using System;
using System.Windows;

namespace Microsoft.Windows.Shell
{
    public class ThumbButtonInfoCollection : FreezableCollection<ThumbButtonInfo>
    {
        protected override Freezable CreateInstanceCore()
        {
            return new ThumbButtonInfoCollection();
        }

        internal static ThumbButtonInfoCollection Empty
        {
            get
            {
                if (ThumbButtonInfoCollection.s_empty == null)
                {
                    ThumbButtonInfoCollection thumbButtonInfoCollection = new ThumbButtonInfoCollection();
                    thumbButtonInfoCollection.Freeze();
                    ThumbButtonInfoCollection.s_empty = thumbButtonInfoCollection;
                }
                return ThumbButtonInfoCollection.s_empty;
            }
        }

        private static ThumbButtonInfoCollection s_empty;
    }
}
