objective-c - 继承的属性不起作用

Question

我在 objective-c 中无法实现某些功能。我有以下协议(protocol):

@protocol PFItem <NSObject>

- (NSNumber *)weight;
- (NSNumber *)cost;

@end

该协议(protocol)在以下类中实现:

@interface PFItemObject : NSObject <NSCoding, PFItem> {
    NSString *name;
    NSNumber *weight;
    NSNumber *cost;
}

@property (retain, nonatomic) NSString *name;
@property (retain, nonatomic) NSNumber *weight;
@property (retain, nonatomic) NSNumber *cost;
@property (readonly) NSString *className;

+ (id)itemWithString:(NSString *)string;

@end

现在，这对我来说效果很好，除非我像这样使用 PFItemObject 作为父类(super class):

@interface PFWeaponObject : PFItemObject <NSCoding, PFItem> {
    NSString *damage;
    NSString *critical;
    NSString *range;
    NSNumber *attackBonus;
    NSNumber *damageBonus;
    WeaponTypes type;
    BOOL isTwoHanded;
}

@property (retain, nonatomic) NSString *damage;
@property (retain, nonatomic) NSString *critical;
@property (retain, nonatomic) NSString *range;
@property (retain, nonatomic) NSNumber *attackBonus;
@property (retain, nonatomic) NSNumber *damageBonus;
@property WeaponTypes type;
@property BOOL isTwoHanded;

+ (PFWeaponObject *)unarmedWeapon;

@end

PFWeaponObject 中的 +itemWithString: 方法的工作原理如下:

+ (id)itemWithString:(NSString *)string {
    NSArray *components = [string componentsSeparatedByString:@";"];
    PFWeaponObject *weapon = [[PFWeaponObject alloc] init];

    [weapon setName:[components objectAtIndex:0]];
    [weapon setWeight:[NSNumber numberWithFloat:[[components objectAtIndex:1] floatValue]]];
    [weapon setCost:[NSNumber numberWithInt:[[components objectAtIndex:2] intValue]]];
    [weapon setDamage:[components objectAtIndex:3]];
    [weapon setCritical:[components objectAtIndex:4]];
    [weapon setRange:[components objectAtIndex:5]];
    [weapon setType:[[components objectAtIndex:6] integerValue]];
    [weapon setAttackBonus:[NSNumber numberWithInt:[[components objectAtIndex:7] intValue]]];
    [weapon setDamageBonus:[NSNumber numberWithInt:[[components objectAtIndex:8] intValue]]];
    [weapon setIsTwoHanded:[[components objectAtIndex:9] boolValue]];

    return [weapon autorelease];  
}

我认为，因为我是从 PFItemObject 继承的，所以我应该能够毫无问题地为父类(super class)的属性赋值。但是当我执行以下操作时:

- (void)testItemCreationStrings {
    NSString *weaponString = @"+1 Greatsword;25;2500;2d6;x3;Melee;5;1;1;YES";
    PFWeaponObject *sampleWeapon = [PFWeaponObject itemWithString:weaponString];
}

父类(super class) (PFItemObject) 中的所有属性均返回 @"+1 Greatsword"。我是否错过了一些我应该做的事情？

感谢您提供的任何帮助，如果需要，请随时询问更多信息。

Answer 1

编辑，因为问题已被编辑。我想我有一个解决方案。

试试这个:

+ (id)itemWithString:(NSString *)string {
    NSArray *components = [string componentsSeparatedByString:@";"];
    PFWeaponObject *weapon = [[PFWeaponObject alloc] init];

    [weapon setName:[components objectAtIndex:0]];
    [weapon setWeight:[NSNumber numberWithInt:[[components objectAtIndex:1] intValue]]];
    [weapon setCost:[NSNumber numberWithInt:[[components objectAtIndex:2] intValue]]];
    // etc.
    // etc.
}

我认为您没有设置 NSNumberFormatter 的行为和格式，而且我也认为使用它是没有必要的。如果您出于某种原因确实想这样做，还有其他如何使用数字格式化程序的示例。如果您出于某种原因想要/需要，我可以提供指导。