WPF ListBox ItemsSource with DataTemplate

There are a couple of options.

One. make a custom control that is bound the data object for that row. On that custom control add the handler for the bound object.

I dont think your binding on the click will work. Sans the Binding Statment and just declare your click to a string.

Add the handler on the page where the control is housed. Keep in mind that if you bind this way you will only be able to work with the sender of that item (button) and it's properties. If you need to get at specific attributes on an object you maybe better off pursuing the first option.

Small Example demonstrating the functionality by adding 10 buttons to a list box with click events. HTH

DataTemplate XAML

<UserControl.Resources>
    <DataTemplate x:Name="MyDataTemplate">
        <Grid>
            <Button Click="Button_Click" Content="{Binding ItemText}"/>
        </Grid>
    </DataTemplate>
</UserControl.Resources>

ListBox XAML

<ListBox x:Name="ListBoxThingee" ItemTemplate="{StaticResource MyDataTemplate}"/>

Code Behind (I just plugged this all into the page.xaml file

public class MyClass
{
    public string ItemText { get; set; }
}


public partial class Page : UserControl
{
    ObservableCollection<MyClass> _Items;
    public Page()
    {
        InitializeComponent();

        _Items = new ObservableCollection<MyClass>();

        for (int i = 0; i < 10; i++)
        {
            _Items.Add(new MyClass() {ItemText= string.Format("Item - {0}", i)});
        }

        this.ListBoxThingee.ItemsSource = _Items;
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        Button _b = sender as Button;
        if (_b != null)
        {
            string _s = _b.Content as string;
            MessageBox.Show(_s);
        }

    }
}

What you wanted is to get the Expander control controls the ListBox Selection. You can easily archive this by setting a TwoWay Binding on the IsExpanded property of the Expander to the immediate ListBoxItem which you clicked.

 <Expander IsExpanded="{Binding IsSelected,Mode=TwoWay, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListBoxItem}}}">

UPDATE : If you need to avoid the automatic collapse when you select another item, make Listbox selection mode to multiple.

<ListBox SelectionMode="Multiple"