为类型为“ Xamarin.Forms.Xaml.ElementNode”的属性“ Parent”检测到自引用循环

Question

添加网格时出现Xaml错误。

{Newtonsoft.Json.JsonSerializationException: Self referencing loop detected for property 'Parent' with type 'Xamarin.Forms.Xaml.ElementNode'. 
Path 'exception.XmlInfo.Parent.Properties['Xamarin.Forms.Xaml.XmlName'].CollectionItems[0]'.