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Xcode 8.1 IOS10.1 CoreData delete不会真正删除_Ios_Objective C_Core Data - Fatal编程技术网

Xcode 8.1 IOS10.1 CoreData delete不会真正删除

Xcode 8.1 IOS10.1 CoreData delete不会真正删除,ios,objective-c,core-data,Ios,Objective C,Core Data,我在使用iOS核心数据时遇到了一种非常奇怪的行为,我从web服务下载项目并使用核心数据将其存储在本地,我有一个UTTableViewController,显示本地实体中存储的内容,同一个tableController还允许对所选项目执行删除操作。 我对属性“itemId”也有一个约束以避免重复,如果itemId是重复的,我使用默认行为抛出一个错误 问题如下 当我第一次从webservice下载项目时,它完全按照预期工作 如果我尝试重新加载数据,约束将正确显示存在冲突的错误 然后我进入UITabl

我在使用iOS核心数据时遇到了一种非常奇怪的行为,我从web服务下载项目并使用核心数据将其存储在本地,我有一个UTTableViewController,显示本地实体中存储的内容,同一个tableController还允许对所选项目执行删除操作。 我对属性“itemId”也有一个约束以避免重复,如果itemId是重复的,我使用默认行为抛出一个错误

问题如下

当我第一次从webservice下载项目时,它完全按照预期工作

如果我尝试重新加载数据,约束将正确显示存在冲突的错误

然后我进入UITableViewController并删除其中一个项目,这与预期的一样,ViewCOntroller会显示其余的项目

现在我从web服务重新加载项目,现在它无法添加回已删除的项目,约束告诉我存在冲突

这就好像该项目没有真正删除,仍然挂在背景中,但不可见

调试告诉我,一切看起来都很好

有人能帮我解释一下,当我重新加载删除的同一个itemId时,为什么会出现约束错误

这是下载方法

+ (void)fetchTillData:(int)tillId; {

if ([NWTillHelper isDebug] == 1) {
    NSLog(@"WebServices:fetchTillData:tillId = %d", tillId);
}

NSString *finalURL = [NSString stringWithFormat:@"https://foo.bar.com:5443/api/till/tilldata/%d?StartAtRow=0&TakeNoOfRows=10",tillId];

[[[NSURLSession sharedSession] dataTaskWithURL:[NSURL URLWithString:finalURL]
                             completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {

                                 if (error != nil) {
                                     if ([NWTillHelper isDebug] == 1) {
                                         NSLog(@"WebServices:fetchTillData:Transport error %@", error);
                                     }
                                 } else {
                                     NSHTTPURLResponse *responseHTTP;
                                     responseHTTP = (NSHTTPURLResponse *) response;

                                     if(responseHTTP.statusCode != 200) {
                                         if ([NWTillHelper isDebug] == 1) {
                                             NSLog(@"WebServices:fetchTillData:Server Error %d", (int) responseHTTP.statusCode);
                                         }
                                     } else {
                                         NSArray *tillBasicDataArray = [NSJSONSerialization JSONObjectWithData:data
                                                                                                       options:0
                                                                                                         error:NULL];
                                         if ([NWTillHelper isDebug] == 1) {
                                             NSLog(@"WebServices:fetchTillData:tillBasicDataArray count = %lu", (unsigned long)[tillBasicDataArray count]);
                                             NSLog(@"WebServices:fetchTillData:tillBasicDataArray looks like %@",tillBasicDataArray);
                                         }

                                         NSDictionary *tillBasicDataDict = Nil;

                                         //Loop through the array and for each dictionary insert into local DB
                                         for (id element in tillBasicDataArray){
                                             tillBasicDataDict = element;

                                             NSString *itemId = [tillBasicDataDict objectForKey:@"itemId"];
                                             NSString *companyId = [tillBasicDataDict objectForKey:@"companyId"];
                                             NSString *languageId = [tillBasicDataDict objectForKey:@"languageCode"];
                                             NSString *colorCode = [tillBasicDataDict objectForKey:@"colorCode"];
                                             NSString *discountable = [tillBasicDataDict objectForKey:@"discountable"];
                                             NSString *exchangeable = [tillBasicDataDict objectForKey:@"exchangeable"];
                                             NSString *noos14 = [tillBasicDataDict objectForKey:@"noos14"];
                                             NSString *sizeCode = [tillBasicDataDict objectForKey:@"sizeCode"];
                                             NSString *taxGroup = [tillBasicDataDict objectForKey:@"taxGroupId"];
                                             NSString *taxRegion = [tillBasicDataDict objectForKey:@"taxRegion"];
                                             NSString *tradeItemDesc = [tillBasicDataDict objectForKey:@"tradeItemDesc"];
                                             NSString *withTax = [tillBasicDataDict objectForKey:@"withTax"];
                                             NSString *status = [tillBasicDataDict objectForKey:@"status"];

                                             // Use Core Data FMD
                                             AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication]delegate];

                                             //AppDelegate *appDelegate =
                                             //[[UIApplication sharedApplication] delegate];

                                             NSManagedObjectContext *context =
                                             appDelegate.persistentContainer.viewContext;
                                             NSManagedObject *newPimItem = Nil;
                                             newPimItem = [NSEntityDescription
                                                            insertNewObjectForEntityForName:@"TillData"
                                                            inManagedObjectContext:context];

                                             [newPimItem setValue:itemId forKey:@"itemId"];
                                             [newPimItem setValue:companyId forKey:@"companyId"];
                                             [newPimItem setValue:languageId forKey:@"languageCode"];
                                             [newPimItem setValue:colorCode forKey:@"colorCode"];
                                             [newPimItem setValue:discountable forKey:@"discountable"];
                                             [newPimItem setValue:exchangeable forKey:@"exchangeable"];
                                             [newPimItem setValue:noos14 forKey:@"noos14"];
                                             [newPimItem setValue:sizeCode forKey:@"sizeCode"];
                                             [newPimItem setValue:[NSNumber numberWithInt:[taxGroup intValue]] forKey:@"taxGroup"];
                                             [newPimItem setValue:taxRegion forKey:@"taxRegion"];
                                             [newPimItem setValue:tradeItemDesc forKey:@"tradeItemDesc"];
                                             [newPimItem setValue:[NSNumber numberWithInt:[withTax intValue]] forKey:@"withTax"];
                                             [newPimItem setValue:[NSNumber numberWithInt:[status intValue]] forKey:@"status"];

                                             NSError *error = Nil;
                                             [context save:&error];

                                             if ([NWTillHelper isDebug] == 1) {
                                                 NSLog(@"WebServices:fetchTillData:ItemId in loop = %@", itemId);
                                                 NSLog(@"WebServices:fetchTillData:newPimItem = %@", newPimItem);
                                                 NSLog(@"WebServices:fetchTillData:CoreData error = %@", error);
                                             }

                                             if(error != nil) {
                                                 // Do something here
                                             } else {
                                                 NSUserDefaults *tillUserDefaults = [NSUserDefaults standardUserDefaults];
                                                 [tillUserDefaults setInteger:1 forKey:@"hasTillData"];
                                                 [tillUserDefaults synchronize];
                                             }
                                         }
                                     }
                                 }
                             }] resume];
}
调试告诉我,我在任何地方都没有任何NIL/NULL值

调试还向我显示,每个变量都保存着期望值

下面是使用NSLog从webservice获得的JSON数组,所有值都是正确的

WebServices:fetchTillData:tillBasicDataArray looks like (
    {
    colorCode = 95;
    companyId = "BE_HM";
    discountable = 1;
    exchangeable = 1;
    itemId = 101064025138010;
    languageCode = eng;
    noos14 = "09258384374953,09258387354952";
    sizeCode = "163-010";
    status = 1;
    taxGroupId = 1;
    taxRegion = BE;
    tradeItemDesc = "Jersey basic";
    withTax = 1;
},
    {
    colorCode = 95;
    companyId = "BE_HM";
    discountable = 1;
    exchangeable = 1;
    itemId = 101064025138011;
    languageCode = eng;
    noos14 = "09258384394951,09258387434951";
    sizeCode = "163-011";
    status = 1;
    taxGroupId = 1;
    taxRegion = BE;
    tradeItemDesc = "Jersey basic";
    withTax = 1;
},
    {
    colorCode = 95;
    companyId = "BE_HM";
    discountable = 1;
    exchangeable = 1;
    itemId = 101064025138012;
    languageCode = eng;
    noos14 = "09258385254957,09258389874953";
    sizeCode = "163-012";
    status = 1;
    taxGroupId = 1;
    taxRegion = BE;
    tradeItemDesc = "Jersey basic";
    withTax = 1;
}
)
但是,即使删除了所有条目并且tableViewController显示我的数据库为空,我仍然会收到此错误

    2016-11-23 15:07:36.714 NWMobileTill[674:9231] WebServices:fetchTillData:ItemId in loop = 101064025138010
2016-11-23 15:07:36.715 NWMobileTill[674:9231] WebServices:fetchTillData:newPimItem = <TillData: 0x6000002ce9a0> (entity: TillData; id: 0x600000624620 <x-coredata:///TillData/t7807C999-528C-4616-A012-592A3D77D28D15> ; data: {
    colorCode = 95;
    companyId = "BE_HM";
    discountable = 1;
    exchangeable = 1;
    itemId = 101064025138010;
    languageCode = eng;
    noos14 = "09258384374953,09258387354952";
    sizeCode = "163-010";
    status = 1;
    taxGroup = 1;
    taxRegion = BE;
    tradeItemDesc = "Jersey basic";
    withTax = 1;
})
2016-11-23 15:07:36.717 NWMobileTill[674:9231] WebServices:fetchTillData:CoreData error = Error Domain=NSCocoaErrorDomain Code=133021 "(null)" UserInfo={conflictList=(
    "NSConstraintConflict (0x60000086dcc0) for constraint (\n    itemId\n): database: (null), conflictedObjects: (\n    \"<TillData: 0x6000000de4c0> (entity: TillData; id: 0x600000435500 <x-coredata:///TillData/t7807C999-528C-4616-A012-592A3D77D28D7> ; data: {\\n    colorCode = 95;\\n    companyId = \\\"BE_HM\\\";\\n    discountable = 1;\\n    exchangeable = 1;\\n    itemId = 101064025138012;\\n    languageCode = eng;\\n    noos14 = \\\"09258385254957,09258389874953\\\";\\n    sizeCode = \\\"163-012\\\";\\n    status = 1;\\n    taxGroup = 1;\\n    taxRegion = BE;\\n    tradeItemDesc = \\\"Jersey basic\\\";\\n    withTax = 1;\\n})\",\n    \"<TillData: 0x6000002ce3f0> (entity: TillData; id: 0x60000023bda0 <x-coredata:///TillData/t7807C999-528C-4616-A012-592A3D77D28D13> ; data: {\\n    colorCode = 95;\\n    companyId = \\\"BE_HM\\\";\\n    discountable = 1;\\n    exchangeable = 1;\\n    itemId = 101064025138012;\\n    languageCode = eng;\\n    noos14 = \\\"09258385254957,09258389874953\\\";\\n    sizeCode = \\\"163-012\\\";\\n    status = 1;\\n    taxGroup = 1;\\n    taxRegion = BE;\\n    tradeItemDesc = \\\"Jersey basic\\\";\\n    withTax = 1;\\n})\",\n    \"<TillData: 0x6080002cfc00> (entity: TillData; id: 0x60800022f920 <x-coredata:///TillData/t7807C999-528C-4616-A012-592A3D77D28D4> ; data: {\\n    colorCode = 95;\\n    companyId = \\\"BE_HM\\\";\\n    discountable = 1;\\n    exchangeable = 1;\\n    itemId = 101064025138012;\\n    languageCode = eng;\\n    noos14 = \\\"09258385254957,09258389874953\\\";\\n    sizeCode = \\\"163-012\\\";\\n    status = 1;\\n    taxGroup = 1;\\n    taxRegion = BE;\\n    tradeItemDesc = \\\"Jersey basic\\\";\\n    withTax = 1;\\n})\"\n)",
    "NSConstraintConflict (0x60000067fd40) for constraint (\n    itemId\n): database: (null), conflictedObjects: (\n    \"<TillData: 0x6080002d0760> (entity: TillData; id: 0x608000233320 <x-coredata:///TillData/t7807C999-528C-4616-A012-592A3D77D28D6> ; data: {\\n    colorCode = 95;\\n    companyId = \\\"BE_HM\\\";\\n    discountable = 1;\\n    exchangeable = 1;\\n    itemId = 101064025138011;\\n    languageCode = eng;\\n    noos14 = \\\"09258384394951,09258387434951\\\";\\n    sizeCode = \\\"163-011\\\";\\n    status = 1;\\n    taxGroup = 1;\\n    taxRegion = BE;\\n    tradeItemDesc = \\\"Jersey basic\\\";\\n    withTax = 1;\\n})\",\n    \"<TillData: 0x6080002cfb20> (entity: TillData; id: 0x60800022f9e0 <x-coredata:///TillData/t7807C999-528C-4616-A012-592A3D77D28D3> ; data: {\\n    colorCode = 95;\\n    companyId = \\\"BE_HM\\\";\\n    discountable = 1;\\n    exchangeable = 1;\\n    itemId = 101064025138011;\\n    languageCode = eng;\\n    noos14 = \\\"09258384394951,09258387434951\\\";\\n    sizeCode = \\\"163-011\\\";\\n    status = 1;\\n    taxGroup = 1;\\n    taxRegion = BE;\\n    tradeItemDesc = \\\"Jersey basic\\\";\\n    withTax = 1;\\n})\",\n    \"<TillData: 0x6080002d3be0> (entity: TillData; id: 0x608000221ea0 <x-coredata:///TillData/t7807C999-528C-4616-A012-592A3D77D28D12> ; data: {\\n    colorCode = 95;\\n    companyId = \\\"BE_HM\\\";\\n    discountable = 1;\\n    exchangeable = 1;\\n    itemId = 101064025138011;\\n    languageCode = eng;\\n    noos14 = \\\"09258384394951,09258387434951\\\";\\n    sizeCode = \\\"163-011\\\";\\n    status = 1;\\n    taxGroup = 1;\\n    taxRegion = BE;\\n    tradeItemDesc = \\\"Jersey basic\\\";\\n    withTax = 1;\\n})\"\n)",
    "NSConstraintConflict (0x60000067fc00) for constraint (\n    itemId\n): database: (null), conflictedObjects: (\n    \"<TillData: 0x6080002cecb0> (entity: TillData; id: 0x6080002218e0 <x-coredata:///TillData/t7807C999-528C-4616-A012-592A3D77D28D5> ; data: {\\n    colorCode = 95;\\n    companyId = \\\"BE_HM\\\";\\n    discountable = 1;\\n    exchangeable = 1;\\n    itemId = 101064025138010;\\n    languageCode = eng;\\n    noos14 = \\\"09258384374953,09258387354952\\\";\\n    sizeCode = \\\"163-010\\\";\\n    status = 1;\\n    taxGroup = 1;\\n    taxRegion = BE;\\n    tradeItemDesc = \\\"Jersey basic\\\";\\n    withTax = 1;\\n})\",\n    \"<TillData: 0x6080002cf2d0> (entity: TillData; id: 0xd000000000180002 <x-coredata://6A608EA5-F8C8-4272-8C10-8621BB730066/TillData/p6> ; data: {\\n    colorCode = 95;\\n    companyId = \\\"BE_HM\\\";\\n    discountable = 1;\\n    exchangeable = 1;\\n    itemId = 101064025138010;\\n    languageCode = eng;\\n    noos14 = \\\"09258384374953,09258387354952\\\";\\n    sizeCode = \\\"163-010\\\";\\n    status = 1;\\n    taxGroup = 1;\\n    taxRegion = BE;\\n    tradeItemDesc = \\\"Jersey basic\\\";\\n    withTax = 1;\\n})\",\n    \"<TillData: 0x6000002ce9a0> (entity: TillData; id: 0x600000624620 <x-coredata:///TillData/t7807C999-528C-4616-A012-592A3D77D28D15> ; data: {\\n    colorCode = 95;\\n    companyId = \\\"BE_HM\\\";\\n    discountable = 1;\\n    exchangeable = 1;\\n    itemId = 101064025138010;\\n    languageCode = eng;\\n    noos14 = \\\"09258384374953,09258387354952\\\";\\n    sizeCode = \\\"163-010\\\";\\n    status = 1;\\n    taxGroup = 1;\\n    taxRegion = BE;\\n    tradeItemDesc = \\\"Jersey basic\\\";\\n    withTax = 1;\\n})\",\n    \"<TillData: 0x6080002d1e20> (entity: TillData; id: 0x608000229160 <x-coredata:///TillData/t7807C999-528C-4616-A012-592A3D77D28D11> ; data: {\\n    colorCode = 95;\\n    companyId = \\\"BE_HM\\\";\\n    discountable = 1;\\n    exchangeable = 1;\\n    itemId = 101064025138010;\\n    languageCode = eng;\\n    noos14 = \\\"09258384374953,09258387354952\\\";\\n    sizeCode = \\\"163-010\\\";\\n    status = 1;\\n    taxGroup = 1;\\n    taxRegion = BE;\\n    tradeItemDesc = \\\"Jersey basic\\\";\\n    withTax = 1;\\n})\"\n)"
)}
任何帮助都会很有帮助

------编辑------

从tableView中删除并关闭应用程序后,重新启动应用程序,我可以按预期再次加载数据,但只要我停留在应用程序中导航到应用程序的不同部分,然后返回,我就无法加载数据,即使调试告诉我,当我进入tableView时,它是空的,但当我尝试加载数据时,我会收到错误

显示持久存储为空的调试

2016-11-23 16:09:04.106 NWMobileTill[1554:32365] pimItemsArray holds (
)
2016-11-23 16:09:04.106 NWMobileTill[1554:32365] fetchReuestError holds (null)
正如您所看到的,支持tableview的数组是空的,获取请求是空的,因此持久存储是空的,如果它是空的,为什么我不能重新加载数据

这是填充tableView的代码

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];

NSError *error = nil;

// Fetch the devices from persistent data store
NSManagedObjectContext *context = self.persistentContainer.viewContext;
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] initWithEntityName:@"TillData"];
self.pimItems = [[context executeFetchRequest:fetchRequest error:&error] mutableCopy];

if([NWTillHelper isDebug] == 1) {
    NSLog(@"pimItemsArray holds %@", self.pimItems);
    NSLog(@"fetchReuestError holds %@", error);
}

[self.tableView reloadData];
}

问题是我没有在所有地方都一致地使用appDelegate

WebServices类中的以下行需要位于所有位置

AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication]delegate];

感谢Vinodh和Flexicoder指出这一点

对不起,我不确定你的意思,我阅读了链接,我正在做同样的事情,只是没有在NSManagedObject上循环,因为我只担心表中的一行。因此,我调用deleteObject,然后保存上下文,该上下文应该从持久存储中删除该对象。如果我在表中执行删除操作,退出应用程序,启动应用程序,则它可以工作,但如果我留在应用程序中,返回主菜单,然后返回管理菜单以加载数据,则它无法工作。我无法读取它们,就我所见,它们不在那里,下面的调试确认,当我加载Tableview并从持久性存储中读取其空值时,
appDelegate.persistentContainer.viewContext
self.persistentContainer.viewContext
指向相同的
context
AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication]delegate];