public T GetAttachedProperty <T>(AttachedProperty <T> prop)
{
Console.WriteLine("GET AttachedProperty");
return((T)(_AttachedProperties[prop] ?? prop.DefaultValue));
}
public void SetAttachedProperty <T>(AttachedProperty <T> prop, T val)
{
Console.WriteLine("SetAttachedProperty 1");
_AttachedProperties[prop] = val;
Console.WriteLine("SetAttachedProperty 2");
}