WPF user control : list box item not shown in WPF application

Question

I want to make a wpf user control with list box. in this list box i add a stackpanel as a listbox item.But when i want to use my user control in a application,this user control not showing any data .

here my xaml code of user control

     <Grid>
    <ListBox x:Name="lb" >
        <ListBox.ItemContainerStyle>
            <Style TargetType="{x:Type ListBoxItem}">
                <Setter Property="Template">
                    <Setter.Value>
                        <ControlTemplate TargetType="{x:Type ListBoxItem}">
                            <ContentPresenter/>
                        </ControlTemplate>
                    </Setter.Value>
                </Setter>
            </Style>
        </ListBox.ItemContainerStyle>
    </ListBox>
</Grid>

i add data in list box like this

 StackPanel sp1 = new StackPanel();
 sp1.Children.Add(someuielement);// some ui element i generate dynamically 
 lb.Items.Add(sp1);

my problem is how to show data in main application. i am not using any binding and not able to figure out how to do this.

thanks

Answer 1

The recommended way is to use a view model and bind it to the Items property of the ListBox. Like this:

<ListBox ItemsSource="{Binding DataItems}">...

Then in the codebehind instead of dynamically generating the ui elements you would simply bind your view models to the control, or the parent window.

lb.DataContext = new MyViewModel();

which may look like this:

class MyViewModel : ObservableObject
{
    public ObservableCollection<MyDataItem> DataItems {get; private set;}
    public MyViewModel()
    {
        this.DataItems = new ObservableCollection<MyDataItem>();
    }
}

See here for a simple ObservableObject implementation: http://justinmchase.com/2010/08/26/observableobject-for-wpf-mvvm/