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Eric Hurst
1,017 PointsCrystal 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
Treehouse Guest TeacherThat should not happen since you are starting the animation in the makePrediction
method.
Eric Hurst
1,017 PointsEric Hurst
1,017 PointsThat 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.
Thanks.