布尔值不会存储在核心数据栈

Question

我想简单地在我的核心数据堆栈中切换BOOL属性，并使用该coredata布尔在我的mainView中设置viewDidLoad中的UISwitch的“状态”。

以下情形： 开关关闭时，用户点击编辑（保存）的UIButton， - >是切换实体从@NO设置为@YES 下一次应用程序启动，在viewDidLoad中的settingSysTimeOverride属性，我取芯数据堆栈并查看settingSysTimeOverride的状态并使用它来设置我的UISwitch的“状态”。

但由于某种原因，我的价值不会被存储到核心数据堆栈。 整个项目都附上了，这里也是我的代码。

MainViewController.m

#import "MainViewController.h" 
#import "AppDelegate.h" 

@interface MainViewController() 

@property (nonatomic, strong)NSManagedObjectContext *managedObjectContext; 
@property (nonatomic, strong)NSFetchedResultsController *fetchedResultsController; 

@property (strong, nonatomic) NSMutableArray *settingsArray; 
@end 


@implementation MainViewController 

@synthesize editSetting; 

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil 

{ 
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; 

    if (self) { 

     // Custom initialization 
    } 
    return self; 
} 

- (NSManagedObjectContext *)managedObjectContext 

{ 
    return [(AppDelegate*)[[UIApplication sharedApplication]delegate]managedObjectContext]; 

} 

- (void)viewDidLoad 

{ 
    [super viewDidLoad]; 

    NSManagedObjectContext *context = [self managedObjectContext]; 
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; 
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Setting" inManagedObjectContext:context]; 

    [fetchRequest setEntity:entity]; 

    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"settingSysTimeOverride == %@", editSetting]; 

    [fetchRequest setPredicate:predicate]; 

    NSError *error; 
    NSArray *fetchedObjects = [context executeFetchRequest:fetchRequest error:&error]; 

    if (fetchedObjects == nil) { 
     NSLog(@"ERROR! %@ - %@", [error localizedDescription], [error userInfo]); 
    } else { 
     NSLog(@"FETCH SUCCESSFUL"); 
    } 

    if ((fetchedObjects.count) >0) { 
     // list array contents 
     for (int i=0; i < (fetchedObjects.count); i++) { 

      // output for debug purpose 

      NSLog(@"Array-index [%i]: %@", i, fetchedObjects[i]); 
     } 
    } 

    // check settingSysTimeOverride and set UISwitch-State 
    if (editSetting.settingSysTimeOverride.boolValue == 0) { 
     // turn switch to OFF - Position 
     _overrideSysTimeSwitch.on = NO; 
    } else { 
     // turn switch to ON - Position 
     _overrideSysTimeSwitch.on = YES; 
    } 
} 

- (void)didReceiveMemoryWarning 

{ 
    [super didReceiveMemoryWarning]; 
    // Dispose of any resources that can be recreated. 
} 

- (IBAction)editSave:(UIBarButtonItem *)sender 

{ 
    // toggle BOOL status of settingSysTimeOverride here 
    // 
} 

- (IBAction)overrideSysTime:(UISwitch *)sender 
{ 
} 

- (IBAction)timeFormat:(UISwitch *)sender { 
} 
@end 




MainViewController.h 
#import <UIKit/UIKit.h> 

#import "Setting.h" 

@interface MainViewController : UIViewController <NSFetchedResultsControllerDelegate> 
@property (nonatomic, strong)Setting *editSetting; 
@property (strong, nonatomic) IBOutlet UIBarButtonItem *editSaveButton 

@property (strong, nonatomic) IBOutlet UILabel *overrideSysTimeLabel; 
@property (strong, nonatomic) IBOutlet UILabel *timeFormatLabel; 

@property (strong, nonatomic) IBOutlet UISwitch *overrideSysTimeSwitch; 
@property (strong, nonatomic) IBOutlet UISwitch *timeFormatSwitch; 


- (IBAction)editSave:(UIBarButtonItem *)sender; 
- (IBAction)overrideSysTime:(UISwitch *)sender; 
- (IBAction)timeFormat:(UISwitch *)sender; 
@end 



AppDelegate.h 
#import <UIKit/UIKit.h> 

@interface AppDelegate : UIResponder <UIApplicationDelegate> 
@property (strong, nonatomic) UIWindow *window; 

@property (readonly, strong, nonatomic) NSManagedObjectContext *managedObjectContext; 
@property (readonly, strong, nonatomic) NSManagedObjectModel *managedObjectModel; 
@property (readonly, strong, nonatomic) NSPersistentStoreCoordinator *persistentStoreCoordinator; 

- (void)saveContext; 
- (NSURL *)applicationDocumentsDirectory; 

@end 

Setting.h

#import <Foundation/Foundation.h> 
#import <CoreData/CoreData.h> 

@interface Setting : NSManagedObject 
@property (nonatomic, retain) NSString * settingName; 
@property (nonatomic, retain) NSNumber * settingSysTimeOverride; 
@property (nonatomic, retain) NSNumber * settingTimeFormat; 
@end 





Setting.m 
#import "Setting.h" 

@implementation Setting 
@dynamic settingName; 
@dynamic settingSysTimeOverride; 
@dynamic settingTimeFormat; 

@end 

是否有人可以帮我这个???

Answer 1

这里是我做错了，我希望这将帮助其他人在未来避免在同样的问题上运行：

我忘了点我的NSManagedObject我取数组的开头。

NSManagedObject *matches; 
matches=[objects objectAtIndex:(0)]; 

在一块的代码是这样的：

NSManagedObjectContext *context; 
NSEntityDescription *entityDesc; 
NSFetchRequest *request; 

NSPredicate *pred; 
NSManagedObject *matches; 

NSArray *objects; 

NSUInteger elementsInArray; 

context = [self managedObjectContext]; 
entityDesc = [NSEntityDescription entityForName:@"Setting" inManagedObjectContext:context]; 
pred = [NSPredicate predicateWithFormat:@"(settingName = %@)", @"User-Settings"]; 

request = [[NSFetchRequest alloc] init]; 
[request setEntity:entityDesc]; 
[request setPredicate:pred]; 

matches = nil; 
NSError *errorFS = nil; 

if (!(objects = [context executeFetchRequest:request error:&errorFS])) { 
    // fetch failed 
    NSLog(@"Fetch failed: %@ - %@", [errorFS localizedDescription], [errorFS userInfo]); 
} else { 
    // fetch succeeded 
    NSLog(@"Fetch Succeeded"); 
} 

if ([objects count] == 0) 
{ // does not exist -> error? 
} else 
{ 
    matches=[objects objectAtIndex:(0)]; // <- HERE WAS THE ERROR !!!!! 
    // # system time override switch 
    if([[matches valueForKey:@"settingSysTimeOverride"] boolValue]) { 
    _sysTimeOverrideSwitch.on = YES; 
} else { 
    _sysTimeOverrideSwitch.on = NO; 
} 

}