c# - ComboBox SelectedItem binding does not work for an object in a collection

Question

I have the following XAML:

<Grid x:Name="main_grid">
    <ItemsControl ItemsSource="{Binding MyThings}">
        <ItemsControl.ItemTemplate>
            <DataTemplate>
                <ComboBox ItemsSource="{Binding DataContext.Things, ElementName=main_grid}" SelectedItem="{Binding .}" />
            </DataTemplate>
        </ItemsControl.ItemTemplate>
    </ItemsControl>
</Grid>

MyThings and Things are both ObservableCollection<Thing>.

If Things contains three objects, and I have added one of them to MyThings, when the view/XAML loads the ComboBox will initially display that item. However, when I change the selection in the ComboBox, the item within MyThings is not replace with the newly selected item as I would expect (if it were bound to a single object, rather than an object in a collection, it would be replaced).

Why does this not work? And is there a way to make it work?

question from:https://stackoverflow.com/questions/65852798/combobox-selecteditem-binding-does-not-work-for-an-object-in-a-collection

Answer 1

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