[Pyobjc-dev] Attempt at writing Cocoa services with pyobjc

[Dinu G. <gh...@da...>]

Hi,

After recently seeing the release of pyobjc 0.8 I decided it was
high time to have some fun writing *real* Python Cocoa programs!

I started using pyobjc on a little Cocoa Services tool, much in
the spirit of URLServices for those who know it. Unfortunately,
I can't find a URL for downloading it, but I can provide my copy
of it to anybody interested.

There are two problems I'm having so far with that first toy pro-
ject, after just creating a "Python Cocoa App." with PB:

1. Removing the PB Resources folder containing the MainMenu.nib
and InfoPlist.strings results in complaints like "Unable to load nib
file: MainMenu, exiting". The NIB file isn't needed in this case as
there is neither a GUI nor an app "owner" object, hence I also re-
moved the MyAppDelegate.py thinking that would be ok. Apparently
there must be something else to get rid of the need for a NIB file.
Any ideas?

2. In the Python main file I fumbled to port the code from the
URLServices project inside this function:

	int main(int argc, const char **argv)
	{
	  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
	  URLServices *serviceProvider = [[URLServices alloc] init];
	
	  NSRegisterServicesProvider(serviceProvider, @"URLServices");
	
	  NS_DURING
	    [[NSRunLoop currentRunLoop] configureAsServer];
	    [[NSRunLoop currentRunLoop] run];
	  NS_HANDLER
	    NSLog(@"%@", localException);
	  NS_ENDHANDLER
	
	  [serviceProvider release];
	  [pool release];
	
	  exit(0);
	  return 0;
	}


to something like the following:

	# import classes required to start application
	import PyServices
	
	from Foundation import NSAutoreleasePool, NSRunLoop, NSLog
	from AppKit import NSRegisterServicesProvider
	
	# stuff ported from URLServices' main.m
	## pool = NSAutoreleasePool.alloc().init()
	serviceProvider = PyServices.PyServices.alloc().init()
	NSRegisterServicesProvider(serviceProvider, "PyServices")
	#  NS_DURING
	NSRunLoop.currentRunLoop().configureAsServer()
	NSRunLoop.currentRunLoop().run()
	#  NS_HANDLER
	NSLog("%@", localException)
	#  NS_ENDHANDLER
	serviceProvider.release()
	## pool.release()
	
	# pass control to the AppKit (from template __main__.py)
	# import sys
	# sys.exit(AppKit.NSApplicationMain(sys.argv))

where it seems that using the autorelease pool is a bad idea (com-
plains with "Cannot retain an autorelease pool") and replacing the
NSApplicationMain function with an NSRunLoop does not quite seem
to work like expected, resulting in crash reports being dumped.

I'm barely beginning to really play with pyobjc and so I don't have
a detailed idea yet of how it works, while at the same time I'm un-
dusting some Cocoa knowledge... Since it is only some 15 KB I dare
to attach my initial code here right away.

If anybody can give a helping hand this could be a nice demo for
pyobjc since text, URL and file management is *much* easier in Py-
thon than in the Foundation Kit...

Regards,

Dinu

PS: BTW, this is Apple's online info about how to create services:
      
http://developer.apple.com/techpubs/macosx/Cocoa/TasksAndConcepts/ 
ProgrammingTopics/SysServices/index.html

--
Dinu C. Gherman
......................................................................
"Women give to men the very gold of their lives. But they invariably
want it back in small change." (Oscar Wilde)