private static void OnStateChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
        {
            InclusionExclusionCheckBox fourStateCheckBox = o as InclusionExclusionCheckBox;

            if (fourStateCheckBox != null)
            {
                fourStateCheckBox.OnStateChanged((InclusionExclusionCheckBoxState)e.OldValue, (InclusionExclusionCheckBoxState)e.NewValue);
            }
        }
        private static void OnHasPartialInclusionChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
        {
            InclusionExclusionCheckBox inclusionExclusionCheckBox = o as InclusionExclusionCheckBox;

            if (inclusionExclusionCheckBox != null)
            {
                inclusionExclusionCheckBox.OnHasPartialInclusionChanged((bool)e.OldValue, (bool)e.NewValue);
            }
        }