Question

I am pushing an object on navigation controller but when I return the control from the that view controller it crashes the app.

[self.navigationController pushViewController:chequeDetails animated:YES];
        [chequeDetails release];

but when I write the same code with

[self.navigationController pushViewController:chequeDetails animated:YES];
 chequeDetails=nil;
[chequeDetails release];

The app does not crash but a slight lag is observed… when i pop back from the check details controller?

Answer 1

If your seconds exaple code, you are not release the chequeDetails since calling release on a nil object does not nothing:

[self.navigationController pushViewController:chequeDetails animated:YES];
 chequeDetails=nil;
// calling the release on nill will do nothing
[chequeDetails release];

Normally you can do it this ways:

[self.navigationController pushViewController:chequeDetails animated:YES];
[chequeDetails release], chequeDetails = nil;

But only release the chequeDetails if you did a alloc, init like:

ChequeDetails *chequeDetails = [[ChequeDetails alloc] initWithNibName:@"ChequeDetails" bundle:nil];

So the full code should be something like:

ChequeDetails *chequeDetails = [[ChequeDetails alloc] initWithNibName:@"ChequeDetails" bundle:nil];
[self.navigationController pushViewController:chequeDetails animated:YES];
[chequeDetails release], chequeDetails = nil;