Microsoft.Phone.Controls.WrapPanel.MeasureOverride C# (CSharp) Method

        protected override Size MeasureOverride( Size constraint )
        {
            // Variables tracking the size of the current line, the total size
            // measured so far, and the maximum size available to fill.  Note
            // that the line might represent a row or a column depending on the
            // orientation.
            Orientation o = Orientation;
            OrientedSize lineSize = new OrientedSize( o );
            OrientedSize totalSize = new OrientedSize( o );
            OrientedSize maximumSize = new OrientedSize( o, constraint.Width, constraint.Height );

            // Determine the constraints for individual items
            double itemWidth = ItemWidth;
            double itemHeight = ItemHeight;
            bool hasFixedWidth = !double.IsNaN( itemWidth );
            bool hasFixedHeight = !double.IsNaN( itemHeight );
            Size itemSize = new Size(
                hasFixedWidth ? itemWidth : constraint.Width,
                hasFixedHeight ? itemHeight : constraint.Height );

            // Measure each of the Children
            foreach ( UIElement element in Children )
            {
                // Determine the size of the element
                element.Measure( itemSize );
                OrientedSize elementSize = new OrientedSize(
                    o,
                    hasFixedWidth ? itemWidth : element.DesiredSize.Width,
                    hasFixedHeight ? itemHeight : element.DesiredSize.Height );

                // If this element falls of the edge of the line
                if ( NumericExtensions.IsGreaterThan( lineSize.Direct + elementSize.Direct, maximumSize.Direct ) )
                {
                    // Update the total size with the direct and indirect growth
                    // for the current line
                    totalSize.Direct = Math.Max( lineSize.Direct, totalSize.Direct );
                    totalSize.Indirect += lineSize.Indirect;

                    // Move the element to a new line
                    lineSize = elementSize;

                    // If the current element is larger than the maximum size,
                    // place it on a line by itself
                    if ( NumericExtensions.IsGreaterThan( elementSize.Direct, maximumSize.Direct ) )
                    {
                        // Update the total size for the line occupied by this
                        // single element
                        totalSize.Direct = Math.Max( elementSize.Direct, totalSize.Direct );
                        totalSize.Indirect += elementSize.Indirect;

                        // Move to a new line
                        lineSize = new OrientedSize( o );
                    }
                }
                else
                {
                    // Otherwise just add the element to the end of the line
                    lineSize.Direct += elementSize.Direct;
                    lineSize.Indirect = Math.Max( lineSize.Indirect, elementSize.Indirect );
                }
            }

            // Update the total size with the elements on the last line
            totalSize.Direct = Math.Max( lineSize.Direct, totalSize.Direct );
            totalSize.Indirect += lineSize.Indirect;

            // Return the total size required as an un-oriented quantity
            return new Size( totalSize.Width, totalSize.Height );
        }