Bind to a value defined in the Settings

The solution above does work, but I find it quite verbose... you could use a custom markup extension instead, that could be used like this :

<ListBox x:Name="lb" ItemsSource="{my:SettingBinding Names}" />

Here is the code for this extension :

public class SettingBindingExtension : Binding
{
    public SettingBindingExtension()
    {
        Initialize();
    }

    public SettingBindingExtension(string path)
        :base(path)
    {
        Initialize();
    }

    private void Initialize()
    {
        this.Source = WpfApplication1.Properties.Settings.Default;
        this.Mode = BindingMode.TwoWay;
    }
}

More details here : http://www.thomaslevesque.com/2008/11/18/wpf-binding-to-application-settings-using-a-markup-extension/

First, you need to add a custom XML namespace that will design the namespace where the settings are defined:

xmlns:properties="clr-namespace:TestSettings.Properties"

Then, in your XAML file, access the default settings instance using the following syntax:

{x:Static properties:Settings.Default}

So here is the final result code:

<ListBox x:Name="lb"
         ItemsSource="{Binding Source={x:Static properties:Settings.Default},
                               Path=Names}" />

Source: WPF - How to bind a control to a property defined in the Settings?

---

Note: As pointed out by @Daniel and @nabulke, don't forget to set Access Modifier of your settings file to Public and Scope to User