Window.Close() from XAML

It’s been a long time since I last posted. Since then I have been working on my first WPF contract. I have definately drank the cool aid, I love WPF (when MVVM is being used anyway).

One thing I haven’t been able to find any info on is how to close a window from XAML. I tried and tried and then gave up. Until now!

Having discovered the power of Attached Behaviours, I decided to write one that would close a window. All you need do then is create a data trigger that watches a CloseSignal on the ViewModel and sets the Close property to true.

public static class WindowCloseBehaviour

{

public static void SetClose(DependencyObject target, bool value)

{

target.SetValue(CloseProperty, value);

}

public static readonly DependencyProperty CloseProperty =

DependencyProperty.RegisterAttached(

“Close”,

typeof(bool),

typeof(WindowCloseBehaviour),

new UIPropertyMetadata(false, OnClose));

private static void OnClose(DependencyObject sender, DependencyPropertyChangedEventArgs e)

{

if (e.NewValue is bool && ((bool)e.NewValue))

{

Window window = GetWindow(sender);

if (window != null)

window.Close();

}

}

private static Window GetWindow(DependencyObject sender)

{

Window window = null;

if (sender is Window)

window = (Window)sender;

if (window == null)

window = Window.GetWindow(sender);

return window;

}

}

and then in your XAML

<Style.Triggers>
<DataTrigger Binding=”{Binding CloseSignal}” Value=”true”>
<Setter Property=”Behaviours:WindowCloseBehaviour.Close” Value=”true” />
</DataTrigger>
</Style>