transitionWithView gets called repeatedly after ViewController is dismissed

Question

This is in a ModalViewController using StoryBoard and ARC

When I dismiss the view I see this line... NSLog(@"%d %@",[imgArray count],fileName); ... being printed over and over again.

How do I kill the functions transitionWithView/animateWithDuration when the view is dismissed?

Missing something quite crucial!

.h

#import <UIKit/UIKit.h>

@interface InfoVC : UIViewController

@property (weak, nonatomic) IBOutlet UIImageView *imageview;
@property (weak, nonatomic) IBOutlet UIScrollView *scrollview;

@end

.m

#import "InfoVC.h"
#import <QuartzCore/QuartzCore.h>

@interface InfoVC ()

@end

@implementation InfoVC {
    int randomInt;
    NSArray *imgs;
    NSMutableArray *imgArray;
    NSTimer *myTimer;
    NSTimer *myTimer2;
    NSString *currentImg;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    imgs = [NSArray arrayWithObjects:
                      @"01.jpg",
                      @"02.jpg",
                      @"03.jpg",
                      nil];
    imgArray = [imgs mutableCopy];
    [self initialImage];
}


- (void)initialImage
{
    _imageview.contentMode = UIViewContentModeLeft;

    int rnd = [imgArray count];
    randomInt = (arc4random()%rnd);
    currentImg = [imgArray objectAtIndex:randomInt];    
    UIImage *image = [UIImage imageNamed:currentImg];

    [_imageview setImage:image];
    _imageview.bounds = CGRectMake(0, 0, image.size.width, image.size.height);

    _scrollview.contentSize = image.size;
    _scrollview.contentOffset = CGPointMake(-150.0, 0.0);

    [imgArray removeObjectAtIndex: randomInt];

    [self animate];
}

- (void)randomImage
{        
    if ([imgArray count]==0) {
        imgArray = [imgs mutableCopy];
    }

    int rnd = [imgArray count];
    randomInt = (arc4random()%rnd);
    NSString *fileName = [imgArray objectAtIndex:randomInt];

    NSLog(@"%d %@",[imgArray count],fileName);

    [imgArray removeObjectAtIndex: randomInt];

    UIImage * toImage = [UIImage imageNamed:fileName];


    void (^completion)(void) = ^{
        [self animate];
    };

    [UIView transitionWithView:self.view
                      duration:1.75f
                       options:UIViewAnimationOptionTransitionCrossDissolve | UIViewAnimationOptionAllowUserInteraction
                    animations:^
                    {
                        _imageview.image = toImage;
                    }
                    completion:^(BOOL finished)
                    {
                        completion();
                    }
    ];

}

- (void)animate{

    CGPoint offset = _scrollview.contentOffset;

    float flt = 150.0;

    if (_scrollview.contentOffset.x == flt)
    {
        offset.x = 0.0 ;
    }
    else
    {
        offset.x = flt ;
    }

    void (^completion2)(void) = ^{
        [self randomImage];
    };

    [UIView animateWithDuration:5.0 delay:0 options:UIViewAnimationOptionAllowUserInteraction | UIViewAnimationCurveEaseIn
                     animations:^{
                         _scrollview.contentOffset = offset; 
                     }completion:^(BOOL completed){
                         completion2();
                     }
     ];


}

- (void)viewDidUnload
{
    [super viewDidUnload];

    [_scrollview.layer removeAllAnimations];
    [_imageview.layer removeAllAnimations];
}


- (IBAction)dismissInfo:(id)sender
{
    [_scrollview.layer removeAllAnimations];
    [_imageview.layer removeAllAnimations];

    [self dismissModalViewControllerAnimated:YES];
}

your generating the infinite loop by calling one from other and other calling the same called function ..... my suggestion you need to change the model — Arun, Oct 25 '12 at 05:34
Yes I want an infinite loop, it just keeps chugging. Since posting I've nested the two blocks, but the issue is that the randomImage block gets called in rapid succession once the controller is removed - way faster than when the controller is present — JulianB, Oct 25 '12 at 11:23

score 1 · Accepted Answer · edited Nov 15 '12 at 05:42

1

I tried using a gazillion things retro fitting transitionWithView with CABasicAnimation, using NSTimer etc.

In the end I just did:

[_imageview removeFromSuperview];

when dismissing the view and all was great.

But from other posts on here it appears there is a bug hen when applying an alpha transition to a UIScrollview - the reference to the view is lost when it's transparent.

edited Nov 15 '12 at 05:42

Paul Bellora

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answered Nov 09 '12 at 10:19

JulianB

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transitionWithView gets called repeatedly after ViewController is dismissed

1 Answers1