----- Original Message ----- From: <hpinson@indepthl.com>

Has anyone gotten the (excellent) ChartDirector charting library to work with zope?

Here's what I have tried:

1. Created an ExternalMethod named barchart.py, in the Extensions folder: #output the chart print "Content-type: image/png\n" binaryPrint(c.makeChart2(PNG))

Where is 'binaryPrint' printing to (a file? stdio?)? I am not familiar with ChartDirector, but with PIL we have to trick it to write to a 'ram file' and then return that, here are the relevant extracts from an external method that uses PIL: <snip> class RamFile: def __init__(self): self.contents = [] def write(self,s): self.contents.append(s) def read(self): return string.join(self.contents,'') </snip> <snip> canvas.drawString("S", 7,263, Font(face="times",size=14,bold=1), color=black, angle=0) canvas.flush() rfile = RamFile() canvas.save(file=rfile,format="jpeg") return rfile.read() </snip> HTH Jonathan

Hi Harlow, You're getting confused because you have a cgi environment. An externbal method is a "Zope thing" though, it needs to return whatever you want Zope to return to the browser... hpinson@indepthl.com wrote:

#!/usr/bin/python2.3

You don't need this, this will never be executed as a script.

def drawBarChart():

from pychartdir import *

from cStringIO imort StringIO output = StringIO()

#The data for the bar chart data = [85, 156, 179.5, 211, 123]

#The labels for the bar chart labels = ["Mon", "Tue", "Wed", "Thu", "Fri"]

#Create a XYChart object of size 250 x 250 pixels c = XYChart(250, 250)

#Set the plotarea at (30, 20) and of size 200 x 200 pixels c.setPlotArea(30, 20, 200, 200)

#Add a bar chart layer using the given data c.addBarLayer(data)

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

#output the chart

print >> output, "Content-type: image/png\n"

binaryPrint(c.makeChart2(PNG))

# you need to get the above to append what it generates to 'output'. return output.getvalue() cheers, Chris -- Simplistix - Content Management, Zope & Python Consulting - http://www.simplistix.co.uk