Wpf celleditingtemplate itemssource

Wpf celleditingtemplate itemssource I have two simple model classes and a ViewModel... Public Class GridItem { public stringName { get; set; } public int CompanyID { get; set; } public class CompanyItem { public class CompanyItem { public int ID { get; set; } public string Name { get; set; } public class ViewModel { public ViewModel() { GridItems = new ObservableCollection<GridItem> ... ................
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