Cluster markers

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 Google 
 LLC 
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 , 
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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' 
 ; 
 /// 
 Defines 
 a 
 group 
 of 
 nearby 
 markers 
 as 
 a 
 cluster 
 so 
 that 
 the 
 map 
 can 
 /// 
 collapse 
 them 
 into 
 a 
 single 
 marker 
 when 
 appropriate 
 . 
 class 
  
 ClustersSample 
 extends 
 StatelessWidget 
 { 
 ClustersSample 
 ({ 
 super 
 . 
 key 
 }); 
 final 
 ClusterManager 
 _myCluster 
 = 
 ClusterManager 
 ( 
 clusterManagerId 
 : 
 ClusterManagerId 
 ( 
 'my cluster' 
 ), 
 ); 
 @override 
 Widget 
 build 
 ( 
 BuildContext 
 context 
 ) 
 { 
 return 
 GoogleMap 
 ( 
 initialCameraPosition 
 : 
 CameraPosition 
 ( 
 target 
 : 
 LatLng 
 ( 
 0 
 , 
 0 
 )), 
 // 
 You 
 have 
 to 
 supply 
 the 
 list 
 of 
 clusters 
 that 
 are 
 referred 
 to 
 // 
 by 
 the 
 map 
 's markers. 
 // 
 // 
 Note 
 : 
 For 
 clusters 
 to 
 work 
 on 
 the 
 web 
 , 
 you 
 * 
 must 
 * 
 import 
  
 an 
 additional 
 // 
 JavaScript 
 library 
 . 
 Read 
 the 
 web 
 README 
 for 
 info 
 : 
 // 
 https 
 : 
 // 
 pub 
 . 
 dev 
 / 
 packages 
 / 
 google_maps_flutter_web 
 clusterManagers 
 : 
 { 
 _myCluster 
 }, 
 markers 
 : 
 { 
 // 
 Google 
 Maps 
 will 
 smartly 
 cluster 
 markers 
 with 
 the 
 same 
 // 
 clusterManagerId 
 . 
 When 
 zoomed 
 in 
 close 
 enough 
 , 
 the 
 cluster 
 will 
 // 
 break 
 up 
 into 
 individual 
 markers 
 . 
 Marker 
 ( 
 markerId 
 : 
 MarkerId 
 ( 
 'in 1' 
 ), 
 position 
 : 
 LatLng 
 ( 
 6.51 
 , 
 3.37 
 ), 
 clusterManagerId 
 : 
 _myCluster 
 . 
 clusterManagerId 
 , 
 ), 
 Marker 
 ( 
 markerId 
 : 
 MarkerId 
 ( 
 'in 2' 
 ), 
 position 
 : 
 LatLng 
 ( 
 6.64 
 , 
 3.52 
 ), 
 clusterManagerId 
 : 
 _myCluster 
 . 
 clusterManagerId 
 , 
 ), 
 Marker 
 ( 
 markerId 
 : 
 MarkerId 
 ( 
 'in 3' 
 ), 
 position 
 : 
 LatLng 
 ( 
 6.46 
 , 
 3.58 
 ), 
 clusterManagerId 
 : 
 _myCluster 
 . 
 clusterManagerId 
 , 
 ), 
 Marker 
 ( 
 markerId 
 : 
 MarkerId 
 ( 
 'in 4' 
 ), 
 position 
 : 
 LatLng 
 ( 
 6.85 
 , 
 3.63 
 ), 
 clusterManagerId 
 : 
 _myCluster 
 . 
 clusterManagerId 
 , 
 ), 
 // 
 Markers 
 without 
 a 
 clusterManagerId 
 will 
 always 
 show 
 independently 
 . 
 Marker 
 ( 
 markerId 
 : 
 MarkerId 
 ( 
 'out' 
 ), 
 position 
 : 
 LatLng 
 ( 
 5.31 
 , 
 - 
 3.99 
 )), 
 }, 
 ); 
 } 
 } 
 
  marker_clusters 
 . 
 dart