Question

When changing the selected item in a ListBox, I’m getting a weird error where the changed item appears selected but I cannot deselect it or reselect it.

Is there a way to fix this?

Here’s a sample app that demonstrates the problem.

public partial class Window1 : Window
{
    public Window1()
    {
        InitializeComponent();
        this.DataContext = new WindowViewModel();
        lst.SelectedIndex = 0;
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        ((WindowViewModel)this.DataContext).Items[0] = "New Item";
    }
}

public class WindowViewModel
{
    public WindowViewModel()
    {
        Items = new ObservableCollection<string>();
        Items.Add("Item1");
        Items.Add("Item2");
        Items.Add("Item3");
    }

    public ObservableCollection<string> Items { get; set; }
}

<Window x:Class="WpfSelectionIssue.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1" Height="300" Width="300">
    <StackPanel>
        <Button Content="Change" Click="Button_Click" />
        <ListBox x:Name="lst" ItemsSource="{Binding Items}" />
    </StackPanel>
</Window>

ImageOfIssue http://img136.imageshack.us/img136/9396/wpfselectionissue.jpg

Answer 1

After searching a bit more I found the solution. Adding an IsSynchronizedWithCurrentItem to the ListBox solved the problem.

<ListBox 
    x:Name="lst" 
    ItemsSource="{Binding Items}" 
    IsSynchronizedWithCurrentItem="True"
    />