private void OnDrawBackgroundParameter(Rect rect, int index, bool selected, bool focused)
{
if (Event.current.type == EventType.Repaint)
{
GUIStyle style = ((index % 2) != 0) ? s_Styles.evenBackground : s_Styles.oddBackground;
((!selected && !focused) ? style : s_Styles.elementBackground).Draw(rect, false, selected, selected, focused);
}
}