Question

I am doing something wrong .. you know how it is.

I have tried playing around with ItemsSource , DataContext , DisplayMemberPath and SelectedValuePath and I either get a blank list of a list of the ToString method being called in the Person object;

WHAT WOULD REALLY HELP is for someone to publish an answer that works for this example.

I have simplified the problem as I am having difficulty in general with databinding generics.

I have created a simple Generic List of Person and want to bind it to a combo. (also want to try use a ListView too).

I either get a list of blanks or a list of ‘xxxx.Person’ where xxxx = namespace

       <Window x:Class="BindingGenerics.MainWindow"
                xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                Title="MainWindow" Height="300" Width="300">
            <Grid>

                <ComboBox Name="ComboBox1"
                          ItemsSource="{Binding}"
                          Height="50"
                          DisplayMemberPath="Name"
                          SelectedValuePath="ID"
                          FontSize="14"
                          VerticalAlignment="Top">
                </ComboBox>

            </Grid>
        </Window>



using System.Windows;
using System.ComponentModel;

namespace BindingGenerics
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();

            Person p = new Person();
            // I have tried List and BindingList
            //List<Person> list = new List<Person>();
            BindingList<Person> list = new BindingList<Person>();

            p.Name = "aaaa";
            p.ID = "1111";
            list.Add(p);

            p = new Person();
            p.Name = "bbbb";
            p.ID = "2222";
            list.Add(p);

            p = new Person();
            p.Name = "cccc";
            p.ID = "3333";
            list.Add(p);

            p = new Person();
            p.Name = "dddd";
            p.ID = "4444";
            list.Add(p);

            ComboBox1.DataContext = list;
        }
    }

    public struct Person
    {
        public string Name;
        public string ID;
    }
}

Answer 1

In your code sample, Person.Name is a field rather than a property. WPF data binding considers only properties, not fields, so you need to change Person.Name to be a property.

Change your Person declaration to:

public class Person
{
  public string Name { get; set; }
  public string ID { get; set; }
}

(For production code, you’ll probably want to use an ObservableCollection<Person> rather than a List<Person> and either make Person immutable or make it implement INotifyPropertyChanged — but those aren’t the sources of your immediate problem.)