[Pythonmac-SIG] Cocoa graphics and context management

[Etienne Posthumus]

On dinsdag, sep 16, 2003, at 12:29 Europe/Amsterdam, Dinu Gherman wrote:
> I suspect this is because of some graphics context I don't care at
> all about, isn't it? Does anybody have an idea how to improve this?

Hi Dinu

I am just a starting to get my head around Cocoa so take everything I 
say with a bag of salt... :-)
I think the error messages are because there is no connection to the 
window server.
You need to set up an NSApp and make a window for the view to be 
connected to.
I have added some lines of code, and then it runs the test without 
errors.
Try the script as changed below.

gr.

Etienne



#!/usr/bin/env python

"test_nsview.py - saving simple Cocoa graphics in a PDF file."


import os, unittest

from objc import YES, NO
from AppKit import NSView, NSColor, NSBezierPath, NSWindow
import AppKit

class MyView(NSView):
     "A simple view containing a blue filled ellipse."

     def drawRect_(self, aRect):
         col = NSColor.blueColor()
         col.set()
         path = NSBezierPath.bezierPathWithOvalInRect_(aRect)
         path.setLineWidth_(0)
         path.stroke()
         path.fill()


class TestNSView(unittest.TestCase):

     def test0(self):
         "Create a simple graphic PDF file."
         my_window = NSWindow.alloc()
         my_window.initWithContentRect_styleMask_backing_defer_( ((0, 
0), (200, 100)) , 0, AppKit.NSBackingStoreBuffered, NO)

         path = "test_nsview0.pdf"
         if os.path.exists(path):
             os.remove(path)

         # create a view
         frame = ((0,0), (200, 100))
         view = MyView.alloc().initWithFrame_(frame)
         my_window.setContentView_(view)

         view.drawRect_(frame)
         # save it
         pdfData = view.dataWithPDFInsideRect_(frame)
         pdfData.writeToFile_atomically_(path, YES)

         self.assert_(os.path.exists(path), "PDF not saved!")

if __name__=='__main__':
     NSApp = AppKit.NSApplication.sharedApplication()
     unittest.main()