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SfDropDownTree - Error if TItem class does not have bool Expanded property

Hi,

I have found what seems to be a very obscure bug with the DropDownTree component.  I think that the bug only came into existence with 25.1.37 as I'm pretty sure it worked Ok with 25.1.35.

The issue occurs if the TItem type does not have a bool Expanded property. (the error also occurs if a bool? property is provided).  This problem occurs even if the Expanded property is not assigned in <DropDownTreeField> property.

Following is a screenshot of the broken component and the resulting error.  Uncommenting the Expanded property will prevent the error occurring.

I have also attached the sample solution.

Empty


warn: Microsoft.AspNetCore.Components.Server.Circuits.RemoteRenderer[100]
      Unhandled exception rendering component: Object reference not set to an instance of an object.
      System.NullReferenceException: Object reference not set to an instance of an object.
         at Syncfusion.Blazor.Navigations.SfDropDownTree`2.UpdateState(String field, List`1 nodeList, String id, TItem itemData)
         at Syncfusion.Blazor.Navigations.SfDropDownTree`2.UpdateAllData(List`1 tempData, List`1 eNodes, List`1 cNodes, List`1 sNodes)
         at Syncfusion.Blazor.Navigations.SfDropDownTree`2.OnAfterRenderAsync(Boolean firstRender)
         at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle, ComponentState owningComponentState)
fail: Microsoft.AspNetCore.Components.Server.Circuits.CircuitHost[111]
      Unhandled exception in circuit 'nrso-i0XM4AyHGvfQl1QNcehq5_g6rjqK-96tmFqVRw'.
      System.NullReferenceException: Object reference not set to an instance of an object.
         at Syncfusion.Blazor.Navigations.SfDropDownTree`2.UpdateState(String field, List`1 nodeList, String id, TItem itemData)
         at Syncfusion.Blazor.Navigations.SfDropDownTree`2.UpdateAllData(List`1 tempData, List`1 eNodes, List`1 cNodes, List`1 sNodes)
         at Syncfusion.Blazor.Navigations.SfDropDownTree`2.OnAfterRenderAsync(Boolean firstRender)
         at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle, ComponentState owningComponentState)