自定义类的对象没有获取存储在NSMutableArray

Question

我想将对象添加到NSMutableArray但编写以下代码后，我得到benchmarkArray NIL。哪里出错帮我请

[benchmark setBenchmarkTitle:self.benchmarkTitle.text]; 
    [benchmark setBenchmarkDescription:self.benchmarkDescription.text]; 
    [benchmarkArray addObject:benchmark]; 

我的Benchmark类是：

@interface Benchmark : NSObject 

@property (nonatomic, retain) NSString *bid; 
@property (nonatomic, retain) NSString *benchmarkTitle; 
@property (nonatomic, retain) NSString *benchmarkDescription; 

-(id)initWithCoder: (NSCoder *)coder; 
-(void)encodeWithCoder:(NSCoder *)encoder; 

@end 

@implementation Benchmark 

@synthesize bid; 
@synthesize benchmarkTitle; 
@synthesize benchmarkDescription; 

- (id) initWithCoder:(NSCoder *)coder { 

    self = [super init]; 
    if(self) { 
     bid = [coder decodeObjectForKey:@"id"]; 
     benchmarkTitle = [coder decodeObjectForKey:@"benchmarkTitle"]; 
     benchmarkDescription = [coder decodeObjectForKey:@"benchmarkDescription"]; 
    } 
    return self; 
} 

- (void) encodeWithCoder:(NSCoder *)encoder { 

    [encoder encodeObject:bid forKey:@"id"]; 
    [encoder encodeObject:benchmarkTitle forKey:@"benchmarkTitle"]; 
    [encoder encodeObject:benchmarkDescription forKey:@"benchmarkDescription"]; 
} 

@end 

Answer 1

你忘了分配和初始化

benchmarkArray = [[NSMutableArray alloc] init]; 

Answer 2

没有错，你的Benchmark类。

您的问题在于您创建的课程benchMarkArray。

使得它的属性后，您需要初始化它init/awakeFromNib/viewDidLoad方法：

benchMarkArray=[[NSArray alloc]init]; 

，或者

benchmarkArray=[NSArray new];