KmlLayer does not display images

NataliaEvsyuchenya

Hello!

I am try to add KmlLayer to the Map. I place kmz file at the  C:\inetpub\wwwroot\KML_TEST_FILES\. If unzip the my kmz file you can see:


[INDENT]<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://www.opengis.net/kml/2.2" xmlns:gx="http://www.google.com/kml/ext/2.2" xmlns:kml="http://www.opengis.net/kml/2.2" xmlns:atom="http://www.w3.org/2005/Atom">
<GroundOverlay>
<name>????????? ??? ????????</name>
<Icon>
  <href>files/4_9.jpg</href>
  <viewBoundScale>0.75</viewBoundScale>
</Icon>
<LatLonBox>
  <north>52.95165833333334</north>
  <south>52.70903611111112</south>
  <east>27.76611666666667</east>
  <west>27.37067500000001</west>
</LatLonBox>
</GroundOverlay>
</kml>
[/INDENT]


I add the following code to my page:

              [INDENT]  public MainPage()
  {
   InitializeComponent();
                        Map.Layers.Add(new KmlLayer()
                                                       {
                                                              Url = new Uri("http://localhost/KML_TEST_FILES/radar.kmz"),
                                                              ID = "Kml layer"
                                                        });
  }
[/INDENT]

There is no errors but image is not shown on the map. What's the problem?

DominiqueBroux

I could display image when I set for Basic Layer Url = "http://server.arcgisonline.com/ArcGIS/rest/services/ESRI_StreetMap_World_2D/MapServer" instead of "http://services.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer". But why KmlLayer depends on Basic Layer?

That rings a bell.
The extent of the images is set with the geographical coordinates found in the KML file but this extent is not the right one when your map is using projected coordinates.

In fact, KML Groundoverlays don't support autoprojection to non geographic coordinates. It's identified as a possible future enhancement but not planned at this time.

It's probably possible to project the extent by yourself (not tested and probably not that easy though):
- go through the KML layer hierachy to find all ElementLayers
- for each ElementLayer, loop on the elements
- for each element, project the extent from Geographical coordinates to Mercator

Sorry I should have thought about that sooner.