Microsoft.Phone.Controls.ListPicker.OnManipulationStarted C# (CSharp) Method

        protected override void OnManipulationStarted(ManipulationStartedEventArgs e)
        {
            if (null == e)
            {
                throw new ArgumentNullException("e");
            }

            base.OnManipulationStarted(e);

            if (ListPickerMode == ListPickerMode.Normal)
            {
                if (!IsEnabled)
                {
                    e.Complete();
                    return;
                }

                Point p = e.ManipulationOrigin;

                if (e.OriginalSource != e.ManipulationContainer)
                {
                    p = e.ManipulationContainer.TransformToVisual((UIElement)e.OriginalSource).Transform(p);
                }

                if (IsValidManipulation(e.OriginalSource, p))
                {
                    IsHighlighted = true;
                }
            }
        }