Method causing a weird crash

Answer 1

This is just a guess, as not all of the code is there. In your init method for the Transaction class, do you make sure to retain the strings? (category and description).

The thing that stands out to me is that you initialize the Transaction, then release the categoryString immediately after. If you're not retaining the string, then this could be the source of your crash.

On a side note, you are leaking memory. Here:

NSString *descriptionString = [[NSString alloc] init];
descriptionString = descriptionField.text;

descriptionString is pointing to a newly allocating string, only to be reassigned to an existing string, so the first string is leaked. You should change this to:

NSString *descriptionString;
descriptionString = descriptionField.text;

or more simply:

NSString *descriptionString = descriptionField.text;

Answer 2

This is wrong:

NSIndexPath *indexPath = [[NSIndexPath alloc] init];
indexPath = [self.categoryTableView indexPathForSelectedRow];

NSInteger selectedCategory = indexPath.row;
[indexPath release];

You're instantiating an empty NSIndexPath and then overwriting the reference to it. The release on the last line is sent to an entirely different object returned by the table view. The object you create is never used and never released.

This will work:

NSIndexPath *indexPath = [self.categoryTableView indexPathForSelectedRow];
NSInteger selectedCategory = indexPath.row;

You're not creating an NSIndexPath object, so you have no responsibility to release it.

(your unnecessary release is causing the index path instance to be prematurely deallocated. When Apple's code tries to release the object, it no longer exists, and the app crashes)