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NullReference-Exception on removing treenode

Hello,

I have some difficulties using your Xamarin TreeView (both Android and IOS).

After creating a simple TreeView and adding several nodes at root level, , I tried to delete the uppermost node through code (in response to a button being pressed).

For a certain configuration that always ends in a null-reference exception.

I have attached a sample solution to demonstrate the issue.

I am not sure, what I am doing wrong here. Can you help me with that problem?


Stacktrace (IOS):

  at Syncfusion.TreeView.Engine.TreeNodesTraversalHelper.GetPrevious (Syncfusion.TreeView.Engine.TreeViewNode node) [0x00063] in <6dbcbdaf923d4f9eadae54ba4284f40f>:0

  at Syncfusion.TreeView.Engine.TopLevelNode.GetNodeAt (System.Int32 index) [0x00054] in <6dbcbdaf923d4f9eadae54ba4284f40f>:0

  at Syncfusion.TreeView.Engine.TopLevelNode.get_Item (System.Int32 index) [0x00000] in <6dbcbdaf923d4f9eadae54ba4284f40f>:0

  at Syncfusion.iOS.TreeView.LinearLayout.EnsureItems (Syncfusion.GridCommon.ScrollAxis.VisibleLinesCollection visibleLines) [0x0011c] in <8b31fbf5b8524988a341a019ad70d9e6>:0

  at Syncfusion.iOS.TreeView.TreeNodesContainerBase.EnsureItems () [0x0001b] in <8b31fbf5b8524988a341a019ad70d9e6>:0

  at Syncfusion.iOS.TreeView.TreeNodeContainer.OnMeasureTreeNodeContainer (System.Double width, System.Double height) [0x000ad] in <8b31fbf5b8524988a341a019ad70d9e6>:0

  at Syncfusion.iOS.TreeView.TreeNodeContainer.LayoutSubviews () [0x0002d] in <8b31fbf5b8524988a341a019ad70d9e6>:0

  at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain(int,string[],intptr,intptr)

  at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.10.0.21/src/Xamarin.iOS/UIKit/UIApplication.cs:86

  at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x0000e] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.10.0.21/src/Xamarin.iOS/UIKit/UIApplication.cs:65

  at TreeView.iOS.Application.Main (System.String[] args) [0x00001] in C:\Users\Gerold\source\repos\TreeView\TreeView.iOS\Main.cs:17