EasyDialogs has a working version of this.

Mac/Lib/test/progressbar.py

@@ -1,25 +0,0 @@
-# Progress dialog
-
-from Dlg import GetNewDialog, ModalDialog, SetDialogItemText
-
-count = 0
-
-def filter(d, e):
-	r = 1
-	print "Filter(%s, %s) -> %s" % (`d`, `e`, `r`)
-	return r
-
-def main():
-	d = GetNewDialog(256, -1)
-	tp, h, rect = d.GetDialogItem(2)
-	SetDialogItemText(h, "Progress...")
-	for i in range(100):
-		if i%10 == 0:
-			str = "Progress...%d" % i
-			SetDialogItemText(h, str)
-			ModalDialog(filter)
-		for j in range(100): pass
-
-if __name__ == '__main__':
-	main()
-