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/ChartDirector/Tracking Cursor/Track Line with Data Labels
Required plugins for this example: MBS ChartDirector Plugin
You find this example project in your Plugins Download as a Xojo project file within the examples folder: /ChartDirector/Tracking Cursor/Track Line with Data Labels
This example is the version from Wed, 13th Dec 2016.
Project "Track Line with Data Labels.rbp"
Class App Inherits Application
Const kEditClear = "&Löschen"
Const kFileQuit = "Beenden"
Const kFileQuitShortcut = ""
End Class
Class Window1 Inherits Window
Control Canvas1 Inherits MyControl
ControlInstance Canvas1 Inherits MyControl
End Control
End Class
MenuBar MenuBar1
MenuItem FileMenu = "&Ablage"
MenuItem FileQuit = "#App.kFileQuit"
MenuItem EditMenu = "&Bearbeiten"
MenuItem EditUndo = "&Rückgängig"
MenuItem UntitledMenu1 = "-"
MenuItem EditCut = "&Ausschneiden"
MenuItem EditCopy = "&Kopieren"
MenuItem EditPaste = "&Einfügen"
MenuItem EditClear = "#App.kEditClear"
MenuItem UntitledMenu0 = "-"
MenuItem EditSelectAll = "&Alles auswählen"
End MenuBar
Class MyControl Inherits Canvas
EventHandler Sub MouseMove(X As Integer, Y As Integer) trackLineLegend x pic = c.makeChartPicture me.Invalidate End EventHandler
EventHandler Sub Open() // Data for the chart as 3 random data series dim r as new CDRanSeriesMBS(127) dim data0() as double = r.getSeries(100, 100, -15, 15) dim data1() as double = r.getSeries(100, 150, -15, 15) dim data2() as double = r.getSeries(100, 200, -15, 15) dim timeStamps() as double = r.getDateSeries(100, CDBaseChartMBS.chartTime(2011, 1, 1), 86400, false) // Create a XYChart object of size 640 x 400 pixels c = new CDXYChartMBS(640, 400) // Add a title to the chart using 18 pts Times New Roman Bold Italic font call c.addTitle(" Product Line Global Revenue", "timesbi.ttf", 18) // Set the plotarea at (50, 55) with width 70 pixels less than chart width, and height 90 pixels // less than chart height. Use a vertical gradient from light blue (f0f6ff) to sky blue (a0c0ff) // as background. Set border to transparent and grid lines to white (ffffff). call c.setPlotArea(50, 55, c.getWidth - 70, c.getHeight - 90, c.linearGradientColor(0, 55, 0, c.getHeight - 35, &hf0f6ff, &ha0c0ff), -1, CDBaseChartMBS.kTransparent, &hffffff, &hffffff) // Add a legend box at (50, 25) using horizontal layout. Use 10pts Arial Bold as font. Set the // background and border color to Transparent. c.addLegend(50, 25, false, "arialbd.ttf", 10).setBackground(CDBaseChartMBS.kTransparent) // Set axis label style to 8pts Arial Bold call c.xAxis.setLabelStyle("arialbd.ttf", 8) call c.yAxis.setLabelStyle("arialbd.ttf", 8) // Set the axis stem to transparent c.xAxis.setColors(CDBaseChartMBS.kTransparent) c.yAxis.setColors(CDBaseChartMBS.kTransparent) // Configure x-axis label format call c.xAxis.setMultiFormat(CDBaseChartMBS.StartOfYearFilter, "{value|mm/yyyy} ", CDBaseChartMBS.StartOfMonthFilter, "{value|mm}") // Add axis title using 10pts Arial Bold Italic font call c.yAxis.setTitle("USD millions", "arialbi.ttf", 10) // Add a line layer to the chart using a line width of 2 pixels. dim layer as CDLineLayerMBS = c.addLineLayer layer.setLineWidth(2) // Add 3 data series to the line layer call layer.setXData(timeStamps) call layer.addDataSet(data0, &hff3333, "Alpha") call layer.addDataSet(data1, &h008800, "Beta") call layer.addDataSet(data2, &h3333cc, "Gamma") // Assign the chart to the WinChartViewer pic = c.makeChartPicture me.Invalidate // fix some properties if set wrong in IDE me.DoubleBuffer = false me.EraseBackground = false #if RBVersion >= 2013.0 then me.Transparent = False #endif End EventHandler
EventHandler Sub Paint(g As Graphics, areas() As REALbasic.Rect) if pic <> nil then g.DrawPicture pic, 0, 0 end if End EventHandler
Sub trackLineLegend(mouseX as integer) // Clear the current dynamic layer and get the DrawArea object to draw on it. dim d as CDDrawAreaMBS = c.initDynamicLayer // The plot area object dim plotArea AS CDPlotAreaMBS = c.getPlotArea // check if we are outside the plotArea if mousex<plotArea.getLeftX then Return if mousey<plotArea.getTopY then Return if mousex>plotArea.getRightX then Return if mousey>plotArea.getBottomY then Return // Get the data x-value that is nearest to the mouse, and find its pixel coordinate. dim xValue as double = c.getNearestXValue(mouseX) dim xCoor as integer = c.getXCoor(xValue) // Draw a vertical track line at the x-position d.vline(plotArea.getTopY, plotArea.getBottomY, xCoor, d.dashLineColor(&h000000, &h0101)) // Draw a label on the x-axis to show the track line position. dim xlabel as string xlabel = "<*font,bgColor=000000*> " + c.xAxis.getFormattedLabel(xValue, "mmm dd, yyyy") + " <*/font*>" dim t as CDTTFTextMBS = d.text(xlabel, "arialbd.ttf", 8) // Restrict the x-pixel position of the label to make sure it stays inside the chart image. dim xLabelPos as integer = max(0, min(xCoor - t.getWidth / 2, c.getWidth - t.getWidth)) t.draw(xLabelPos, plotArea.getBottomY + 6, &hffffff) t.destroy // Iterate through all layers to draw the data labels dim u as integer = c.getLayerCount-1 for i as integer = 0 to u dim layer as CDLayerMBS = c.getLayerByZ(i) // The data array index of the x-value dim xIndex as integer = layer.getXIndexOf(xValue) // Iterate through all the data sets in the layer dim uu as integer = layer.getDataSetCount-1 for j as integer = 0 to uu dim dataSet as CDDataSetMBS = layer.getDataSetByZ(j) dim dataSetName as string = dataSet.getDataName // Get the color, name and position of the data label dim colorvalue as integer = dataSet.getDataColor dim yCoor as integer = c.getYCoor(dataSet.getPosition(xIndex), dataSet.getUseYAxis) // Draw a track dot with a label next to it for visible data points in the plot area if ((yCoor >= plotArea.getTopY) and (yCoor <= plotArea.getBottomY) and (colorvalue <> CDBaseChartMBS.kTransparent) and dataSetName.len>0) then d.circle(xCoor, yCoor, 4, 4, colorvalue, colorvalue) dim label as string dim h as string = hex(colorvalue) while h.len<6 h = "0" + h wend label = "<*font,bgColor=" + h + "*> " + c.formatValue(dataSet.getValue(xIndex), "{value|P4}") + " <*font*>" t = d.text(label, "arialbd.ttf", 8) // Draw the label on the right side of the dot if the mouse is on the left side the // chart, and vice versa. This ensures the label will not go outside the chart image. if (xCoor <= (plotArea.getLeftX + plotArea.getRightX) / 2) then t.draw(xCoor + 5, yCoor, &hffffff, CDBaseChartMBS.kLeft) else t.draw(xCoor - 5, yCoor, &hffffff, CDBaseChartMBS.kRight) t.destroy end if end if next next End Sub
Note "Notes"
This sample program demonstrates a track cursor programmed with the following features: * A vertical line that follows the mouse cursor on the plot area and snaps to the nearest x data value, with a label on the x-axis displaying that value. * Small dots that shows the data points at the nearest x data value. * Labels beside the small dots displaying the values of the data points. The code first draws the chart. We hide tracking if mouse is out of plotarea. The track cursor is configured to automatically hide itself when the mouse leaves the plot area. The trackLineLabel method is the routine that draws the track cursor. Its key elements are: * To draw dynamic contents on the chart, the code obtains the DrawArea object for drawing on the dynamic layer of the chart using BaseChart.initDynamicLayer. * The nearest x data value is obtained using XYChart.getNearestXValue. * A vertical line is drawn at the nearest x data value using DrawArea.vline. * The x-axis label at the nearest x value is drawn using DrawArea.text. * The code then iterates through all data sets in all layers to find all the data points at the nearest x data value. For each of these points, it gets the point's y position using DataSet.getPosition, and draws a circular dot using DrawArea.circle. It also formats the point's data value (obtained using DataSet.getValue) and displays it next to the dot using DrawArea.text.
Property c As CDXYChartMBS
Property pic As Picture
End Class
End Project

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The items on this page are in the following plugins: MBS ChartDirector Plugin.

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