pushViewController crahses

Question

I'm trying to push a new view on my navigation controller using:

    -(IBAction)switchPage:(id)sender
{
 MyTableViewController *myTableView = [[CMyTableViewController alloc] initWithNibName:@"MyTableView" bundle:[NSBundle mainBundle]];
 [myTableView release];
 [self.navigationController pushViewController:myTableView animated:YES];
}

I'm running into the following error:

2010-02-25 21:19:57.717 CoC[3399:20b] *** -[UIViewController switchPage:]: unrecognized selector sent to instance 0xf1a660
2010-02-25 21:19:57.718 CoC[3399:20b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[UIViewController switchPage:]: unrecognized selector sent to instance 0xf1a660'

Answer 1

you are releasing an object you just allocated which makes no sense.

 MyTableViewController *myTableView = [[CMyTableViewController alloc] initWithNibName:@"MyTableView" bundle:[NSBundle mainBundle]];
     [myTableView release];

release myTableView after you push it onto the stack

Answer 2

Call release after pushing.

Answer 3

2010-02-25 21:19:57.717 CoC[3399:20b] * ** -[UIViewController switchPage:]: unrecognized selector sent to instance 0xf1a660

Your crash not because of the code what you have mentioned. But there is a bug in you code like release and thenpush. Change it as:

 -(IBAction)switchPage:(id)sender
{
 MyTableViewController *myTableView = [[CMyTableViewController alloc] initWithNibName:@"MyTableView" bundle:[NSBundle mainBundle]];
 [self.navigationController pushViewController:myTableView animated:YES];
 [myTableView release];
}

I guess the object which is calling "switchPage:" method is having some problem. Check it or show the invocation of this method for any help

Regards, Manjunath

Answer 4

Above is alright,when the subview controller has been pushed into the nav's stack,the retain count should be increased,then you should release it after the push operation.

Answer 5

Are you sure you don't need to swap last two lines? First push controller, then release it not visa versa... :)

Answer 6

As mentioned earlier, you release the view controller before you push it. When you push it onto the navigation controller, the retain count is increased, and then you can release it.

-(IBAction)switchPage:(id)sender
{
     MyTableViewController *myTableView = [[MyTableViewController alloc] initWithNibName:@"MyTableView" bundle:[NSBundle mainBundle]];
    [self.navigationController pushViewController:myTableView animated:YES];
    [myTableView release];
}