RESTkit 无法识别的选择器错误

Question

我正在尝试通过 iPhone 将人员类别添加到我的服务器。

我有以下代码，但收到此错误：

* 由于未捕获的异常“NSInvalidArgumentException”而终止应用程序，原因：“+[Person 对象]：无法识别的选择器发送到类 0x5fe6c”错误

@interface Data : NSObject {
Person *person;
NSArray *dogs;
}
@property (nonatomic ,retain) Person *person;
@property (nonatomic ,retain) NSArray *dogs;
@end

@interface Person : NSObject {

NSString *name;
NSNumber *personId;
NSDate   *updatedAt;
NSDate   *createdAt;

}

@property (nonatomic , retain) NSDate * createdAt;
@property (nonatomic , retain) NSDate * updatedAt;
@property (nonatomic , retain) NSNumber  *personId;
@property (nonatomic , retain) NSString *name;
@end

RKObjectMapping* userMapping = [RKObjectMapping mappingForClass:[Person class]];

[userMapping mapKeyPath:@"created_at" toAttribute:@"createdAt"];
[userMapping mapKeyPath:@"updated_at" toAttribute:@"updatedAt"];
[userMapping mapKeyPath:@"name" toAttribute:@"name"]; 
[userMapping mapKeyPath:@"id" toAttribute:@"personId"];

RKObjectMapping* dogMapping = [RKObjectMapping mappingForClass:[Dog class]];
[dogMapping mapKeyPath:@"created_at" toAttribute:@"createdAt"]; 
[dogMapping mapKeyPath:@"person_id" toAttribute:@"spersonId"]; 
[dogMapping mapKeyPath:@"name" toAttribute:@"name"]; 
[dogMapping mapKeyPath:@"updated_at" toAttribute:@"updatedAt"]; 
[dogMapping mapKeyPath:@"id" toAttribute:@"dogId"]; 

RKObjectMapping *dataMapping = [RKObjectMapping mappingForClass:[Data class]]; 
[dataMapping mapKeyPath:@"dog" toAttribute:@"dogs"]; 
[dataMapping mapKeyPath:@"person" toRelationship:@"person" withMapping:userMapping]; 
[[RKObjectManager sharedManager].mappingProvider addObjectMapping:dataMapping]; 

[[RKObjectManager sharedManager] loadObjectsAtResourcePath:@"/people"       
objectMapping:dataMapping delegate:self]; 


-(void)createObject{

RKObjectRouter * router = [RKObjectManager sharedManager].router;
[router routeClass: [Person class] toResourcePath:@"/people/:personId"];
[router routeClass: [Person class] toResourcePath:@"/people"          
forMethod:RKRequestMethodPOST];
Data *data =[[Data alloc]init];
Person *daveLiu = [Person object];
daveLiu.name = @"Dave Liu";
[[RKObjectManager sharedManager] postObject:daveLiu delegate:self];
}

Answer 1

让我们来分解一下：

由于未捕获的异常“NSInvalidArgumentException”而终止应用

好的，您有一个无效的参数异常。为什么？

原因：'+[Person 对象]：

在 Person 类上调用了名为 object 的类方法

无法识别的选择器发送到类 0x5fe6c' 错误

...但 Person 类没有实现 object 类方法。查看您的 Person 实现，我们可以看到情况就是如此。

那么，我们从哪里调用它呢？快速浏览 mja 的评论，代码向我们显示了这一行：

Person *daveLiu = [Person object];

这可能是你的罪魁祸首。正如 mja 所说，这可能应该是

Person *daveLiu = [Person alloc] init];