Question

Some of the items in my ListBox use a template that contains a button and a TextBox. How can I make it such that it is impossible to select these items from the list, but still possible to interract with the button?

EDIT:

I still need to be able to select other items in this list, just not ones with this template.

Answer 1

We can use a attached property to the ListBoxItem (after I implemented I found someone who had done almost the same) :

public class ListBoxItemEx
{
    public static bool GetCanSelect(DependencyObject obj)
    {
        return (bool)obj.GetValue(CanSelectProperty);
    }
    public static void SetCanSelect(DependencyObject obj, bool value)
    {
        obj.SetValue(CanSelectProperty, value);
    }
    public static readonly DependencyProperty CanSelectProperty =
        DependencyProperty.RegisterAttached("CanSelect", typeof(bool), typeof(ListBoxItemEx), new UIPropertyMetadata(true, OnCanSelectChanged));

    private static void OnCanSelectChanged(DependencyObject sender, DependencyPropertyChangedEventArgs args)
    {
        var item = sender as ListBoxItem;
        if (item == null)
            return;

        if ((bool)args.NewValue)
        {
            item.Selected -= ListBoxItemSelected;
        }
        else
        {
            item.Selected += ListBoxItemSelected;
            item.IsSelected = false;
        }
    }

    private static void ListBoxItemSelected(object sender, RoutedEventArgs e)
    {
        var item = sender as ListBoxItem;
        if (item == null)
            return;
        item.IsSelected = false;
    }
}

The xaml:

<Window x:Class="WpfApplication1.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
    xmlns:local="clr-namespace:WpfApplication1"
    Title="MainWindow"
    Width="525"
    Height="350">
<Window.Resources>
    <Style x:Key="ListBoxItemStyle" TargetType="{x:Type ListBoxItem}">
        <Setter Property="local:ListBoxItemEx.CanSelect" Value="{Binding CanSelect}"/>
    </Style>
</Window.Resources>     
<Window.DataContext>
    <local:ViewModel />
</Window.DataContext>
<Grid Name="LayoutRoot">
    <ListBox ItemsSource="{Binding Elements}" ItemContainerStyle="{DynamicResource ListBoxItemStyle}" SelectionMode="Multiple" />
</Grid>

The viewmodel:

public class ViewModel : INotifyPropertyChanged
{
    #region INotifyPropertyChanged values

    public event PropertyChangedEventHandler PropertyChanged;

    protected void OnPropertyChanged(string propertyName)
    {
        if (this.PropertyChanged != null)
        {
            this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }
    #endregion


    public List<Dummy> Elements { get; set; }

    public ViewModel()
    {
        this.Elements = new List<Dummy>(){
            new Dummy() { CanSelect =true, MyProperty = "Element1"},
            new Dummy() { CanSelect =false, MyProperty = "Element2"},
            new Dummy() { CanSelect =true, MyProperty = "Element3"},
            new Dummy() { CanSelect =false, MyProperty = "Element4"},
            new Dummy() { CanSelect =true, MyProperty = "Element5"},
            new Dummy() { CanSelect =true, MyProperty = "Element6"},
            new Dummy() { CanSelect =true, MyProperty = "Element7"},
            new Dummy() { CanSelect =true, MyProperty = "Element8"},
            new Dummy() { CanSelect =false, MyProperty = "Element9"},
        };
    }
}

public class Dummy
{
    public bool CanSelect { get; set; }

    public string MyProperty { get; set; }

    public override string ToString()
    {
        return this.MyProperty;
    }
}

The only caveat with this approach is that trying to select an unselectable item unselects the current selected one if the ListBox has single selection, or unselects all, if the ListBox has extended selection.