NSNotifications

I want to send information between two running applications and I mistakenly thought I could use an NSNotification to do this. [See the UPDATE].

So this post is about the first step, getting an NSNotification to work within a running app. The following is from an Xcode Cocoa-Python app, and in AppDelegate.py we have:

from Foundation import * from AppKit import * import objc class SpeakAppDelegate(NSObject): def applicationDidFinishLaunching_(self, sender): NSLog("Application really did finish launching.") nc = NSNotificationCenter.defaultCenter() nc.addObserver_selector_name_object_( self, "mycallback:", 'love_note', None) @objc.signature('v@0:@8') def mycallback_(self,note): print 'note' print note.description() @objc.IBAction def button_(self,sender): print sender, 'button' nc = NSNotificationCenter.defaultCenter() nc.postNotificationName_object_userInfo_( 'love_note', None, {'path':'xyz'})

There's a button in the window hooked up to the IBAction. I push the button and get:

<NSButton: 0x61c7b0> button note NSConcreteNotification 0x6337a0 {name = love_note; userInfo = { path = xyz; }}

But I couldn't get it to work between apps, for example with this one compiled in Terminal:

// gcc tell.m -o test -framework Foundation #import <Foundation/Foundation.h> int main() { NSNotificationCenter *nc; nc = [NSNotificationCenter defaultCenter]; [nc postNotificationName:@"love_note" object:nil userInfo:nil ]; return 0; }

I asked on Stack Overflow (here), and they say I should be using Distributed Objects (here). So I have to look into that.

[ UPDATE: Just substitute NSDistributedNotificationCenter in the code above. It works! ]