static void OverrideLookupChild(GLib.GType gtype, LookupChildNativeDelegate callback)
 {
     unsafe {
         IntPtr *raw_ptr = (IntPtr *)(((long)gtype.GetClassPtr()) + (long)class_abi.GetFieldOffset("lookup_child"));
         *raw_ptr = Marshal.GetFunctionPointerForDelegate((Delegate)callback);
     }
 }
        private bool InternalLookupChild(string prop_name, out Gst.Element element, out IntPtr pspec)
        {
            LookupChildNativeDelegate unmanaged = null;

            unsafe {
                IntPtr *raw_ptr = (IntPtr *)(((long)this.LookupGType().GetThresholdType().GetClassPtr()) + (long)class_abi.GetFieldOffset("lookup_child"));
                unmanaged = (LookupChildNativeDelegate)Marshal.GetDelegateForFunctionPointer(*raw_ptr, typeof(LookupChildNativeDelegate));
            }
            if (unmanaged == null)
            {
                throw new InvalidOperationException("No base method to invoke");
            }

            IntPtr native_prop_name = GLib.Marshaller.StringToPtrGStrdup(prop_name);
            IntPtr native_element;
            bool   __result = unmanaged(this.Handle, native_prop_name, out native_element, out pspec);

            GLib.Marshaller.Free(native_prop_name);
            element = GLib.Object.GetObject(native_element, true) as Gst.Element;
            return(__result);
        }