Adding map items at runtime does not update the map area

Hello,

if I add a polyline to the dxMapControl with OpenStreetMap provider, the map does not show the polyline until I scroll the map.

C#
procedure TForm2.Button1Click(Sender: TObject);  
var AItemLayer : TdxMapItemLayer;  
    APolyline : TdxMapPolyline;  
    APoint : TdxMapControlGeoPointItem;  
begin  
  dxMapControl1.Layers.BeginUpdate;  
  AItemLayer := dxMapControl1.AddItemLayer;  
  AItemLayer.MapItems.BeginUpdate;  
  AItemLayer.ItemStyle.BorderColor := dxColorToAlphaColor(clBlue);  
  APolyline := TdxMapPolyline(AItemLayer.AddItem(TdxMapPolyline));  
  APolyline.Style.BorderColor := dxColorToAlphaColor(clBlue);  
  APolyline.GeoPoints.BeginUpdate;  
  APoint := APolyline.GeoPoints.Add;  
  APoint.Latitude := 52;  
  APoint.Longitude := 8;  
  APoint := APolyline.GeoPoints.Add;  
  APoint.Latitude := 51;  
  APoint.Longitude := 7;  
  APolyline.GeoPoints.EndUpdate;  
  AItemLayer.MapItems.EndUpdate;  
  //dxMapControl1.Layers.UpdateViewPort;  
  dxMapControl1.Layers.EndUpdate;  
end;  

If I call dxMapControl1.Layers.UpdateViewPort the polyline shows up immediately, but I think this is not the supposed way. Am I missing something?

Best regards

Philipp