"object reference not set to an instance of an object" when trying to get lat, lng from a KML-layer to Google Maps [Xamarin Android] -


i working kml-file via plugin: https://github.com/sushihangover/sushihangover.android.maps.utils

the kml-file using gets added succesfully via codesnippet:

var kmllayer = new kmllayer(googlemap, resource.raw.campus, android.app.application.context); kmllayer.addlayertomap(); movecameratokml(kmllayer);

when it's added run movecameratokmlfunction try lat, lng of every point crash on row foreach (latlng latlng in ((kmllinestring)geo).geometryobject); errormessage: object reference not set instance of object

void movecameratokml(kmllayer kmllayer) {   //retrieve first container in kml layer   var container = (kmlcontainer)kmllayer.containers.iterator().next();    //retrieve nested container within first container   container = (kmlcontainer)container.containers.iterator().next();    //retrieve first placemark in nested container   var placemark = (kmlplacemark)container.placemarks.iterator().next();   var geo = placemark.geometry;   if (geo kmllinestring)   {       foreach (latlng latlng in ((kmllinestring)geo).geometryobject) //object reference not set instance of object       {          system.diagnostics.debug.writeline(latlng);        }    }  }

any idea why giving me crash? following example of nuget downloaded above.

the idea store lat, lngs in list , use polylineoptions create routes.

that google sample (movecameratokml) assumes using campus kml example. since kml use unique app, need review kml/xml elements , write code suit usage.

here example using grand canyon kml linestring hiking path:

so looking @ kml, need to:

  1. get first container
  2. get first placemark in container
  3. check if has geometry , kml linestring
  4. obtain latlng array via geometryjavaobject()
  5. use latlngs build camera viewport , move it.
  6. "drive" camera along individual points

grand canyon kmllinestring example:

void movecameratokml(kmllayer kmllayer) {     var container = (kmlcontainer)kmllayer.containers.iterator().next();     var placemark = (kmlplacemark)container.placemarks.iterator().next();     if (placemark.hasgeometry && placemark.geometry kmllinestring)     {         var linestring = placemark.geometry kmllinestring;         var latlngarray = linestring.geometryjavaobject() java.util.arraylist;         using (var builder = new latlngbounds.builder())         {             foreach (latlng latlng in latlngarray.toenumerable())             {                 builder.include(latlng);             }             googlemap.movecamera(cameraupdatefactory.newlatlngbounds(                 builder.build(), mapfragment.view.width, mapfragment.view.height, 1)             );         }         task.run(async () => // run camera along kmllinestring         {             foreach (latlng latlng in latlngarray.toenumerable())             {                 await task.delay(2000);                 runonuithread(() => googlemap.movecamera(cameraupdatefactory.newlatlng(latlng)));              }         });     } }

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