iOS NSString causing memory leak

[man2manno]

Hey guys,

I built part of my app and sometimes when I run it, it works fine other times when I push a button that retrieves a global NSString value makes the app crash. The only thing I can think is that this caused by a memory leak from the NSString. I believe I have it initialized correctly and I am releasing it in the dealloc method.

Any ideas?

RootViewController.h

@interface RootViewController: UIViewController {
	
	// Declare the text views for viewing the messages on the app
	IBOutlet UILabel *latestTxtView;
	IBOutlet UILabel *unreadTxtView;
	
	// Declare buttons for retrieving the messages
	IBOutlet UIButton *latestTxtButton;
	IBOutlet UIButton *sendButton;
	
	// Declare string to hold values to be sent out
	NSString *latestTxt;
}

@property(nonatomic,retain)IBOutlet UITextView *latestTxtView;
@property(nonatomic,retain)IBOutlet UITextView *unreadTxtView;
@property(nonatomic,retain)IBOutlet UIButton *latestTxtButton;

@property(nonatomic,retain)IBOutlet UIButton *sendButton;

@property(nonatomic,retain)NSString *latestTxt;

// Action Items for the buttons
- (IBAction)getLatestTxt:(id)sender;
- (IBAction)pushSendButton:(id)sender;
@end

RootViewController.m

@implementation RootViewController
@synthesize latestTxtView, unreadTxtView, latestTxtButton, sendButton, latestTxt;

- (IBAction)getLatestTxt:(id)sender {
    ....
    latestTxt = [NSString stringWithCString:contentTxt encoding:NSUTF8StringEncoding];
    ....
}

- (IBAction)pushSendButton:(id)sender {
   ....
   unreadTxtView.text = latestTxt; // I believe this is the leak
}
@end

It is also important to note that in the app delegate I am calling the dealloc method...

- (void)dealloc {
	
    [_latestTxt release];
    
    [_latestTxtView release];
    [_latestTxtButton release];
    
    [_unreadTxtView release];
    
	[_viewController release];
	[_window release];
	[super dealloc];
}

Any ideas where this leak may be coming from? Have I properly defined/declared a global NSString?

Thanks!

 

[dejo]

RootViewController.m

    latestTxt = [NSString stringWithCString:contentTxt encoding:NSUTF8StringEncoding];

If you define a property for latestTxt, you should reference it using self, as in:

self.latestTxt = [NSString stringWithCString:contentTxt encoding:NSUTF8StringEncoding];

It is also important to note that in the app delegate I am calling the dealloc method...

- (void)dealloc {
	
    [_latestTxt release];
    
    [_latestTxtView release];
    [_latestTxtButton release];
    
    [_unreadTxtView release];
    
	[_viewController release];
	[_window release];
	[super dealloc];
}

You should have this dealloc in your RootViewController's class.

Have I properly defined/declared a global NSString?

Which NSString do you think you've define as global? I don't see one.

P.S. I see you're not using ARC. Any particular reason why?

 

[man2manno]

Thanks for the help.

Well I thought by declaring latestTxt in the header I was making it global, is that not correct?

I didn't think the ARC was needed for this program seeing that I am really only intending the change the value of the string one time. Maybe my understanding of the auto reference counting is not accurate.