/// <summary>    /// TilePanel    /// 瀑布流布局    /// </summary>    public class TilePanel : Panel    {        #region 枚举        private enum OccupyType        {            NONE,            WIDTHHEIGHT,            OVERFLOW        }        #endregion        #region 属性        /// <summary>        /// 容器内元素的高度        /// </summary>        public int TileHeight        {            get { return (int)GetValue(TileHeightProperty); }            set { SetValue(TileHeightProperty, value); }        }        /// <summary>        /// 容器内元素的高度        /// </summary>        public static readonly DependencyProperty TileHeightProperty =            DependencyProperty.Register("TileHeight", typeof(int), typeof(TilePanel), new FrameworkPropertyMetadata(100, FrameworkPropertyMetadataOptions.AffectsMeasure));        /// <summary>        /// 容器内元素的宽度        /// </summary>        public int TileWidth        {            get { return (int)GetValue(TileWidthProperty); }            set { SetValue(TileWidthProperty, value); }        }        /// <summary>        /// 容器内元素的宽度        /// </summary>        public static readonly DependencyProperty TileWidthProperty =            DependencyProperty.Register("TileWidth", typeof(int), typeof(TilePanel), new FrameworkPropertyMetadata(100, FrameworkPropertyMetadataOptions.AffectsMeasure));        /// <summary>        ///        /// </summary>        /// <param name="obj"></param>        /// <returns></returns>        public static int GetWidthPix(DependencyObject obj)        {            return (int)obj.GetValue(WidthPixProperty);        }        /// <summary>        ///        /// </summary>        /// <param name="obj"></param>        /// <param name="value"></param>        public static void SetWidthPix(DependencyObject obj, int value)        {            if (value > 0)            {                obj.SetValue(WidthPixProperty, value);            }        }        /// <summary>        /// 元素的宽度比例，相对于TileWidth        /// </summary>        public static readonly DependencyProperty WidthPixProperty =            DependencyProperty.RegisterAttached("WidthPix", typeof(int), typeof(TilePanel), new FrameworkPropertyMetadata(1, FrameworkPropertyMetadataOptions.AffectsParentMeasure));        /// <summary>        ///        /// </summary>        /// <param name="obj"></param>        /// <returns></returns>        public static int GetHeightPix(DependencyObject obj)        {            return (int)obj.GetValue(HeightPixProperty);        }        /// <summary>        ///        /// </summary>        /// <param name="obj"></param>        /// <param name="value"></param>        public static void SetHeightPix(DependencyObject obj, int value)        {            if (value > 0 )            {                obj.SetValue(HeightPixProperty, value);            }        }        /// <summary>        /// 元素的高度比例，相对于TileHeight        /// </summary>        public static readonly DependencyProperty HeightPixProperty =            DependencyProperty.RegisterAttached("HeightPix", typeof(int), typeof(TilePanel), new FrameworkPropertyMetadata(1, FrameworkPropertyMetadataOptions.AffectsParentMeasure));        /// <summary>        /// 排列方向        /// </summary>        public Orientation Orientation        {            get { return (Orientation)GetValue(OrientationProperty); }            set { SetValue(OrientationProperty, value); }        }        /// <summary>        /// 排列方向        /// </summary>        public static readonly DependencyProperty OrientationProperty =            DependencyProperty.Register("Orientation", typeof(Orientation), typeof(TilePanel), new FrameworkPropertyMetadata(Orientation.Horizontal, FrameworkPropertyMetadataOptions.AffectsMeasure));        /// <summary>        /// 格子数量        /// </summary>        public int TileCount        {            get { return (int)GetValue(TileCountProperty); }            set { SetValue(TileCountProperty, value); }        }        /// <summary>        /// 格子数量        /// </summary>        public static readonly DependencyProperty TileCountProperty =            DependencyProperty.Register("TileCount", typeof(int), typeof(TilePanel), new PropertyMetadata(4));        /// <summary>        /// Tile之间的间距        /// </summary>        public Thickness TileMargin        {            get { return (Thickness)GetValue(TileMarginProperty); }            set { SetValue(TileMarginProperty, value); }        }        /// <summary>        /// Tile之间的间距        /// </summary>        public static readonly DependencyProperty TileMarginProperty =            DependencyProperty.Register("TileMargin", typeof(Thickness), typeof(TilePanel), new FrameworkPropertyMetadata(new Thickness(2), FrameworkPropertyMetadataOptions.AffectsMeasure));        /// <summary>        /// 最小的高度比例        /// </summary>        private int MinHeightPix { get; set; }        /// <summary>        /// 最小的宽度比例        /// </summary>        private int MinWidthPix { get; set; }        #endregion        #region 方法        private Dictionary<string, bool> Maps { get; set; }        private OccupyType SetMaps(Point currentPosition, Size childPix)        {            var isOccupy = OccupyType.NONE;            if (currentPosition.X + currentPosition.Y != 0)            {                if (this.Orientation == System.Windows.Controls.Orientation.Horizontal)                {                    isOccupy = this.IsOccupyWidth(currentPosition, childPix);                }                else                {                    isOccupy = this.IsOccupyHeight(currentPosition, childPix);                }            }            if (isOccupy == OccupyType.NONE)            {                for (int i = 0; i < childPix.Width; i++)                {                    for (int j = 0; j < childPix.Height; j++)                    {                        this.Maps[string.Format("x_{0}y_{1}", currentPosition.X + i, currentPosition.Y + j)] = true;                    }                }            }            return isOccupy;        }        private OccupyType IsOccupyWidth(Point currentPosition, Size childPix)        {            //计算当前行能否放下当前元素            if (this.TileCount - currentPosition.X - childPix.Width < 0)            {                return OccupyType.OVERFLOW;            }            for (int i = 0; i < childPix.Width; i++)            {                if (this.Maps.ContainsKey(string.Format("x_{0}y_{1}", currentPosition.X + i, currentPosition.Y)))                {                    return OccupyType.WIDTHHEIGHT;                }            }            return OccupyType.NONE;        }        private OccupyType IsOccupyHeight(Point currentPosition, Size childPix)        {            //计算当前行能否放下当前元素            if (this.TileCount - currentPosition.Y - childPix.Height < 0)            {                return OccupyType.OVERFLOW;            }            for (int i = 0; i < childPix.Height; i++)            {                if (this.Maps.ContainsKey(string.Format("x_{0}y_{1}", currentPosition.X, currentPosition.Y + i)))                {                    return OccupyType.WIDTHHEIGHT;                }            }            return OccupyType.NONE;        }        /// <summary>        ///        /// </summary>        /// <param name="finalSize"></param>        /// <returns></returns>        protected override Size ArrangeOverride(Size finalSize)        {            Size childPix = new Size();            Point childPosition = new Point();            Point? lastChildPosition = null;            OccupyType isOccupy = OccupyType.NONE;            FrameworkElement child;            this.Maps = new Dictionary<string, bool>();            for (int i = 0; i < this.Children.Count; )            {                child = this.Children[i] as FrameworkElement;                childPix.Width = TilePanel.GetWidthPix(child);                childPix.Height = TilePanel.GetHeightPix(child);                                if (this.Orientation == System.Windows.Controls.Orientation.Vertical)                {                    if (childPix.Height > this.TileCount)                    {                        childPix.Height = this.TileCount;                    }                }                else                {                    if (childPix.Width > this.TileCount)                    {                        childPix.Width = this.TileCount;                    }                }                isOccupy = this.SetMaps(childPosition, childPix);                //换列                if (isOccupy == OccupyType.WIDTHHEIGHT)                {                    if (lastChildPosition == null) lastChildPosition = childPosition;                    if (this.Orientation == System.Windows.Controls.Orientation.Horizontal)                    {                        childPosition.X += this.MinWidthPix;                    }                    else                    {                        childPosition.Y += this.MinHeightPix;                    }                }                //换行                else if (isOccupy == OccupyType.OVERFLOW)                {                    if (lastChildPosition == null) lastChildPosition = childPosition;                    if (this.Orientation == System.Windows.Controls.Orientation.Horizontal)                    {                        childPosition.X = 0;                        childPosition.Y += this.MinHeightPix;                    }                    else                    {                        childPosition.Y = 0;                        childPosition.X += this.MinWidthPix;                    }                }                else                {                    i++;                    child.Arrange(new Rect(childPosition.X * this.TileWidth + childPosition.X / this.MinWidthPix * (this.TileMargin.Left + this.TileMargin.Right),                                           childPosition.Y * this.TileHeight + childPosition.Y / this.MinHeightPix * (this.TileMargin.Top + this.TileMargin.Bottom),                                           child.DesiredSize.Width, child.DesiredSize.Height));                    if (lastChildPosition != null)                    {                        childPosition = (Point)lastChildPosition;                        lastChildPosition = null;                    }                    else                    {                        if (this.Orientation == System.Windows.Controls.Orientation.Horizontal)                        {                            childPosition.X += childPix.Width;                        }                        else                        {                            childPosition.Y += childPix.Height;                        }                    }                }            }            return finalSize;        }        /// <summary>        ///        /// </summary>        /// <param name="constraint"></param>        /// <returns></returns>        protected override Size MeasureOverride(Size constraint)        {            int childWidthPix, childHeightPix, maxRowCount = 0;            if (this.Children.Count == 0) return new Size();            //遍历孩子元素            foreach (FrameworkElement child in this.Children)            {                childWidthPix = TilePanel.GetWidthPix(child);                childHeightPix = TilePanel.GetHeightPix(child);                if (this.MinHeightPix == 0) this.MinHeightPix = childHeightPix;                if (this.MinWidthPix == 0) this.MinWidthPix = childWidthPix;                if (this.MinHeightPix > childHeightPix) this.MinHeightPix = childHeightPix;                if (this.MinWidthPix > childWidthPix) this.MinWidthPix = childWidthPix;            }            foreach (FrameworkElement child in this.Children)            {                childWidthPix = TilePanel.GetWidthPix(child);                childHeightPix = TilePanel.GetHeightPix(child);                child.Margin = this.TileMargin;                child.HorizontalAlignment = System.Windows.HorizontalAlignment.Left;                child.VerticalAlignment = System.Windows.VerticalAlignment.Top;                child.Width = this.TileWidth * childWidthPix + (child.Margin.Left + child.Margin.Right) * ((childWidthPix - this.MinWidthPix) / this.MinWidthPix);                child.Height = this.TileHeight * childHeightPix + (child.Margin.Top + child.Margin.Bottom) * ((childHeightPix - this.MinHeightPix) / this.MinHeightPix);                maxRowCount += childWidthPix * childHeightPix;                child.Measure(new Size(double.PositiveInfinity, double.PositiveInfinity));            }            if (this.TileCount <= 0) throw new ArgumentOutOfRangeException();            //if (this.MinWidthPix == 0) this.MinWidthPix = 1;            //if (this.MinHeightPix == 0) this.MinHeightPix = 1;            if (this.Orientation == Orientation.Horizontal)            {                this.Width = constraint.Width = this.TileCount * this.TileWidth + this.TileCount / this.MinWidthPix * (this.TileMargin.Left + this.TileMargin.Right);                double heightPix = Math.Ceiling((double)maxRowCount / this.TileCount);                if (!double.IsNaN(heightPix))                    constraint.Height = heightPix * this.TileHeight + heightPix / this.MinHeightPix * (this.TileMargin.Top + this.TileMargin.Bottom);            }            else            {                this.Height = constraint.Height = this.TileCount * this.TileHeight + this.TileCount / this.MinHeightPix * (this.TileMargin.Top + this.TileMargin.Bottom);                double widthPix = Math.Ceiling((double)maxRowCount / this.TileCount);                if (!double.IsNaN(widthPix))                    constraint.Width = widthPix * this.TileWidth + widthPix / this.MinWidthPix * (this.TileMargin.Left + this.TileMargin.Right);            }            return constraint;        }        #endregion    }