WPF toolkit CheckListBox SelectedItemsOverride not working

Question

I have a check list box from the wpf toolkit 2. I cannot get all of the selected items. I read that I am supposed to use SelectedItemsOverride to get all of my selected items bu

Answer 1

I faced the same problem and solved it by assigning the private field of the property

In your example

private ObservableCollection<TestClass> _testClassSelected=new ObservableCollection<TestClass>();

Answer 2

I combined previous answers/comments and what worked for me was to bind SelectedItemsOverride to an ObservableCollection<T>, include UpdateSourceTrigger=PropertyChanged, and attach a method to the ObservableCollection<T>'s event CollectionChanged.

The XAML:

<xctk:CheckListBox 
    ItemsSource="{Binding AllItems}"
    DisplayMemberPath="Display"
    ValueMemberPath="Value" 
    SelectedItemsOverride="{Binding Path=DataContext.SelectedItems, RelativeSource={RelativeSource FindAncestor, AncestorType=Window}, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}">
</xctk:CheckListBox>

Code in ViewModel:

public IEnumerable<Item> AllItems { get; set; }

public ObservableCollection<Item> SelectedItems { get; set; }

public ViewModel()
{
    SelectedItems = new ObservableCollection<Item>();

    SelectedItems.CollectionChanged += SelectedItems_CollectionChanged;
}

private void SelectedItems_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
{
    // Handle collection changed event
}

Answer 3

try add Mode and UpdateSourceTrigger at binding

<xctk:CheckListBox Name="MyCheckList"
                   ItemsSource="{Binding TestClassCollection}"
                   DisplayMemberPath="DisplayName"
                   SelectedItemsOverride="{Binding TestClassSelected, 
                          Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />

update: I'd checked example code from closed issue at Extended WPF Toolkit CodePlex site. Try to change TestClassSelected property to ObservableCollection. (Still keep UpdateSourceTrigger described above in .xaml)

public ObservableCollection<TestClass> TestClassSelected