Hi Xamlmax,
Could you, please, clarify what does "dummy map source" means? The empty provider don't show any map tiles. It just provides spatial reference (projection) for other operations (i.e. show KML or ESRI shape files). If you need to show map tiles offline then you should create your own tile server which will run on the localhost.
It is quite simple to create tile server on localhost when you have images which can be identified by the zoom level and (x,y) position of the tile. All that you need to do is put your tiles in a separate directory in the C:\inetpub\wwwroot folder. So if you have the OpenStreet map tiles organized in a way similar to the structure on the OpenStreet servers (zoom\x_pos\y_pos.png) then you can create tile server on localhost in a couple of steps:
1. Create new folder like "os_images" in the "C:\inetpub\wwwroot" folder.
2. Copy whole structure of the OpenStreet images to this new folder.
Now you can create new map tile source and map provider which will access images from this folder:
/// <summary>
/// Tile source which read map tiles from the file system.
/// </summary>
public class LocalhostTileSource : TiledMapSource
{
private string tileUriFormat;
/// <summary>
/// Initializes a new instance of the FileSystemTileSource class.
/// </summary>
/// <param name="tileUriFormat">Format string to access tiles on the localhost.</param>
public LocalhostTileSource(string tileUriFormat)
: base(1, 20, 256, 256)
{
this.tileUriFormat = tileUriFormat;
}
/// <summary>
/// Initialize provider.
/// </summary>
public override void Initialize()
{
// Raise provider intialized event.
this.RaiseIntializeCompleted();
}
/// <summary>
/// Gets the image URI.
/// </summary>
/// <param name="tileLevel">Tile level.</param>
/// <param name="tilePositionX">Tile X.</param>
/// <param name="tilePositionY">Tile Y.</param>
/// <returns>URI of image.</returns>
protected override Uri GetTile(int tileLevel, int tilePositionX, int tilePositionY)
{
int zoomLevel = ConvertTileToZoomLevel(tileLevel);
string url = this.tileUriFormat.Replace("{zoom}", zoomLevel.ToString(CultureInfo.InvariantCulture));
url = url.Replace("{x}", tilePositionX.ToString(CultureInfo.InvariantCulture));
url = url.Replace("{y}", tilePositionY.ToString(CultureInfo.InvariantCulture));
return new Uri(url);
}
}
/// <summary>
/// Map provider which read map tiles from the file system.
/// </summary>
public class LocalhostProvider : TiledProvider
{
/// <summary>
/// Initializes a new instance of the LocalhostProvider class.
/// </summary>
/// <param name="tileUriFormat">Format string to access tiles on the localhost.</param>
public LocalhostProvider(string tileUriFormat)
: base()
{
LocalhostTileSource source = new LocalhostTileSource(tileUriFormat);
this.MapSources.Add(source.UniqueId, source);
}
/// <summary>
/// Returns the SpatialReference for the map provider.
/// </summary>
public override ISpatialReference SpatialReference
{
get
{
return new MercatorProjection();
}
}
}
Now you can use new map provider in your application:
The
ConvertTileToZoomLevel method is inherited from TiledMapSource class so you don't need to bother about its implementation.
Kind regards,
Andrey Murzov
the Telerik team
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