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iOS Build a Simple iPhone App (iOS7) Animating and Intercepting Events Image Based Animation

Shaun Kelly
Shaun Kelly
5,648 Points

I click on the screen 1 time in the simulator. The animation keeps repeating in an infinite loop ?

#import "ViewController.h"
#import "THCrystalBall.h"
@interface ViewController ()


@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    self.crystalBall = [[THCrystalBall alloc] init];

    self.backgroundImageView.animationImages= [[NSArray alloc] initWithObjects:
                                               [UIImage imageNamed:@"CB00001"],
                                               [UIImage imageNamed:@"CB00002"],
                                               [UIImage imageNamed:@"CB00003"],
                                               [UIImage imageNamed:@"CB00004"],
                                               [UIImage imageNamed:@"CB00005"],
                                               [UIImage imageNamed:@"CB00006"],
                                               [UIImage imageNamed:@"CB00007"],
                                               [UIImage imageNamed:@"CB00008"],
                                               [UIImage imageNamed:@"CB00009"],
                                               [UIImage imageNamed:@"CB00010"],
                                               [UIImage imageNamed:@"CB00011"],
                                               [UIImage imageNamed:@"CB00012"],
                                               [UIImage imageNamed:@"CB00013"],
                                               [UIImage imageNamed:@"CB00014"],
                                               [UIImage imageNamed:@"CB00015"],
                                               [UIImage imageNamed:@"CB00016"],
                                               [UIImage imageNamed:@"CB00017"],
                                               [UIImage imageNamed:@"CB00018"],
                                               [UIImage imageNamed:@"CB00019"],
                                               [UIImage imageNamed:@"CB00020"],
                                               [UIImage imageNamed:@"CB00021"],
                                               [UIImage imageNamed:@"CB00022"],
                                               [UIImage imageNamed:@"CB00023"],
                                               [UIImage imageNamed:@"CB00024"],
                                               [UIImage imageNamed:@"CB00025"],
                                               [UIImage imageNamed:@"CB00026"],
                                               [UIImage imageNamed:@"CB00027"],
                                               [UIImage imageNamed:@"CB00028"],
                                               [UIImage imageNamed:@"CB00029"],
                                               [UIImage imageNamed:@"CB00030"],
                                               [UIImage imageNamed:@"CB00031"],
                                               [UIImage imageNamed:@"CB00032"],
                                               [UIImage imageNamed:@"CB00033"],
                                               [UIImage imageNamed:@"CB00034"],
                                               [UIImage imageNamed:@"CB00035"],
                                               [UIImage imageNamed:@"CB00036"],
                                               [UIImage imageNamed:@"CB00037"],
                                               [UIImage imageNamed:@"CB00038"],
                                               [UIImage imageNamed:@"CB00039"],
                                               [UIImage imageNamed:@"CB00040"],
                                               [UIImage imageNamed:@"CB00041"],
                                               [UIImage imageNamed:@"CB00042"],
                                               [UIImage imageNamed:@"CB00043"],
                                               [UIImage imageNamed:@"CB00044"],
                                               [UIImage imageNamed:@"CB00045"],
                                               [UIImage imageNamed:@"CB00046"],
                                               [UIImage imageNamed:@"CB00047"],
                                               [UIImage imageNamed:@"CB00048"],
                                               [UIImage imageNamed:@"CB00049"],
                                               [UIImage imageNamed:@"CB00050"],
                                               [UIImage imageNamed:@"CB00051"],
                                               [UIImage imageNamed:@"CB00052"],
                                               [UIImage imageNamed:@"CB00053"],
                                               [UIImage imageNamed:@"CB00054"],
                                               [UIImage imageNamed:@"CB00055"],
                                               [UIImage imageNamed:@"CB00056"],
                                               [UIImage imageNamed:@"CB00057"],
                                               [UIImage imageNamed:@"CB00058"],
                                               [UIImage imageNamed:@"CB00059"],
                                               [UIImage imageNamed:@"CB00060"], nil];

    self.backgroundImageView.animationDuration = 2.5f;
    self.backgroundImageView.animationDuration = 1;


- (void)didReceiveMemoryWarning
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.

#pragma mark - Prediction

- (void) makePredictions {
    [self.backgroundImageView startAnimating];
    self.predictionLabel.text = [self.crystalBall randomPredictions];


#pragma mark - Motion Events

-(void) motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event {
    self.predictionLabel.text = nil;

-(void) motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event {
    if (motion == UIEventSubtypeMotionShake) {
        [self makePredictions];


-(void) motionCancelled:(UIEventSubtype)motion withEvent:(UIEvent *)event {


#pragma mark - Touch Events

-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    self.predictionLabel.text = nil;
-(void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
    [self makePredictions];
-(void) touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {



1 Answer

Stone Preston
Stone Preston
42,016 Points

below is your code:

// you set the same property twice
self.backgroundImageView.animationDuration = 2.5f;
self.backgroundImageView.animationDuration = 1;

you set the animation duration twice. you need to set the animationDuration to 2.5 and then the animationRepeatCount to 1

self.backgroundImageView.animationDuration = 2.5f;
self.backgroundImageView.animationRepeatCount = 1;

according to the documentation on the animationRepeatCount property of UIImageView:

The default value is 0, which specifies to repeat the animation indefinitely.

which explains why you were getting an infinite loop. you never set the value and it defaults to 0, so it looped infinitely.