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iOS

Posted by J.R. Sedivy
J.R. Sedivy
2,545 Points

Readonly Attribute Errors In First Build

I am approximately 3:50 into the Readonly Attribute tutorial and am stuck after running the application. I receive two compiler errors for my CrystalBall.m file:

  1. Method definition for 'randomPrediction' not found.
  2. Use of undeclared identifier 'randomPrediction'

Here is the code for my CrystalBall.m file:

   #import "LKCrystalBall.h"

   @implementation LKCrystalBall

   - (NSArray *) predictions {
       if (_predictions == nil){
           _predictions = [[NSArray alloc] initWithObjects:@"It is Certain",@"It is Decidedly so",@"All signs say YES",
           @"The stars are not aligned",
           @"My reply is no",
           @"It is doubtful",
           @"Better not tell you now",
           @"Concentrate and ask again",
           @"Unable to answer now", nil];
       }
       return _predictions;

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

1 Answer

J.R. Sedivy
J.R. Sedivy
2,545 Points
J.R. Sedivy
J.R. Sedivy
2,545 Points

Never mind, figured it out. Looks like I had a curly brace misplaced. Program not compiles and runs correctly. Here is the updated code: 

#import "LKCrystalBall.h"

@implementation LKCrystalBall

- (NSArray *) predictions {
    if (_predictions == nil){
        _predictions = [[NSArray alloc] initWithObjects:@"It is Certain",@"It is Decidedly so",@"All signs say YES",
        @"The stars are not aligned",
        @"My reply is no",
        @"It is doubtful",
        @"Better not tell you now",
        @"Concentrate and ask again",
        @"Unable to answer now", nil];
    }
    return _predictions;
}

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

@end