user controls - How to prevent a map from panning while dragging on it. Windows 10 universal application with C# -


i developing windows 10 universal application c# in witch have map pin. want pin can dragged on map , prevent map panning while drag pin. problem following code map trembling while dragging pin. code dragging following: 

protected async override void onnavigatedto(navigationeventargs e)     {         gs = (gsforcorrection)e.parameter;          try         {             string latstring = gs.latitude;             string longstring = gs.longitude;              if (gs.latitude.contains('.'))                 latstring = gs.latitude.replace('.', ',');              if (gs.longitude.contains('.'))                 longstring = gs.longitude.replace('.', ',');              double lat, lon;              bool islatok = double.tryparse(latstring, out lat);             bool islonok = double.tryparse(longstring, out lon);              if (gs != null && (islatok == islonok) == true)             {                 geopoint center = new geopoint(new basicgeoposition() { latitude = lat, longitude = lon });                  dragablepin pin = new dragablepin(mymap);                 mapcontrol.setlocation(pin, center);                 mapcontrol.setnormalizedanchorpoint(pin, new point(0.5, 1));                  pin.draggable = true;                  pin.dragend += pin_dragend;                  mymap.children.add(pin);                  await mymap.trysetviewasync(center, 17);             }         }         catch (nullreferenceexception) { }     }      private void pin_dragend(geopoint obj)     {         dragged = true;         newlat = obj.position.latitude.tostring("00.0000000");         newlong = obj.position.longitude.tostring("00.0000000");     }

the pin user control following code behind.

public sealed partial class dragablepin : usercontrol {     private mapcontrol _map;     private bool isdragging = false;     geopoint _center;      public dragablepin(mapcontrol map)     {         this.initializecomponent();         _map = map;     }      public bool draggable { get; set; }      public action<geopoint> drag;      public action<geopoint> dragstart;      public action<geopoint> dragend;      protected override void onpointerpressed(pointerroutedeventargs e)     {         base.onpointerpressed(e);          if (draggable)         {             if (_map != null)             {                 _center = _map.center;                  //attach events map track touch , movement events                 _map.actualcamerachanged += _map_actualcamerachanged;                 _map.pointerreleased += _map_pointerreleased;                 _map.pointermoved += _map_pointermoved;             }              var pointerposition = e.getcurrentpoint(_map);              geopoint location = null;             _map.getlocationfromoffset(pointerposition.position, out location);              if (location!=null)             {                 mapcontrol.setlocation(this, location);             }              if(dragstart!=null)             {                 dragstart(location);             }              //enable dragging             this.isdragging = true;         }     }       private void _map_pointermoved(object sender, pointerroutedeventargs e)     {         //check if user dragging pushpin          if(this.isdragging)         {             // if so, move pushpin pointer is.             var pointerposition = e.getcurrentpoint(_map);              geopoint location = null;             _map.getlocationfromoffset(pointerposition.position, out location);              if (location != null)             {                 mapcontrol.setlocation(this, location);             }              if(drag!=null)             {                 drag(location);             }         }     }      private void _map_pointerreleased(object sender, pointerroutedeventargs e)     {         //pushpin released, remove dragging events         if (_map != null)         {             _map.actualcamerachanged -= _map_actualcamerachanged;             _map.pointerreleased -= _map_pointerreleased;             _map.pointermoved -= _map_pointermoved;         }          var pointerposition = e.getcurrentpoint(_map);         geopoint location = null;          _map.getlocationfromoffset(pointerposition.position, out location);          if (location != null)         {             mapcontrol.setlocation(this, location);         }          if(dragend!=null)         {             dragend(location);         }          this.isdragging = false;     }      private void _map_actualcamerachanged(mapcontrol sender, mapactualcamerachangedeventargs args)     {         //reset map center stored center value.         //this prevents map panning when drag across it.         if (isdragging)         {            _map.center = _center;         }     } }

i trying prevent map panning on last part of pins code, in _map_actualcamerachanged() method resetting map's center.

how can avoid maps brembling?


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