ChartDirector 7.0 (Java Edition)

X Zone Coloring




This example demonstrates using x zone colors - colors that change at certain x value thresholds.

In this example, a x zone colors are used as the color of the line, and as the fill color of the band surrounding the line.

The x zone color for the line is configured to change from solid blue color to a red dash line color upon reaching a certain x value threshold. The x zone color for the band is configured to change from semi-transparent blue to semi-transparent red upon reaching the same threshold.

X zone colors are created using Layer.xZoneColor. You can use a x zone color in any ChartDirector API that expects a color. For instance, you can use a x zone color as background color, fill color of data sets, line color, etc.

A single x zone color can support one threshold value and change between two colors. The two colors can be any colors, including another x zone color. You may create x zone colors with multiple thresholds by cascading multiple x zone colors this way.

Source Code Listing

[JSP Version] jspdemo/xzonecolor.jsp
<%@page import="ChartDirector.*, java.util.*" %> <% // The data for the chart double[] data = {50, 55, 47, 34, 42, 49, 63, 62, 73, 59, 56, 50, 64, 60, 67, 67, 58, 59, 73, 77, 84, 82, 80, 84, 89}; // The error data representing the error band around the data points double[] errData = {5, 6, 5.1, 6.5, 6.6, 8, 5.4, 5.1, 4.6, 5.0, 5.2, 6.0, 4.9, 5.6, 4.8, 6.2, 7.4, 7.1, 6.5, 9.6, 12.1, 15.3, 18.5, 20.9, 24.1}; // The timestamps for the data Date[] labels = {new GregorianCalendar(2001, 0, 1).getTime(), new GregorianCalendar(2001, 1, 1 ).getTime(), new GregorianCalendar(2001, 2, 1).getTime(), new GregorianCalendar(2001, 3, 1 ).getTime(), new GregorianCalendar(2001, 4, 1).getTime(), new GregorianCalendar(2001, 5, 1 ).getTime(), new GregorianCalendar(2001, 6, 1).getTime(), new GregorianCalendar(2001, 7, 1 ).getTime(), new GregorianCalendar(2001, 8, 1).getTime(), new GregorianCalendar(2001, 9, 1 ).getTime(), new GregorianCalendar(2001, 10, 1).getTime(), new GregorianCalendar(2001, 11, 1 ).getTime(), new GregorianCalendar(2002, 0, 1).getTime(), new GregorianCalendar(2002, 1, 1 ).getTime(), new GregorianCalendar(2002, 2, 1).getTime(), new GregorianCalendar(2002, 3, 1 ).getTime(), new GregorianCalendar(2002, 4, 1).getTime(), new GregorianCalendar(2002, 5, 1 ).getTime(), new GregorianCalendar(2002, 6, 1).getTime(), new GregorianCalendar(2002, 7, 1 ).getTime(), new GregorianCalendar(2002, 8, 1).getTime(), new GregorianCalendar(2002, 9, 1 ).getTime(), new GregorianCalendar(2002, 10, 1).getTime(), new GregorianCalendar(2002, 11, 1 ).getTime(), new GregorianCalendar(2003, 0, 1).getTime()}; // Create a XYChart object of size 550 x 220 pixels XYChart c = new XYChart(550, 220); // Set the plot area at (50, 10) and of size 480 x 180 pixels. Enabled both vertical and horizontal // grids by setting their colors to light grey (cccccc) c.setPlotArea(50, 10, 480, 180).setGridColor(0xcccccc, 0xcccccc); // Add a legend box (50, 10) (top of plot area) using horizontal layout. Use 8pt Arial font. Disable // bounding box (set border to transparent). LegendBox legendBox = c.addLegend(50, 10, false, "", 8); legendBox.setBackground(Chart.Transparent); // Add keys to the legend box to explain the color zones legendBox.addKey("Historical", 0x9999ff); legendBox.addKey("Forecast", 0xff9966); // Add a title to the y axis. c.yAxis().setTitle("Energy Consumption"); // Set the labels on the x axis c.xAxis().setLabels2(labels); // Set multi-style axis label formatting. Use Arial Bold font for yearly labels and display them as // "yyyy". Use default font for monthly labels and display them as "mmm". Replace some labels with // minor ticks to ensure the labels are at least 3 units apart. c.xAxis().setMultiFormat(Chart.StartOfYearFilter(), "<*font=Arial Bold*>{value|yyyy}", Chart.StartOfMonthFilter(), "{value|mmm}", 3); // Add a line layer to the chart LineLayer layer = c.addLineLayer2(); // Create the color to draw the data line. The line is blue (0x333399) to the left of x = 18, and // become a red (0xd04040) dash line to the right of x = 18. int lineColor = layer.xZoneColor(18, 0x333399, c.dashLineColor(0xd04040, Chart.DashLine)); // Add the data line layer.addDataSet(data, lineColor, "Average"); // We are not showing the data set name in the legend box. The name is for showing in tool tips // only. layer.setLegend(Chart.NoLegend); // Create the color to draw the err zone. The color is semi-transparent blue (0x809999ff) to the // left of x = 18, and become semi-transparent red (0x80ff9966) to the right of x = 18. int errColor = layer.xZoneColor(18, 0x809999ff, 0x80ff9966); // Add the upper border of the err zone layer.addDataSet(new ArrayMath(data).add(errData).result(), errColor, "Upper bound"); // Add the lower border of the err zone layer.addDataSet(new ArrayMath(data).sub(errData).result(), errColor, "Lower bound"); // Set the default line width to 2 pixels layer.setLineWidth(2); // In this example, we are not showing the data set name in the legend box layer.setLegend(Chart.NoLegend); // Color the region between the err zone lines c.addInterLineLayer(layer.getLine(1), layer.getLine(2), errColor); // Output the chart WebChartViewer viewer = new WebChartViewer(request, "chart1"); viewer.setChart(c, Chart.SVG); // Include tool tip for the chart. viewer.setImageMap(c.getHTMLImageMap("", "", "title='{dataSetName} on {xLabel|mmm yyyy}: {value} MJoule'")); %> <!DOCTYPE html> <html> <head> <title>X Zone Coloring</title> <!-- Include ChartDirector Javascript Library to support chart interactions --> <script type="text/javascript" src="cdjcv.js"></script> </head> <body style="margin:5px 0px 0px 5px"> <div style="font:bold 18pt verdana;"> X Zone Coloring </div> <hr style="border:solid 1px #000080; background:#000080" /> <div style="font:10pt verdana; margin-bottom:1.5em"> <a href="viewsource.jsp?file=<%=request.getServletPath()%>">View Source Code</a> </div> <!-- ****** Here is the chart image ****** --> <%= viewer.renderHTML(response) %> </body> </html>