ChartDirector 7.0 (Java Edition)

Finance Chart Track Line




This sample program demonstrates a track cursor for a finance chart programmed with the following features:

On the server side, the code draws the finance chart with the legend box set to transparent (so that the default legend box is not displayed), It outputs both the image and the Javascript Chart Model of the chart.

On the browser side, in the window onload event handler, Javascript is used to set up the event handler for the MouseMovePlotArea, TouchStartPlotArea, TouchMovePlotArea , ChartMove and Now events. The event handler calls trackFinance to draw the track cursor.

The trackFinance Javascript function is the routine that draws the track cursor. Its key elements are:

Source Code Listing

[JSP Version] jspdemo/trackfinance.jsp
<%@page import="ChartDirector.*, java.util.*" %> <% // Create a finance chart demo containing 100 days of data int noOfDays = 100; // To compute moving averages starting from the first day, we need to get extra data points before // the first day int extraDays = 30; // In this exammple, we use a random number generator utility to simulate the data. We set up the // random table to create 6 cols x (noOfDays + extraDays) rows, using 9 as the seed. RanTable rantable = new RanTable(9, 6, noOfDays + extraDays); // Set the 1st col to be the timeStamp, starting from Sep 4, 2011, with each row representing one // day, and counting week days only (jump over Sat and Sun) rantable.setDateCol(0, new GregorianCalendar(2011, 8, 4).getTime(), 86400, true); // Set the 2nd, 3rd, 4th and 5th columns to be high, low, open and close data. The open value starts // from 100, and the daily change is random from -5 to 5. rantable.setHLOCCols(1, 100, -5, 5); // Set the 6th column as the vol data from 5 to 25 million rantable.setCol(5, 50000000, 250000000); // Now we read the data from the table into arrays double[] timeStamps = rantable.getCol(0); double[] highData = rantable.getCol(1); double[] lowData = rantable.getCol(2); double[] openData = rantable.getCol(3); double[] closeData = rantable.getCol(4); double[] volData = rantable.getCol(5); // Create a FinanceChart object of width 720 pixels FinanceChart c = new FinanceChart(720); // Add a title to the chart c.addTitle("Finance Chart Demonstration"); // Disable default legend box, as we are using dynamic legend c.setLegendStyle("normal", 8, Chart.Transparent, Chart.Transparent); // Set the data into the finance chart object c.setData(timeStamps, highData, lowData, openData, closeData, volData, extraDays); // Add the main chart with 240 pixels in height c.addMainChart(240); // Add a 10 period simple moving average to the main chart, using brown color c.addSimpleMovingAvg(10, 0x663300); // Add a 20 period simple moving average to the main chart, using purple color c.addSimpleMovingAvg(20, 0x9900ff); // Add candlestick symbols to the main chart, using green/red for up/down days c.addCandleStick(0x00ff00, 0xff0000); // Add 20 days bollinger band to the main chart, using light blue (9999ff) as the border and // semi-transparent blue (c06666ff) as the fill color c.addBollingerBand(20, 2, 0x9999ff, 0xc06666ff); // Add a 75 pixels volume bars sub-chart to the bottom of the main chart, using green/red/grey for // up/down/flat days c.addVolBars(75, 0x99ff99, 0xff9999, 0x808080); // Append a 14-days RSI indicator chart (75 pixels high) after the main chart. The main RSI line is // purple (800080). Set threshold region to +/- 20 (that is, RSI = 50 +/- 25). The upper/lower // threshold regions will be filled with red (ff0000)/blue (0000ff). c.addRSI(75, 14, 0x800080, 20, 0xff0000, 0x0000ff); // Append a MACD(26, 12) indicator chart (75 pixels high) after the main chart, using 9 days for // computing divergence. c.addMACD(75, 26, 12, 9, 0x0000ff, 0xff00ff, 0x008000); // Create the WebChartViewer object WebChartViewer viewer = new WebChartViewer(request, "chart1"); // Output the chart viewer.setChart(c, Chart.SVG); // Output Javascript chart model to the browser to support tracking cursor viewer.setChartModel(c.getJsChartModel()); %> <!DOCTYPE html> <html> <head> <title>Finance Chart Track Line</title> <script type="text/javascript" src="cdjcv.js"></script> </head> <body style="margin:5px 0px 0px 5px"> <script type="text/javascript"> // // Use the window load event to set up the MouseMovePlotArea event handler // JsChartViewer.addEventListener(window, 'load', function() { var viewer = JsChartViewer.get('<%=viewer.getId()%>'); // Draw track cursor when mouse is moving over plotarea viewer.attachHandler(["MouseMovePlotArea", "TouchStartPlotArea", "TouchMovePlotArea", "ChartMove", "Now"], function(e) { this.preventDefault(e); // Prevent the browser from using touch events for other actions traceFinance(viewer, viewer.getPlotAreaMouseX()); }); }); // // Draw finance chart track line with legend // function traceFinance(viewer, mouseX) { // Remove all previously drawn tracking object viewer.hideObj("all"); // It is possible for a FinanceChart to be empty, so we need to check for it. if (!viewer.getChart()) return; // Get the data x-value that is nearest to the mouse var xValue = viewer.getChart().getNearestXValue(mouseX); // Iterate the XY charts (main price chart and indicator charts) in the FinanceChart var c = null; for (var i = 0; i < viewer.getChartCount(); ++i) { c = viewer.getChart(i); // Variables to hold the legend entries var ohlcLegend = ""; var legendEntries = []; // Iterate through all layers to build the legend array for (var j = 0; j < c.getLayerCount(); ++j) { var layer = c.getLayerByZ(j); var xIndex = layer.getXIndexOf(xValue); var dataSetCount = layer.getDataSetCount(); // In a FinanceChart, only layers showing OHLC data can have 4 data sets if (dataSetCount == 4) { var highValue = layer.getDataSet(0).getValue(xIndex); var lowValue = layer.getDataSet(1).getValue(xIndex); var openValue = layer.getDataSet(2).getValue(xIndex); var closeValue = layer.getDataSet(3).getValue(xIndex); if (closeValue == null) continue; // Build the OHLC legend ohlcLegend = "Open: " + openValue.toPrecision(4) + ", High: " + highValue.toPrecision(4) + ", Low: " + lowValue.toPrecision(4) + ", Close: " + closeValue.toPrecision(4); // We also draw an upward or downward triangle for up and down days and the % change var lastCloseValue = layer.getDataSet(3).getValue(xIndex - 1); if (lastCloseValue != null) { var change = closeValue - lastCloseValue; var percent = change * 100 / closeValue; if (change >= 0) ohlcLegend += "&nbsp;&nbsp;<span style='color:#008800;'>&#9650; "; else ohlcLegend += "&nbsp;&nbsp;<span style='color:#CC0000;'>&#9660; "; ohlcLegend += change.toPrecision(4) + " (" + percent.toFixed(2) + "%)</span>"; } // Add a spacer box, and make sure the line does not wrap within the legend entry ohlcLegend = "<nobr>" + ohlcLegend + viewer.htmlRect(20, 0) + "</nobr> "; } else { // Iterate through all the data sets in the layer for (var k = 0; k < dataSetCount; ++k) { var dataSet = layer.getDataSetByZ(k); var name = dataSet.getDataName(); var value = dataSet.getValue(xIndex); if ((!name) || (value == null)) continue; // In a FinanceChart, the data set name consists of the indicator name and its latest value. It is // like "Vol: 123M" or "RSI (14): 55.34". As we are generating the values dynamically, we need to // extract the indictor name out, and also the volume unit (if any). // The unit character, if any, is the last character and must not be a digit. var unitChar = name.charAt(name.length - 1); if ((unitChar >= '0') && (unitChar <= '9')) unitChar = ''; // The indicator name is the part of the name up to the colon character. var delimiterPosition = name.indexOf(':'); if (delimiterPosition != -1) name = name.substring(0, delimiterPosition); // In a FinanceChart, if there are two data sets, it must be representing a range. if (dataSetCount == 2) { // We show both values in the range var value2 = layer.getDataSetByZ(1 - k).getValue(xIndex); name = name + ": " + Math.min(value, value2).toPrecision(4) + " - " + Math.max(value, value2).toPrecision(4); } else { // In a FinanceChart, only the layer for volume bars has 3 data sets for up/down/flat days if (dataSetCount == 3) { // The actual volume is the sum of the 3 data sets. value = layer.getDataSet(0).getValue(xIndex) + layer.getDataSet(1).getValue(xIndex) + layer.getDataSet(2).getValue(xIndex); } // Create the legend entry name = name + ": " + value.toPrecision(4) + unitChar; } // Build the legend entry, consist of a colored square box and the name (with the data value in it). legendEntries.push("<nobr>" + viewer.htmlRect(5, 5, dataSet.getDataColor(), "solid 1px black") + " " + name + viewer.htmlRect(20, 0) + "</nobr>"); } } } // The legend is formed by concatenating the legend entries. var legend = legendEntries.reverse().join(" "); // Add the date and the ohlcLegend (if any) at the beginning of the legend legend = "<nobr>[" + c.xAxis().getFormattedLabel(xValue, "mmm dd, yyyy") + "]" + viewer.htmlRect(20, 0) + "</nobr> " + ohlcLegend + legend; // Get the plot area position relative to the entire FinanceChart var plotArea = c.getPlotArea(); var plotAreaLeftX = plotArea.getLeftX() + c.getAbsOffsetX(); var plotAreaTopY = plotArea.getTopY() + c.getAbsOffsetY(); // Draw a vertical track line at the x-position viewer.drawVLine("trackLine" + i, c.getXCoor(xValue) + c.getAbsOffsetX(), plotAreaTopY, plotAreaTopY + plotArea.getHeight(), "black 1px dotted"); // Display the legend on the top of the plot area viewer.showTextBox("legend" + i, plotAreaLeftX + 1, plotAreaTopY + 1, JsChartViewer.TopLeft, legend, "padding-left:5px;width:" + (plotArea.getWidth() - 1) + "px;font:11px Arial;-webkit-text-size-adjust:100%;"); } } </script> <div style="font-size:18pt; font-family:verdana; font-weight:bold"> Finance Chart Track Line </div> <hr style="border:solid 1px #000080" /> <div style="font-size:10pt; font-family: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>