NSInvalidArgumentException when posting notification - cocoa-touch

Question

I am trying to use the notification system in order to have a detail view in a Splitviewcontroller to update the tableview. I declared the notification as follows:
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(pushView:) name:#"pushView" object:nil];
and the selector itself:
- (void) pushView:(UIViewController *) viewController {
[self.navigationController pushViewController:viewController animated:YES];
}
Now, in the detailview I create the view-controller and call create the notification:
ArticleTableViewController *articleTableView = [[ArticleTableViewController alloc] initWithCategory:catInt];
[[NSNotificationCenter defaultCenter] postNotificationName:#"pushView" object:articleTableView];
I assumed that that would work, but I get the error:
* Terminating app due to uncaught
exception
'NSInvalidArgumentException', reason:
'-[NSConcreteNotification
setParentViewController:]:
unrecognized selector sent to instance
0x5a3a290'
So I guess I am doing something wrong in how including the detailViewController in the notification to be used to push in.

Answer 1

The method definition for handling the notification seems to be wrong.
- (void) pushView:(UIViewController *) viewController
should be,
- (void) pushView:(NSNotification *) notification
The actual notification is passed as the argument, not any view controllers. To achieve what you want, try the following.
- (void) pushView:(NSNotification *) notification
NSDictionary *userInfo = [notification userInfo];
UIViewController *viewController = (UIViewController *)[userInfo objectForKey:#"ViewController"];
[self.navigationController pushViewController:viewController animated:YES];
}
And while posting the notification,
ArticleTableViewController *articleTableView = [[ArticleTableViewController alloc] initWithCategory:catInt];
NSDictionary *userInfo = [NSDictionary dictionaryWithObject:articleTableView forKey:#"ViewController"];
[[NSNotificationCenter defaultCenter] postNotificationName:#"pushView" object:nil userInfo:userInfo];