BrightIdeasSoftware.VirtualObjectListView.EnableVirtualGroups C# (CSharp) Метод

        protected void EnableVirtualGroups()
        {
            // We need to implement the IOwnerDataCallback interface
            if (this.ownerDataCallbackImpl == null)
                this.ownerDataCallbackImpl = new OwnerDataCallbackImpl(this);

            const int LVM_SETOWNERDATACALLBACK = 0x10BB;
            IntPtr ptr = Marshal.GetComInterfaceForObject(ownerDataCallbackImpl, typeof(IOwnerDataCallback));
            IntPtr x = NativeMethods.SendMessage(this.Handle, LVM_SETOWNERDATACALLBACK, ptr, 0);
            //System.Diagnostics.Debug.WriteLine(x);
            Marshal.Release(ptr);

            const int LVM_ENABLEGROUPVIEW = 0x1000 + 157;
            x = NativeMethods.SendMessage(this.Handle, LVM_ENABLEGROUPVIEW, 1, 0);
            //System.Diagnostics.Debug.WriteLine(x);
        }