This is what I want:
- There is a combo-box column bound to the ApplicationKey property of ClassA
- The combo-box is populated with ApplicationTokens from a static function all.
- An ApplicationToken has a ApplicationName and ApplicationKey property
- When an item is selected in the drop-down, the ClassA.ApplicationKey property is set to the ApplicationToken.ApplicationKey on the selected item.
This is my current code, which populates the combobox but doesn't update ClassA.ApplicationKey.
<DataGridComboBoxColumn 
    Header="Application" 
    SelectedItemBinding="{Binding ApplicationKey, Converter={gui:DebugConverter}}" 
    SelectedValuePath="ApplicationKey" 
    DisplayMemberPath="ApplicationName" 
    ItemsSource="{Binding Source={x:Static app:ApplicationLookup.GetAllOrNone}}"/>
 
     
    