Beispiel #1
0
        /// <summary>
        /// Layout all legned items.
        /// </summary>
        public virtual void MeasureSize(DrawingContext dc, Rectangle parentClientRect)
        {
            var ds = Chart.DataSource;

            if (ds == null)
            {
                return;
            }

            int count = SymbolCount;

            Children.Clear();

            RGFloat maxSymbolWidth = 0, maxSymbolHeight = 0, maxLabelWidth = 0, maxLabelHeight = 0;

            // Suppress the legend when it has no labels or just repeats the chart title
            if (count == 1 && string.IsNullOrEmpty(Chart.Title) && GetSymbolText(0) == Chart.GetDisplayTitle())
            {
                return;
            }

            #region Measure Sizes
            for (int index = 0; index < count; index++)
            {
                string label = GetSymbolText(index);

                if (string.IsNullOrEmpty(label))
                {
                    continue;
                }

                var symbolSize = GetSymbolSize(index);

                if (maxSymbolWidth < symbolSize.Width)
                {
                    maxSymbolWidth = symbolSize.Width;
                }
                if (maxSymbolHeight < symbolSize.Height)
                {
                    maxSymbolHeight = symbolSize.Height;
                }

                var legendItem = new ChartLegendItem(Chart.DataSerialStyles[index], label)
                {
                    FontName     = FontName,
                    FontSize     = FontSize,
                    FontStyles   = FontStyles,
                    SymbolBounds = new Rectangle(new Point(0, 0), symbolSize),
                };

                var labelSize = PlatformUtility.MeasureText(dc, label, legendItem.FontName, legendItem.FontSize, legendItem.FontStyles);

                if (maxLabelWidth < labelSize.Width)
                {
                    maxLabelWidth = labelSize.Width;
                }
                if (maxLabelHeight < labelSize.Height)
                {
                    maxLabelHeight = labelSize.Height;
                }

                legendItem.LabelBounds = new Rectangle(new Point(0, 0), labelSize);

                Children.Add(legendItem);
            }
            #endregion             // Measure Sizes

            #region Layout
            const RGFloat symbolLabelSpacing = 4;

            var itemWidth  = maxSymbolWidth + symbolLabelSpacing + maxLabelWidth;
            var itemHeight = Math.Max(maxSymbolHeight, maxLabelHeight);

            var     clientRect = parentClientRect;
            RGFloat x = 0, y = 0, right = 0, bottom = 0, overflow = 0;

            if (LegendPosition == LegendPosition.Top || LegendPosition == LegendPosition.Bottom)
            {
                overflow = clientRect.Width - itemWidth;
            }

            foreach (var item in Children)
            {
                if (item is ChartLegendItem legendItem)
                {
                    legendItem.SetSymbolLocation(0, (itemHeight - legendItem.SymbolBounds.Height) / 2);
                    legendItem.SetLabelLocation(maxSymbolWidth + symbolLabelSpacing, (itemHeight - legendItem.LabelBounds.Height) / 2);

                    legendItem.Bounds = new Rectangle(x, y, itemWidth, itemHeight);

                    if (right < legendItem.Right)
                    {
                        right = legendItem.Right;
                    }
                    if (bottom < legendItem.Bottom)
                    {
                        bottom = legendItem.Bottom;
                    }
                }

                const RGFloat itemSpacing = 10;

                x += itemWidth + itemSpacing;

                if (x > overflow)
                {
                    x  = 0;
                    y += itemHeight + itemSpacing;
                }
            }
            #endregion             // Layout

            layoutedSize = new Size(right + 10, bottom);
        }