设置NSInteger属性时接收器类型“NSInteger”无效

        self.price = p; // this line throws error

我应该指定价格吗 copy ? 更多详细信息:

@interface SafeItem : NSObject {
    NSString *name;
    NSInteger price;
    NSString *category;
    NSInteger itemid;
    BOOL hasImage;
}

@property (nonatomic,copy) NSString *name;
@property (nonatomic) NSInteger price;
@property (nonatomic,copy) NSString *category;
@property NSInteger itemid;
@property BOOL hasImage;

- (id)initWithName:(NSString*) n price:(NSInteger) p category:(NSString*) c; 

@end

实施:

@implementation SafeItem

@synthesize name, price, category, itemid, hasImage;

- (id)initWithName:(NSString*) n price:(NSInteger) p category:(NSString*) c {
    if(self=[super init]){
        self.itemid = [SafeItem getNextId];
        self.name = [n copy];
        self.price = p; // this line throws error
        self.category = [c copy];
    }
    return self;
}