Question

I am very new to WPF, and help appreciated:

Model:
   Collection<Presenter>,
   Presenter has a Collection<Presentation>,
   Presentation has a TeachingSession property (which contains a DateTime? property)

I am trying to have a treeview display:

presenter name
   [combobox of available Dates]

At the moment, each presenter name in the treeview is displaying correctly, and the first parent item expanded displays the combobox with the correctly selected date. However, comboboxes displaying at any one time are all ‘in sync’ – that is changing the value in a combobox (or expanding a different treeview item) changes the value for all comboboxes which can be seen, so they all display the same date.

<TreeView Name="PresenterTreeView" ItemsSource="{Binding}">
    <TreeView.Resources>
        <HierarchicalDataTemplate DataType="{x:Type local:Presenter}"
                  ItemsSource="{Binding Path=Presentations}">
            <TextBlock Text="{Binding Path=FullName}" />
        </HierarchicalDataTemplate>
        <HierarchicalDataTemplate DataType="{x:Type local:Presentation}">
            <ComboBox SelectedItem="{Binding Path=TeachingSession, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                      DisplayMemberPath="SessionDate"
                      ItemsSource="{Binding Source={StaticResource availableDatesViewSource}}" >
            </ComboBox>
        </HierarchicalDataTemplate>
    </TreeView.Resources>
</TreeView>

Answer 1

Because of sa_ddam213’s answer, i was able to track the problem down to the default synchronisation with the CollectionViewSource used to bindItemsSource

The combobox needed the attribute:

IsSynchronizedWithCurrentItem="False"