pushViewController memory leak - iphone

Question

I have following code, instrument indicate that the pushViewController method has 32 bytes memory leak on device. Could you please kindly help check what rule I break? Should I change some "retain" to "assign" for declaration? Thanks in advance!
#interface GuideNewsViewController : UIViewController <UITableViewDataSource, UITableViewDelegate> {
#private
NSFetchedResultsController *fetchedResultsController;
NSManagedObjectContext *managedObjectContext;
UITableView *tableView;
NewsListViewController *newsListViewController;
}
#property (nonatomic, retain) NSManagedObjectContext *managedObjectContext;
#property (nonatomic, retain, readonly) NSFetchedResultsController *fetchedResultsController;
#property (nonatomic, retain) UITableView *tableView;
#property (nonatomic, retain, readonly) NewsListViewController *newsListViewController;
#implementation GuideNewsViewController
......
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
Member *member = [fetchedResultsController objectAtIndexPath:indexPath];
self.newsListViewController.managedObjectContext = self.managedObjectContext;
self.newsListViewController.title = member.memberName;
self.newsListViewController.author = member;
**// leak here**
[self.navigationController pushViewController:self.newsListViewController animated:YES];
}
......
#end
#interface NewsListViewController : UIViewController <UITableViewDataSource, UITableViewDelegate> {
#private
NSFetchedResultsController *fetchedResultsController;
NSManagedObjectContext *managedObjectContext;
UITableView *tableView;
Member *author;
}
#property (nonatomic, assign) NSManagedObjectContext *managedObjectContext;
#property (nonatomic, retain) UITableView *tableView;
#property (nonatomic, assign, readonly) NSFetchedResultsController *fetchedResultsController;
#property (nonatomic, assign) Member *author;
#end

Answer 1

Just a guess but, what happen if you change your newsListViewController from retain to assign?
I barely write retain, readonly together.

Answer 2

When does self.newsListViewController be released ? I don't think that point causes problem.
Generally, I pushViewController with following manner.
MySelfViewController *childView = [[MySelfViewController alloc] init];
// set up necessary properties of childView
...
// navigationController will release childView when it pops view controller.
[self pushViewController:childView animated:YES];
// release childView after pushViewController
[childView release];
If childView have to notify self something happened, it can use delegate to notify self.
Edit 1:
An example is as following.
// MySelfViewController.h
#protocol MySelfProtocol <NSObject>
- (void)notifySomethingHappened;
#end
#interface MySelfViewController : UIViewController {
id <MySelfProtocol> _delegate;
}
/// client init childview by pass self as parameter.
/// ex: Inside view controller A, he calls by
/// childView = [[MySelfViewController alloc] initWithDelegate:self];
- (id)initWithDelegate:(id)delegate;
/// other member methods
#end
// MySelfViewController.m
#implement MySelfViewController
- (id)initWithDelegate:(id)delegate
{
if (self = [super init])
{
/// assign policy.
/// childView should not retain parent view or delegate.
/// It is possible to let delegate never run dealloc.
_delegate = delegate;
/// custom initialization
....
}
return self;
}
- (void)someThingHappen
{
[_delegate notifySomethingHappend];
}
#end