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PONSArray returning NULL value even though right number of objects is counted and returned
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copied!<p>I have created a NSArray that contains images objects. Based on the swipe direction recognized by UISwipeGestureRecognizerDirection the index is incremented up or down so the right image could be selected.</p> <p>The problem I have is that my NSArray is returning a NULL value instead of the image object. Therefore the UIImageView (named imageView) displays nothing.</p> <p>I am printing an NSLog statement in order to see what is really happening - example below:</p> <p>... [2307:60b] Swiped and the index is: 1, the image is (null) and the total number of objects 2</p> <p>As per NSLog statement above we can see that: - The number of objects is perfectly counted. - NSArray index increments perfectly up and down. - But a NULL value is returned for the image object.</p> <p>My code below (see the handleSwipe method):</p> <pre><code>@synthesize imageView; int imageIndex = 1; - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view. self.view.backgroundColor = [UIColor whiteColor]; imageView.center = CGPointMake(CGRectGetWidth(self.view.bounds)/2.0f, CGRectGetHeight(self.view.bounds)/2.0f+20); [self.view addSubview:imageView]; UISwipeGestureRecognizer *swipeRightGesture=[[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleSwipe:)]; [self.view addGestureRecognizer:swipeRightGesture]; swipeRightGesture.direction = UISwipeGestureRecognizerDirectionRight; UISwipeGestureRecognizer *swipeLeftGesture=[[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleSwipe:)]; [self.view addGestureRecognizer:swipeLeftGesture]; swipeRightGesture.direction = UISwipeGestureRecognizerDirectionLeft; UIBarButtonItem *dismiss_btn = [[UIBarButtonItem alloc] initWithTitle:@"Done" style:UIBarButtonItemStylePlain target:self action:@selector(dismissModal:)]; self.navigationItem.rightBarButtonItems = [NSMutableArray arrayWithObjects:dismiss_btn, nil]; } - (IBAction)handleSwipe:(UIGestureRecognizer *)sender { int theTotal; NSArray *images=[[NSArray alloc] initWithObjects: @"image021.jpg", @"image041.jpg", nil]; UISwipeGestureRecognizerDirection direction = [(UISwipeGestureRecognizer *) sender direction]; switch (direction) { case UISwipeGestureRecognizerDirectionLeft: imageIndex++; break; case UISwipeGestureRecognizerDirectionRight: imageIndex--; break; default: break; } imageIndex = (imageIndex < 0) ? ([images count] -1): imageIndex % [images count]; imageView.image = [UIImage imageNamed:[images objectAtIndex:imageIndex]]; theTotal = [images count]; NSLog(@"Swiped and the index is: %d, the image is %@ and the total number of objects %d", imageIndex, imageView.image, theTotal); } </code></pre>

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