Question

I have three different List collections.

How can I show them in one ListBox in three groups?

List<string> pending;
List<string> busy;
List<string> completed;

The end result should be something like this: vbcity.com/cfs-file.ashx/__key/…. But the only examples I find are working with one list.

Answer 1

Create a listbox with a Listview for the data template in your xaml code:

<Grid>
    <ListBox Height="100" HorizontalAlignment="Left" Margin="10,10,0,0" Name="lbxTasks"    VerticalAlignment="Top" Width="120">
        <ListBox.GroupStyle>
            <GroupStyle />
        </ListBox.GroupStyle>
        <ListBox.ItemTemplate>
            <DataTemplate>
                <ListView ItemsSource="{Binding Queue}" BorderThickness="0"/>
            </DataTemplate>
        </ListBox.ItemTemplate>
    </ListBox>
</Grid>

Then for your code behind, create and bind the lists. This is an example to test with:

namespace WpfApplication3
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        List<string> pending = new List<string> {"1","2"};
        List<string> busy = new List<string> { "4", "5" };
        List<string> completed = new List<string> { "7", "8" };

        private List<Tasks> MyTasks()
        {
            List<Tasks> tasks = new List<Tasks>();
            tasks.Add(new Tasks {Status = "Pending", Queue = pending});
            tasks.Add(new Tasks {Status = "Busy",Queue = busy});
            tasks.Add(new Tasks {Status = "Completed", Queue = completed});
            return tasks;
        }

        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            ICollectionView _tasksView = CollectionViewSource.GetDefaultView(MyTasks());
            _tasksView.GroupDescriptions.Add(new PropertyGroupDescription("Status"));
            lbxTasks.ItemsSource = _tasksView;
        }
    }

    public class Tasks
    {
        public List<string> Queue { get; set; }
        public string Status { get; set; }
    }
}

This creates a listbox for each Queue (or List) that you provide and groups it by the name of the List.

The output:

SOURCE: Modified the example from the link below into this format.
LISTBOX grouping using collectionView Source