 
 't supported on all platforms. 
 startCap 
 : 
 Cap 
 . 
 roundCap 
 , 
 endCap 
 : 
 Cap 
 . 
 roundCap 
 , 
 jointType 
 : 
 JointType 
 . 
 round 
 , 
 consumeTapEvents 
 : 
 true 
 , 
 onTap 
 : 
 () 
 = 
> debugPrint 
 ( 
 'clicked route' 
 ), 
 ), 
 }, 
 ); 
 } 
 } 
 
  polylines 
 . 
 dart