Problem with CheckOverlapping method in TextStyle

[Steven1]

I am upgrading from TG-10 to TG-14. The version of CheckOverlapping I was using in my CustomTextStyle class (inherits from TextStyle) has been deprecated and I cant’ seem to make the current version work. Here is the code:

      Dim oQuadTree As New Quadtree(Of SimpleCandidate)
      If CheckOverlapping(oLabelingCandidate, oCanvas, Me.Font, Me.XOffsetInPixel, Me.YOffsetInPixel, Me.RotationAngle, oQuadTree) Then
        '***** It would overlap another label so don't add it.
        Continue For
      End If

I receive the following:

System.NullReferenceException
  HResult=0x80004003
  Message=Object reference not set to an instance of an object.
  Source=ThinkGeo.Core
  StackTrace:
   at ThinkGeo.Core.PositionStyle.CheckOverlapping(LabelingCandidate labelingCandidate, GeoCanvas canvas, GeoFont font, Single xOffsetInPixel, Single yOffsetInPixel, Double rotationAngle, Quadtree`1 labelsInAllLayersIndex)
   at ThinkGeo_14_Demo.CustomTextStyle.GetLabeledFeatures(Collection`1 oAllFeatures, GeoCanvas oCanvas, Collection`1 labelsInThisLayer, Collection`1 labelsInAllLayers) in C:\Users\ZipPa\source\repos\LabelTest\CustomTextStyle.vb:line 829

I may not be using it correctly as I have never used QuadTree(of T) before. I have attached a sample project. Look in class CustomTextStyle in method GetLabeledFeatures for the exception.

Thanks,

Steve
LabelTest.zip (2.3 MB)

[Ben]

Hi Steve,

The following 2 changes on your side would make it work:

1. Set Feature (and some other properties right after GetLabelingCandidates)

	Dim oRawLabelingCandidates As Collection(Of LabelingCandidate) = GetLabelingCandidates(oFeature, FormatTemplate(Me.TextContent, oFeature.ColumnValues), oCanvas, Me.Font, XOffsetInPixel, YOffsetInPixel, RotationAngle)
	For i As Integer = 0 To oRawLabelingCandidates.Count - 1
		oRawLabelingCandidates(i).Feature = oFeature
		oRawLabelingCandidates(i).PositionStyle = Me
		oRawLabelingCandidates(i).Key = oRawLabelingCandidates(0).OriginalText & Me.GetHashCode().ToString()
	Next
...... 

These assignments are in DrawCore which were not called by you. We are going to move these code over to GetLabelingCandidates since beta080 so you will not need these workaround code in the future.

2. In the constructor of CustomLabelingCandidate, Add “Feature = oLabelingCandidate.Feature”

	Public Sub New(oLabelingCandidate As LabelingCandidate, iLabelingId As Integer)
		MyBase.New
		With oLabelingCandidate
            ......
			Feature = oLabelingCandidate.Feature
		End With
		LabelingId = iLabelingId
	End Sub

Let me know if you see more issues.

Thanks,
Ben

[Ben]

FYI: ThinkGeo.UI.WinForms 14.5.0-beta080 was just uploaded.