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tooltippolygongmap.net

How to add tooltip to Gmap.Net polygon?

I'm using Gmap.net great tools for enable mapping in my .net 4 desktop application. I'm adding polygons on form load event. But I can not set tooltip text for polygons.

any idea?

Solution

  • The only way to do it that I found is add a marker on the same overlay, and trigger its IsVisible property when the polygon is entered:

    var gm = new GMapControl();

GMapOverlay polyOverlay = new GMapOverlay("polygons");

List<PointLatLng> points = new List<PointLatLng>();
points.Add(new PointLatLng(53.0, 10.0));
points.Add(new PointLatLng(53.0, 11.0));
points.Add(new PointLatLng(54.0, 11.0));
points.Add(new PointLatLng(54.0, 10.0));

var polygon = new GMapPolygon(points, "mypolygon");

polygon.Fill = new SolidBrush(Color.FromArgb(50, Color.Red));
polygon.Stroke = new Pen(Color.Red, 1);
polygon.IsHitTestVisible = true;

Controls.Add(gm);
gm.Overlays.Add(polyOverlay);
polyOverlay.Polygons.Add(polygon);

polyOverlay.Markers.Add(new GMarkerCross(new PointLatLng(53.5, 10.5)) { ToolTipText = "Test me", IsVisible = false, ToolTipMode = MarkerTooltipMode.Always });

gm.OnPolygonEnter += (poly) => polyOverlay.Markers.First().IsVisible = true;
gm.OnPolygonLeave += (poly) => polyOverlay.Markers.First().IsVisible = false;

    Instead of GMarkerCross you could use a GMarkerGoogle with an empty Bitmap. Note: GMarkerGoogleType.none results in a System.ArgumentNullException when the mouse enters the polygon.