ChartDirector 7.0 (Python Edition)

Percentage Bar Chart




This example demonstrates creating a percentage bar chart with a legend box. It also demonstrates gradient background color, rounded frame, soft drop shadow, and using CDML to include custom icons in the legend box.

A percentage bar chart is like a stacked bar chart, except the bars are individually scaled so that they stacked up to 100.

The key features demonstrated in this example are:

Note that by default, the data label format is {percent}% (showing the percentage) for a percentage bar layer, as opposed to {value} (showing the data value) for other types of bar layer. The data label format can be modified using Layer.setDataLabelFormat.

Source Code Listing

pythondemo\percentbar.py
#!/usr/bin/python # The ChartDirector for Python module is assumed to be in "../lib" import sys, os sys.path.insert(0, os.path.join(os.path.abspath(sys.path[0]), "..", "lib")) from pychartdir import * # The data for the bar chart data0 = [100, 125, 245, 147, 67] data1 = [85, 156, 179, 211, 123] data2 = [97, 87, 56, 267, 157] # The labels for the bar chart labels = ["Mon", "Tue", "Wed", "Thu", "Fri"] # Create a XYChart object of size 500 x 320 pixels. Use a vertical gradient color from pale blue # (e8f0f8) to sky blue (aaccff) spanning half the chart height as background. Set border to blue # (88aaee). Use rounded corners. Enable soft drop shadow. c = XYChart(500, 320) c.setBackground(c.linearGradientColor(0, 0, 0, c.getHeight() / 2, 0xe8f0f8, 0xaaccff), 0x88aaee) c.setRoundedFrame() c.setDropShadow() # Add a title to the chart using 15 points Arial Italic. Set top/bottom margins to 15 pixels. title = c.addTitle("Weekly Product Sales", "Arial Italic", 15) title.setMargin2(0, 0, 15, 15) # Tentatively set the plotarea to 50 pixels from the left edge, and to just under the title. Set the # width to 60% of the chart width, and the height to 50 pixels from the bottom edge. Use pale blue # (e8f0f8) background, transparent border, and grey (aaaaaa) grid lines. c.setPlotArea(50, title.getHeight(), c.getWidth() * 6 / 10, c.getHeight() - title.getHeight() - 50, 0xe8f0f8, -1, Transparent, 0xaaaaaa) # Add a legend box where the top-right corner is anchored at 10 pixels from the right edge, and just # under the title. Use vertical layout and 8 points Arial font. legendBox = c.addLegend(c.getWidth() - 10, title.getHeight(), 1, "Arial", 8) legendBox.setAlignment(TopRight) # Set the legend box background and border to transparent legendBox.setBackground(Transparent, Transparent) # Set the legend box icon size to 16 x 32 pixels to match with custom icon size legendBox.setKeySize(16, 32) # Set axes to transparent c.xAxis().setColors(Transparent) c.yAxis().setColors(Transparent) # Set the labels on the x axis c.xAxis().setLabels(labels) # Add a percentage bar layer layer = c.addBarLayer2(Percentage) # Add the three data sets to the bar layer, using icons images with labels as data set names layer.addDataSet(data0, 0x66aaee, "<*block,valign=absmiddle*><*img=service.png*> Service<*/*>") layer.addDataSet(data1, 0xeebb22, "<*block,valign=absmiddle*><*img=software.png*> Software<*/*>") layer.addDataSet(data2, 0xcc88ff, "<*block,valign=absmiddle*><*img=computer.png*> Hardware<*/*>") # Use soft lighting effect with light direction from top layer.setBorderColor(Transparent, softLighting(Top)) # Enable data label at the middle of the the bar layer.setDataLabelStyle().setAlignment(Center) # For a vertical stacked chart with positive data only, the last data set is always on top. However, # in a vertical legend box, the last data set is at the bottom. This can be reversed by using the # setLegend method. layer.setLegend(ReverseLegend) # Adjust the plot area size, such that the bounding box (inclusive of axes) is 15 pixels from the # left edge, just below the title, 10 pixels to the right of the legend box, and 15 pixels from the # bottom edge. c.packPlotArea(15, title.getHeight(), c.layoutLegend().getLeftX() - 10, c.getHeight() - 15) # Output the chart c.makeChart("percentbar.png")