Listbox Not binding to a BindingList

Question

I have a ListBox on a form that is bound to a BindingList<T> in code behind but is not displaying the items within the BindingList<T>.

XAML:

<Window x:Class="MessageServer.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:MessageServer"
    Name="mainWindow" Title="Message Exchange Server" 
    Height="350" Width="525" Closing="Window_Closing">
<Grid>
    <Grid.ColumnDefinitions>
        <ColumnDefinition />
        <ColumnDefinition />
    </Grid.ColumnDefinitions>

    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition />
            <RowDefinition />
        </Grid.RowDefinitions>

        <ListBox Name="OutputList" Grid.Row="0" />
        <ListBox Name="Connected" Grid.Row="1" ItemsSource="{Binding ElementName=mainWindow, Path=ConnectedClients}">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <TextBlock Text="{Binding Path=FullIPAddress}" />
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>

    </Grid>
</Grid>

CodeBehind:

private BindingList<Client> _ConnectedClients;
public BindingList<Client> ConnectedClients
{
    get { return _ConnectedClients; }
    set { _ConnectedClients = value; }
}

public class Client : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    private TcpClient _tcpClient;
    public TcpClient tcpClient
    {
        get { return _tcpClient; }
        set
        {
            _tcpClient = value;
            NotifyPropertyChanged();
        }
    }

    public string FullIPAddress
    {
        get { return _tcpClient.Client.RemoteEndPoint.ToString(); }
    }

    public string IPAddress
    {
        get { return _tcpClient.Client.RemoteEndPoint.ToString().Split(':').ElementAt(0); }
    }

    public string PortNumber
    {
        get { return _tcpClient.Client.RemoteEndPoint.ToString().Split(':').ElementAt(1); }
    }

    public Client(TcpClient tcpClient)
    {
        this.tcpClient = tcpClient;
        NotifyPropertyChanged();
    }

    private void NotifyPropertyChanged()
    {
        NotifyPropertyChanged("tcpClient");
        NotifyPropertyChanged("FullIPAddress");
        NotifyPropertyChanged("IPAddress");
        NotifyPropertyChanged("PortNumber");
    }

    private void NotifyPropertyChanged(string propertyName)
    {
        if (PropertyChanged != null)
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
    }
}

Any Ideas why the list box is not displaying the items? Not sure if this is worth mentioning but When added items to the BindingList this is done on a seperate thread to the UI Thread. but I have tried using Dispatcher.BeginInvoke() but still does not work...

It sounds like you really want to use ObservableCollection. It sounds like BindingList should work, but on this SO post they seem say ObservableCollection is for WPF and BindingList for Winforms: http://stackoverflow.com/questions/4284663/difference-between-observablecollection-and-bindinglist — ShelbyZ, Nov 08 '11 at 17:12
I changed the BindingList to be of type ObservableCollection and this worked with no problems, the only change i had to make was when adding/removing items from the list i had to do it on the UI thread which is easily achieved (for those who do not know) using... Dispatcher.BeginInvoke(new Action(() => ConnectedClients.Add(client))); — Andy Clark, Nov 08 '11 at 17:29

score 3 · Answer 1 · edited May 23 '17 at 10:34

3

It sounds like you really want to use ObservableCollection. It sounds like BindingList should work, but on this SO post they seem say ObservableCollection is for WPF and BindingList for Winforms: Differences between BindingList and ObservableCollection

edited May 23 '17 at 10:34

Community

1
1

answered Nov 08 '11 at 17:39

ShelbyZ

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score 2 · Accepted Answer · answered Nov 08 '11 at 17:29

2

Try using an ObservableCollection<T>. It was designed specifically for WPF.

answered Nov 08 '11 at 17:29

Nick O

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Guess I should have read the comments on you question. @ShelbyZ you should have posted as answer instead of putting it in a comment. – Nick O Nov 08 '11 at 17:37
Mine was a guess on direction to go as I didn't have the time to work it out myself. – ShelbyZ Nov 08 '11 at 17:40

score 1 · Answer 3 · answered Nov 08 '11 at 17:13

1

You are trying to bind to Window.ConnectedClients, which is a property that doesn't exist.

You need to change your binding to DataContext.ConnectedClients to bind to Window.DataContext.ConnectedClients

ItemsSource="{Binding ElementName=mainWindow, Path=DataContext.ConnectedClients}"

answered Nov 08 '11 at 17:13

Rachel

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Alternatively, just bind to ConnectedClients, since it is apparently a property of the instance in the DataContext – flq Nov 08 '11 at 17:16
@Flq Yes that would work using the given code sample, but it wouldn't work if this is a simplified code sample and the ListBox DataContext is not the same as the Window DataContext – Rachel Nov 08 '11 at 17:26
@Rachel not sure what you mean when you say it is not a property that exists?? The list is a property of the Window class and does exist surely?? – Andy Clark Nov 08 '11 at 17:33
@MrsNezbit Sorry, thought you were using the MVVM design pattern. Since you're not using it and the collection is a property on your Window class, the binding is fine. – Rachel Nov 08 '11 at 18:19

Listbox Not binding to a BindingList

3 Answers3