User Interface Patterns

using System.Collections;
using System.Collections.Generic;


namespace ActiveMVC
{

    public class SimplePieChartData : IEnumerable<double>
    {

        private readonly List<double> _items;


        public SimplePieChartData()
        {
            _items = new List<double>();
            Total = 0;
        }


        public void Remove(double value)
        {
            _items.Remove(value);
            Total -= value;
        }


        public void Clear()
        {
            Total = 0;
            _items.Clear();
        }


        public void Add(double value)
        {
            _items.Add(value);
            Total += value;
        }


        internal void Add(double value, bool isActive)
        {
            if (isActive) ActiveItemIndex = Count;
            Add(value);
        }


        public double this[int index]
        {
            get { return _items[index]; }
        }


        IEnumerator<double> IEnumerable<double>.GetEnumerator()
        {
            return _items.GetEnumerator();
        }


        IEnumerator IEnumerable.GetEnumerator()
        {
            return _items.GetEnumerator();
        }


        public double Total { get; private set; }
        public int Count { get { return _items.Count; } }
        public int ActiveItemIndex { get; private set; }
    }
}