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Crystal Ball stopAnimating

Wondering if anyone else experienced the background animating on every other event?

I ended up adding [self.backgroundImage stopAnimating] in my motionBegan withEvent function to fix this.

Is there a better way?

// Deliver a prediction
- (void)makePrediction {
    [self.backgroundImage startAnimating];
    NSUInteger randomIndex = arc4random_uniform([self.predictionArray count]);
    self.predictionLabel.text = [predictionArray objectAtIndex:randomIndex];

- (void)resetPredictionLabel {
    self.predictionLabel.text = @"Ask a question";

// Clear the current prediction
- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event {
    predictionLabel.text = @"";
    [self.backgroundImage stopAnimating];

// Display new prediction
- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event {
    if(motion == UIEventSubtypeMotionShake) {
        [self makePrediction];

1 Answer

Amit Bijlani
Amit Bijlani
Treehouse Guest Teacher

That should not happen since you are starting the animation in the makePrediction method.

That was my assumption. However, in the simulator (I haven't tested on a device), the animation only fired on every other shake. Could this be a product of the simulator?

I will inspect my code further for something I may have missed, also.