Listbox binding get selected item value - binding

Question

I'm new in Wpf and i face issue to get selected item in listbox
I created a simple xaml with a listbox and a textbox.
I use binding to populate my listbox including trigger (checked or not) that i want ot use later.
Xaml code:
<ListBox x:Name="LstB_Checklist" HorizontalAlignment="Left" Height="190" Margin="39,45,0,0" VerticalAlignment="Top" Width="275" Background="#FF363636" BorderBrush="{x:Null}" FontSize="18" Foreground="White" BorderThickness="2" SelectionChanged="LstB_Checklist_SelectionChanged" SelectedItem="{Binding SelectedProperty,Mode=TwoWay}" >
<ListBox.ItemContainerStyle>
<Style TargetType="ListBoxItem">
<Style.Triggers>
<Trigger Property="IsSelected" Value="True" >
<Setter Property="FontWeight" Value="Bold" />
<Setter Property="Background" Value="#FFFFDC00" />
<Setter Property="Foreground" Value="Black" />
</Trigger>
</Style.Triggers>
<Style.Resources>
<SolidColorBrush x:Key="{x:Static SystemColors.HighlightBrushKey}" Color="LightGray"/>
</Style.Resources>
</Style>
</ListBox.ItemContainerStyle>
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Image>
<Image.Style>
<Style TargetType="{x:Type Image}">
<Style.Triggers>
<DataTrigger Binding="{Binding Checked}" Value="false">
</DataTrigger>
<DataTrigger Binding="{Binding Checked}" Value="true">
</DataTrigger>
</Style.Triggers>
</Style>
</Image.Style>
</Image>
<TextBlock Text="{Binding Path=Title, Mode=TwoWay}" />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
<TextBox x:Name="txtb_Selection" HorizontalAlignment="Left" Height="23" Margin="60,264,0,0" TextWrapping="Wrap" Text="TextBox" VerticalAlignment="Top" Width="120"/>
in the code behind
public MainWindow()
{
InitializeComponent();
List<LstB_Item> items = new List<LstB_Item>();
items.Add(new LstB_Item() { Title = "Items 1", Checked = false });
items.Add(new LstB_Item() { Title = "Items 2", Checked = false });
items.Add(new LstB_Item() { Title = "Items 3", Checked = false });
LstB_Checklist.ItemsSource = items;
}
public class LstB_Item : INotifyPropertyChanged
{
public string Title { get; set; }
private bool _checked;
public bool Checked
{
get { return _checked; }
set { _checked = value; NotifyPropertyChanged(); }
}
public event PropertyChangedEventHandler PropertyChanged;
private void NotifyPropertyChanged([CallerMemberName] string propertyName = "")
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
private void LstB_Checklist_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
txtb_Selection.Text = LstB_Checklist.SelectedItem.ToString();
}
The lisbox is populated correctly. My question is: What is the right code to get the value selected item.
Many thanks for the support

Answer 1

I'm afraid the question was not so clear or the answer evident, but i post an answer, it could help:
Possible answer:
var selected = LstB_Checklist.SelectedItem as LstB_Item;
txtb_Selection.Text = selected.Title;