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TrackMode not starting until map extent change

#1

Hi,

I use this basic code to draw shapes. The only difference between this and your HowDoI samples is that I use an override on the TrackInteractiveOverlay to define a start and end vertices for a measuring tool.

The problem I am seeing is that once this code is run, if I click the map, the drawing doesn’t begin. Only when I pan or zoom on the map does the TrackMode actual start. Any ideas what is missing from the track overlay to get it to initialize?

CustomTrackInteractiveOverlay track = new CustomTrackInteractiveOverlay();

        WinMap.TrackOverlay = track;
        track.TrackShapeLayer.ZoomLevelSet = GeoHelper.SetZoomLevels(WinMap.ZoomLevelSet,
            track.TrackShapeLayer.ZoomLevelSet.ZoomLevel01.DefaultAreaStyle);
        track.TrackShapeLayer.FeatureSource.ProjectionConverter = new GdalProjectionConverter(FromCRS.Proj4, FromCRS.Proj4);

        if (WinMap.EditOverlay.GetType() == typeof(SnapOverlay))
        {
            track.TrackStarting += Track_TrackStarting;
            track.TrackEnding += Track_TrackEnding;
            track.VertexAdding += Track_VertexAdding;
        }

        // There is always track ended
        track.TrackEnded += Track_TrackEnded;

        switch (shapeType)
        {
            case WellKnownType.GeometryCollection:
                break;
            case WellKnownType.Invalid:
                break;
            case WellKnownType.Line:
                WinMap.TrackOverlay.TrackMode = TrackMode.StraightLine;
                track.TrackShapeLayer.ZoomLevelSet = GeoHelper.SetZoomLevels(WinMap.ZoomLevelSet,
                    GeoHelper.DefaultLineStyle);
                break;
            case WellKnownType.Multiline:
                WinMap.TrackOverlay.TrackMode = TrackMode.Line;
                track.TrackShapeLayer.ZoomLevelSet = GeoHelper.SetZoomLevels(WinMap.ZoomLevelSet,
                    GeoHelper.DefaultLineStyle);
                break;
            case WellKnownType.Multipoint:
                WinMap.TrackOverlay.TrackMode = TrackMode.Point;
                track.TrackShapeLayer.ZoomLevelSet = GeoHelper.SetZoomLevels(WinMap.ZoomLevelSet,
                    GeoHelper.DefaultPointStyle);
                break;
            case WellKnownType.Multipolygon:
                WinMap.TrackOverlay.TrackMode = TrackMode.Polygon;
                track.TrackShapeLayer.ZoomLevelSet = GeoHelper.SetZoomLevels(WinMap.ZoomLevelSet,
                    GeoHelper.DefaultAreaStyle);
                break;
            case WellKnownType.Point:
                WinMap.TrackOverlay.TrackMode = TrackMode.Point;
                // Points don't support track starting or vertex adding
                track.TrackStarting -= Track_TrackStarting;
                track.VertexAdding -= Track_VertexAdding;
                track.TrackShapeLayer.ZoomLevelSet = GeoHelper.SetZoomLevels(WinMap.ZoomLevelSet,
                    GeoHelper.DefaultPointStyle);
                break;
            case WellKnownType.Polygon:
                WinMap.TrackOverlay.TrackMode = TrackMode.Polygon;
                track.TrackShapeLayer.ZoomLevelSet = GeoHelper.SetZoomLevels(WinMap.ZoomLevelSet,
                    GeoHelper.DefaultAreaStyle);
                break;
            default:
                break;
        }

        WinMap.TrackOverlay.RefreshAsync();
#2

Do you mean it will not have any issue if using the built in TrackInteractiveOverlay instead of CustomTrackInteractiveOverlay?

In that case, can you send us the source code of CustomTrackInteractiveOverlay?

#3

Based on that thought, I did the following to the top of the code so I was not using the Custom overlay to see if the problem would resolve itself

        TrackInteractiveOverlay track = WinMap.TrackOverlay;

        //CustomTrackInteractiveOverlay track = new CustomTrackInteractiveOverlay();
        //WinMap.TrackOverlay = track;

Quite unexpectedly, it all seems to have gone haywire. I click the screen and no shape is being drawn, but I see a ton of errors going off in my diagnostics.

image

#4

I just changed to this

TrackInteractiveOverlay track = new TrackInteractiveOverlay();
WinMap.TrackOverlay = track;

I no longer get all the exceptions and I can see the line being drawn on the map, but the problem with TrackMode not starting until I zoom or pan persists.

#5

I couldn’t recreate the issue, but if you haven’t called mapView.RefreshAsync() before, can you call WinMap.RefreshAsync(WinMap.TrackOverlay); instead of WinMap.TrackOverlay.RefreshAsync();? I mentioned in another post that MapView.RefreshAsync() did some overlay initialization?

#6

Hi Ben,

WinMap.RefreshAsync(WinMap.TrackOverlay) seems to have worked. Thanks!

I will have to keep in mind the two refresh methods do somewhat different things…

#7

That’s Great! :grinning: