Show how to implement a custom ComboBoxEdit with TreeView as a PopupContent and use it inside DXGrid as a custom column. We've modified this code example by using the DevExpress control version 13.1.

Gets or sets an object source used to generate the content of the TreeView. Equivalent **WinUI 2 API for UWP**: [Microsoft.UI.Xaml.Controls.TreeViewItem.ItemsSource ...