topic Re: EditGeometry Rotation on Rectangle Causes NullReferenceException in ArcGIS Runtime SDK for WPF (Retired) Questions

EditGeometry Rotation on Rectangle Causes NullReferenceException

RyanCoodey — Thu, 17 May 2012 01:53:18 GMT

If I create a DrawMode.Rectangle graphic, start an EditGeometry on it, move the rectangle, then try and rotate it... it throws a NullReferenceException.

If I don't move the rectangle first, the rotation works fine. But after moving the rectangle, then rotating it crashes. This does not seem to happen for any of the other DrawMode types... just the rectangle.

Is this a known bug? Any workarounds?

I am running version 2.4 of the WPF API on .NET 4.

Thanks a lot for any info!

*UPDATE - The rectangle's Graphic.Geometry is of type Envelope... all others are of type Polygon. So seems the problem is with rotating envelopes after a move.

Re: EditGeometry Rotation on Rectangle Causes NullReferenceException

JenniferNery — Thu, 17 May 2012 18:23:29 GMT

Actually, Rotation should not be enabled for Envelope geometry.

If however, you converted Envelope to Polygon, just as this code does:

   var env = e.Graphic.Geometry as Envelope;    Polygon p = new Polygon() { SpatialReference = env.SpatialReference };    PointCollection ring = new PointCollection();    ring.Add(new MapPoint(env.XMin, env.YMin));    ring.Add(new MapPoint(env.XMin, env.YMax));    ring.Add(new MapPoint(env.XMax, env.YMax));    ring.Add(new MapPoint(env.XMax, env.YMin));    ring.Add(new MapPoint(env.XMin, env.YMin));    p.Rings.Add(ring);    e.Graphic.Geometry = p;

I still did not get NullReference after rotate.

Re: EditGeometry Rotation on Rectangle Causes NullReferenceException

RyanCoodey — Thu, 17 May 2012 19:50:56 GMT

Cool, thanks Jennifer... silly me didn't even think to convert it from an envelope to a polygon, but that worked great!

As far as reproducing the error, did you move the envelope around first? Because the rotate does work until you move it around. I can make this happen with this Silverlight example too: http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#DrawGraphics. Create a rectangle, start editing, move the rectangle, then rotate it. It doesn�??t throw an error in the example that I can see, but the rectangle does disappear and act up.

Thanks again!

Re: EditGeometry Rotation on Rectangle Causes NullReferenceException

JenniferNery — Thu, 17 May 2012 21:05:42 GMT

You're right the issue probably exist in v2.4.

It seems fixed in v3.0 Pre-release sample: http://resourcesbeta.arcgis.com/en/help/silverlight-api/samples/start.htm#DrawGraphics