How to stop automatic refresh of a WPF ListBox Databinded on a EntityFramework object

I have a Xaml Page with a Databinded ListBox and a detail grid to create or update selected element.

My Page.DataContext is binded on a ADO.NET Entity Data Model table ("Univers").

    private void Page_Loaded(object sender, RoutedEventArgs e)
    {
        SEPDC = new开发者_如何学C Models.SEP();

        universViewSource = new CollectionViewSource();
        universViewSource.Source = SEPDC.Univers.Execute(System.Data.Objects.MergeOption.AppendOnly);

        DataContext = universViewSource;
    }

The Xaml code of the ListBox :

<ListBox DisplayMemberPath="Nom" ItemsSource="{Binding}" Name="universListBox" SelectedValuePath="IdUnivers"/>

When i select an element in the ListBox, the grid detail automatically display the information of the selected element

Here the "Nom" TextBox witch use TwoWay databinding :

<TextBox Name="nomTextBox" Text="{Binding Path=Nom, Mode=TwoWay}" />

When i modify the TextBox "Nom", the ListBox is automatically updated. Great ... But i haven't call the SaveChanges method of my SEPDC DataContext object ...

How can i stop the automatic refresh of my ListBox until i explicit call the SaveChanges method and if possible, without use the Binding UpdateSourceTrigger=Explicit option ?

Regards.

You can use two separate entity data context (SEPDC) objects. Your ListBox is bound to one and your detail grid to the other. When the SelectedValue changes in the ListBox, find the same entity in the detail grid's entity data context and set it. After saving changes from the detail grid's entity data context, refresh the one for the ListBox.

I use this technique but i have to recreate the ListBox SEPDC each time i refresh the ListBox.

        List<Models.Univers> list;

        using (Models.SEP dc = new Models.SEP())
            list = dc.Univers.Execute(System.Data.Objects.MergeOption.AppendOnly).ToList();

        universListBox.DataContext = list;

The Refresh method doesn't work.

Regards