wpf combobox with checkbox - selecteditem

Question

I have a simple ComboBox with CheckBoxes as Items. How can I prevent the actual selection of the items. The user should only be able to check or uncheck the checkboxes?

Answer 1

Ok, I already tried before to use GetBindingExpression(...).UpdateTarget() because my TextProperty is bound but nothing happend. This function will only have an effect after the layout was updated. So the result:

/// <summary>
/// Prevents the selection of an item and displays the result of the TextProperty-Binding
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void SeveritiesComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    ComboBox box = sender as ComboBox;

    if (box == null)
        return;

    if (box.SelectedItem != null)
    {
        box.SelectedItem = null;

        EventHandler layoutUpdated = null;

        layoutUpdated = new EventHandler((o, ev) =>
        {
            box.GetBindingExpression(ComboBox.TextProperty).UpdateTarget();
            box.LayoutUpdated -= layoutUpdated;
        });

        box.LayoutUpdated += layoutUpdated;
    }
}

Answer 2

What about if you change your ComboBox to ItemsControl:

<ItemsControl ItemsSource="{Binding Path= Items}">
  <ItemsControl.ItemTemplate>  
    <DataTemplate>  
      <CheckBox IsChecked="{Binding Checked}" Content="{Binding Name}" />
    </DataTemplate>
  </ItemsControl.ItemTemplate>
</ItemsControl> 

Having an ItemsControl instead of a ComboBox will display all the items only checkable.