ChartDirector 5.1 (Python Edition)

Background and Wallpaper


      

This example demonstrates some of the background effects supported by ChartDirector.

ChartDirector supports using an image file as the wallpaper of the chart image background with BaseChart.setWallpaper, and as the plot area background with PlotArea.setBackground2.

In addition to wallpapers, ChartDirector supports alternating plot area background colors using PlotArea.setBackground and PlotArea.setAltBgColor.

You can switch the default colors to using a dark background with white lines and text in one step by changing the color palette to a whiteOnBlackPalette using BaseChart.setColors.

Source Code Listing

[Standalone Version] pythondemo\background.py
#!/usr/bin/python
from pychartdir import *

def createChart(img) :

    # The data for the chart
    data = [85, 156, 179.5, 211, 123]
    labels = ["Mon", "Tue", "Wed", "Thu", "Fri"]

    # Create a XYChart object of size 270 x 270 pixels
    c = XYChart(270, 270)

    # Set the plot area at (40, 32) and of size 200 x 200 pixels
    plotarea = c.setPlotArea(40, 32, 200, 200)

    # Set the background style based on the input parameter
    if img == "0" :
        # Has wallpaper image
        c.setWallpaper("tile.gif")
    elif img == "1" :
        # Use a background image as the plot area background
        plotarea.setBackground2("bg.png")
    elif img == "2" :
        # Use white (0xffffff) and grey (0xe0e0e0) as two alternate plotarea
        # background colors
        plotarea.setBackground(0xffffff, 0xe0e0e0)
    else :
        # Use a dark background palette
        c.setColors(whiteOnBlackPalette)

    # Set the labels on the x axis
    c.xAxis().setLabels(labels)

    # Add a color bar layer using the given data. Use a 1 pixel 3D border for the
    # bars.
    c.addBarLayer3(data).setBorderColor(-1, 1)

    # Output the chart
    c.makeChart("background%s.png" % img)


createChart("0")
createChart("1")
createChart("2")
createChart("3")

[CGI Version] pythondemo_cgi\background.py
#!/usr/bin/python
from pychartdir import *
import cgi, os

# Get HTTP query parameters
query = cgi.FieldStorage()

# The data for the chart
data = [85, 156, 179.5, 211, 123]
labels = ["Mon", "Tue", "Wed", "Thu", "Fri"]

# Create a XYChart object of size 270 x 270 pixels
c = XYChart(270, 270)

# Set the plot area at (40, 32) and of size 200 x 200 pixels
plotarea = c.setPlotArea(40, 32, 200, 200)

# Set the background style based on the input parameter
if query["img"].value == "0" :
    # Has wallpaper image
    c.setWallpaper(os.path.join(os.path.dirname(sys.argv[0]), "tile.gif"))
elif query["img"].value == "1" :
    # Use a background image as the plot area background
    plotarea.setBackground2(os.path.join(os.path.dirname(sys.argv[0]), "bg.png"))
elif query["img"].value == "2" :
    # Use white (0xffffff) and grey (0xe0e0e0) as two alternate plotarea background
    # colors
    plotarea.setBackground(0xffffff, 0xe0e0e0)
else :
    # Use a dark background palette
    c.setColors(whiteOnBlackPalette)

# Set the labels on the x axis
c.xAxis().setLabels(labels)

# Add a color bar layer using the given data. Use a 1 pixel 3D border for the bars.
c.addBarLayer3(data).setBorderColor(-1, 1)

# Output the chart
print("Content-type: image/png\n")
binaryPrint(c.makeChart2(PNG))