沒有錯誤，但NSLog不輸出

Question

我忙於在Xcode中做測試程序。到目前爲止，我在main.m中有這個代碼。我根本沒有得到任何錯誤，但輸出沒有發生，例如打印方法中的NSLog。

可能是什麼問題？我知道我必須失去一些明顯的東西。

#import <UIKit/UIKit.h> 

#import "JTAppDelegate.h" 


@interface Fraction: NSObject 

-(void) print; 
-(void) setNumerator: (int) n; 
-(void) setDenominator: (int) d; 

@end 

@implementation Fraction 

{ 
    int numerator; 
    int denominator; 
} 

-(void) print 
{ 
     NSLog (@"%i/%i", numerator, denominator); 
} 

-(void) setNumerator:(int)n 
{ 
    numerator = n; 
} 

-(void) setDenominator:(int)d 
{ 
    denominator = d; 
} 

@end 

int main (int argc, char * argv[]) 
{ 
    @autoreleasepool { 

     return UIApplicationMain(argc, argv, nil, NSStringFromClass([JTAppDelegate class])); 


     // Create an instance of Fraction and initialise it 

     Fraction *myFraction = [[Fraction alloc] init]; 

     //Set Fraction to 1/3 

     [myFraction setNumerator: 1]; 
     [myFraction setDenominator: 3]; 

     //Display the fraction using the print method 

     [myFraction print]; 
    } 


} 

Answer 1

您print是return後，從未達到這個代碼。

Answer 2

寫打印和上面的所有代碼返回語句。

Answer 3

替換此： -

int main (int argc, char * argv[]) 
{ 
    @autoreleasepool { 



     // Create an instance of Fraction and initialise it 

     Fraction *myFraction = [[Fraction alloc] init]; 

     //Set Fraction to 1/3 

     [myFraction setNumerator: 1]; 
     [myFraction setDenominator: 3]; 

     //Display the fraction using the print method 

     [myFraction print]; 

     return UIApplicationMain(argc, argv, nil, NSStringFromClass([JTAppDelegate class])); 

    } 


}