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Ms14 trackoverlay

#1

Hi,

From the demo sample https://docs.thinkgeo.com/products/desktop-maps/quickstart-winforms/ I try to set a TrackOverlay but got the following error :
System.Collections.Generic.KeyNotFoundException: ‘The given key ‘TrackInteractiveOverlay’ was not present in the dictionary.’

here is the code, I just added the line about the trackoverlay at the end

private async void Form_Load(object? sender, EventArgs e)
{
// Set the map’s unit of measurement to meters(Spherical Mercator)
mapView.MapUnit = GeographyUnit.Meter;

// Add Cloud Maps as a background overlay
var thinkGeoCloudVectorMapsOverlay = new ThinkGeoCloudVectorMapsOverlay
{
ClientId = “AOf22-EmFgIEeK4qkdx5HhwbkBjiRCmIDbIYuP8jWbc~”,
ClientSecret = “xK0pbuywjaZx4sqauaga8DMlzZprz0qQSjLTow90EhBx5D8gFd2krw~~”,
MapType = ThinkGeoCloudVectorMapsMapType.Light,
TileCache = new FileRasterTileCache(@".\cache", “thinkgeo_vector_light”)
};
mapView.Overlays.Add(thinkGeoCloudVectorMapsOverlay);

// Set the map extent
mapView.CurrentExtent = MaxExtents.ThinkGeoMaps;

mapView.TrackOverlay = new TrackInteractiveOverlay();

await mapView.RefreshAsync();
}

I am using the last 14 beta096, this kind of code was working in MS12

#2

Hi,

Thanks for reporting this. In ThinkGeo UI 14, the TrackOverlay is automatically created inside the MapView , so you don’t need to add or manage it yourself. To enable drawing, you only need to set its TrackMode . For example:

mapView.TrackOverlay.TrackMode = TrackMode.Line;

That single line is enough to activate drawing.

If you also want to capture the shape once the user finishes drawing, you can handle the TrackEnded event like this:

mapView.TrackOverlay.TrackEnded += (s, e) =>
{
    var shape = e.TrackShape;
    // Do something with the drawn shape here
};

So the key change is:

  • Don’t add your own TrackInteractiveOverlay to the overlays collection.
  • Simply use the built-in mapView.TrackOverlay and set its TrackMode .

This way, you won’t see the KeyNotFoundException anymore, and the drawing should work immediately without needing to pan or resize.

Kind regards,
Rui

#3

Hi Rui,

Thank you for sharing the code snippet. Before V14, we used our own CustomTrackInteractiveOverlay. If I understand correctly, now I should use the built-in TrackOverlay and subscribe to its events in order to to implement my own logic, right ?

How could I achieve something similar to this :

protected override InteractiveResult MouseClickCore(InteractionArguments interactionArguments)
      {
        if (interactionArguments.MouseButton != MapMouseButton.Right)
        {
          if (MapControler.snapMode)
          {
            PointShape point = new(interactionArguments.WorldX, interactionArguments.WorldY);
            PointShape closestPoint = getClosestPointTo(point);

            if (closestPoint != null)
            {
              interactionArguments.WorldX = closestPoint.X;
              interactionArguments.WorldY = closestPoint.Y;
            }
          }

          return base.MouseClickCore(interactionArguments);
        }

        RemoveLastVertexAdded();
        return new InteractiveResult();
      }
#4

Hi Judicael,

We’ve recreated your issue and have it fixed in the latest beta, can you pull the latest (ThinkGeo.UI.WinForms 14.4.0-beta100) and have another try?

Thanks,
Ben