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iOS

Posted by Daniel Davies
Daniel Davies
2,105 Points

CrystalBall Warning when running on device.

Hey,

Finished the Crystal Ball app and when running it in the simulator no errors or warnings or anything - perfect.

When I run it on my iPhone Xcode throws out a warning. The app runs fine but the warning pops up.

The warning I'm getting is on the GWSCrystallBall.m where I call

  • (NSString*) randomPrediction { int random = arc4random_uniform(self.predictions.count); return [self.predictions objectAtIndex:random]; }

The warning is:

Implicit conversion loses integer precision 'NSUInteger' (aka 'unassigned long') to 'uint_32_t' (aka 'unassigned int')

Not sure if there is any more to that warning as the screen crops it.

Any assistance would be appreciated.

3 Answers

Micah Elias
Micah Elias
2,774 Points
Micah Elias
Micah Elias
2,774 Points

Change the randomPrediction method to look like this:

- (NSString*) randomPrediction;
{
    int random = arc4random_uniform((unsigned int)self.predictions.count);
    return [self.predictions objectAtIndex:random];
}
Daniel Davies
Daniel Davies
2,105 Points
Daniel Davies
Daniel Davies
2,105 Points

Hey thanks, this works and removed the warning. Any ideas why this isn't provided on the videos?

Chris Shepherd
Chris Shepherd
4,374 Points
Chris Shepherd
Chris Shepherd
4,374 Points

Worked! Thanks Micah Elias, a quick explaination of why (unsigned int) needed to be added would be awesome :)

Update: So I had my iPhone Simulator on 4-inch 64-bit. I changed it back to 3.5-inch and the build worked without the (unsigned int).