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[英]Failed to call designated initializer on NSManagedObject class ’XYX’ with RestKit-0.20.3
[英]Restkit-Failed to call designated initializer on NSManagedObject class
我將Restkit用於擴展NSManagedObject的類。 我知道rest kit本身具有從網絡獲取保存到核心數據的功能。 但是,由於以下原因,我無法使用該功能:
所以我想做的是讓我的Model類擴展nsmanaged對象,並在需要時保存它。 但是我得到這個錯誤:
CoreData:錯誤:無法在NSManagedObject類上調用指定的初始化程序
有辦法解決這個問題嗎?
我從服務器這樣獲取:
@implementation API_Login
+(void)performLoginWithEmail:(NSString*)email
withPassword:(NSString*)password
success:(void (^)(Token* user) )success
failure:failureblock failure{
RKObjectManager * objectManager = [APIHelper getRestObjectManager];
RKObjectMapping *tokenMapping = [RKObjectMapping mappingForClass:[Token class]];
//add mapping for token
[tokenMapping addPropertyMapping:[RKAttributeMapping attributeMappingFromKeyPath:nil toKeyPath:@"token"]];
RKResponseDescriptor *responseDescriptor =
[RKResponseDescriptor responseDescriptorWithMapping:tokenMapping
method:RKRequestMethodGET
pathPattern:nil
keyPath:nil
statusCodes:[NSIndexSet indexSetWithIndex:200]];
[objectManager addResponseDescriptor:responseDescriptor];
// add mapping for error
RKObjectMapping *errorMapping = [RKObjectMapping mappingForClass:[Error class]];
[errorMapping addAttributeMappingsFromDictionary:@{@"message":@"message",@"badRequest":@"badRequest"}];
RKResponseDescriptor *errorResponseDescriptor =
[RKResponseDescriptor responseDescriptorWithMapping:errorMapping
method:RKRequestMethodGET
pathPattern:nil
keyPath:nil
statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassClientError)];
[objectManager addResponseDescriptor:errorResponseDescriptor];
NSDictionary *queryParams = @{@"email" : email,
@"password" : password,
};
[objectManager postObject:nil
path:@"/users/api/login"
parameters:queryParams
success:^(RKObjectRequestOperation *operation, RKMappingResult *mappingResult) {
Token* token = (Token*)[mappingResult firstObject] ;
// [AppDelegateHandle setToken:token];
success(token);
} failure:^(RKObjectRequestOperation *operation, NSError *error) {
NSArray* e = [[error userInfo] objectForKey:RKObjectMapperErrorObjectsKey];
Error *err = (Error*)[e objectAtIndex:0];
NSLog(@"%@",[err.badRequest allValues] );
failure(operation,error);
}];
}
@end
我的令牌類如下所示:
@interface Token : NSManagedObject
@property NSString* token;
@end
和我的api響應看起來像:
{
"token": "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdWIiOjEsImlzcyI6Imh0dHA6XC9cL3JlbWluZGVyLmRldlwvdXNlcnNcL2FwaVwvbG9naW4iLCJpYXQiOjE0Njg1OTM3NjYsImV4cCI6MTQ2OTE5Mzc2NiwibmJmIjoxNDY4NTkzNzY2LCJqdGkiOiIxMDc3ZjBhY2ViYTFjOWZjZWNhYjkyMzYyOTA0ZmI4NSJ9.I6FHJLCCHr3EHQa8HgaDqxQMjF1HVyA5AymPjvBGDrM"
}
當我更改令牌以擴展NSObject而不是NSManagedObject時,一切正常。 可能是什么問題?
發生這種情況是因為您使用的是RKObjectMapping
而不是RKEntityMapping
,如果您使用的是NSManagedObject
的子類, NSManagedObject
。
如果您不打算將其直接添加到上下文中, NSManagedObject
不能使用NSManagedObject
的子類。
如果您的請求僅包含一個令牌,那么我可能不會理會RestKit,但在一般情況下,我會使用與您的托管對象類相同的鍵將其映射到NSDictionary
,然后在您要創建托管對象時可以這樣做,並使用setValuesForKeysWithDictionary:
將數據“導入”到他們。
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