Walking the XAML VisualTree to find a parent of type

To find a parent item of type T, you can use the following helper class:

public static class DependencyObjectHelper
{
public static DependencyObject FindParent(this DependencyObject obj, Predicate where) {
var parent = VisualTreeHelper.GetParent(obj);

if (parent == null || where(parent)) {
return parent;
} else {
return parent.FindParent(where);
}
}

public static T FindParentOfType(this DependencyObject obj) where T : DependencyObject {
return (T)FindParent(obj, x => x is T);
}
}

This can then be utilised as follows:

Grid item = ((DependencyObject)childObject).FindParentOfType();

This was particularly useful when wanting to locate an invalid control from a ValidationSummary in silverlight, that was nested in an accordian panel:

BIG shout out goes to Jedi Master Twist for the lead on this 🙂