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iOS Build a Simple iPhone App (iOS7) Animating and Intercepting Events Intercepting Touch Events

Posted by Aurelien Schlumberger
Aurelien Schlumberger
6,127 Points

makePrediction method crashes my crystalBall app

I added the methods as explained in the video but my crystalBall crashes when I touch or shake the devices.

Is there a problem with my code?

AUDViewController.h:
...
- (void) makePrediction;

AUDViewController.m:
...
#pragma mark - Prediction
- (void) makePrediction {
    self.predictionLabel.text = [self.crystalBall randomPredictions];
    self.predictionLabel.textColor = [self.crystalBall randomColors];
}

...

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

...

- (void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
    [self makePrediction];
}

1 Answer

Aurelien Schlumberger
Aurelien Schlumberger
6,127 Points

Well I figured it out and it was unrelated to the method makePrediction. It was crashing because I made a mistake when commenting out older code that I wanted to preserve

Bad comments:

// Removed because instead of using the button predict the random string, we use the touch screen event.
// - (IBAction)buttonPressed {
//    self.predictionLabel.text = [self.crystalBall randomPrediction];
//    self.predictionLabel.textColor = [self.crystalBall randomColor];
// }

Correct comments

// Removed because instead of using the button predict the random string, we use the touch screen event.
//- (IBAction)buttonPressed {
//   self.predictionLabel.text = [self.crystalBall randomPrediction];
//   self.predictionLabel.textColor = [self.crystalBall randomColor];
//}

I learn cool hotkey command to comment out chunks of code by pressing "command" + "/"