好的,
我正在使用Magicalrecord进行核心数据实施。我的应用程序在第一次加载时会下载一堆信息。然后将该数据保存到核心数据中。这是在AppDelegate文件中完成的。但是,每当我的应用程序进入后台或终止时,数据都会丢失。这是带有选项方法的didFinishLaunching:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
NSLog(@"My app is starting");
[MagicalRecord setupAutoMigratingCoreDataStack];
//NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
if (![[NSUserDefaults standardUserDefaults] objectForKey:@"AGM_DataSetup"]) {
NSError* jsonError;
NSArray* json;
Reachability *reachability = [Reachability reachabilityForInternetConnection];
NetworkStatus internetStatus = [reachability currentReachabilityStatus];
if (internetStatus == NotReachable) {
NSLog(@"Offline");
NSString *filePath = [[NSBundle mainBundle] pathForResource:@"static" ofType:@"json"];
NSString *myJSON = [[NSString alloc] initWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:NULL];
json = [NSJSONSerialization JSONObjectWithData:[myJSON dataUsingEncoding:NSUTF8StringEncoding] options:kNilOptions error:&jsonError];
} else {
NSLog(@"Online");
NSData* data = [NSData dataWithContentsOfURL:
aWaterURL];
json = [NSJSONSerialization
JSONObjectWithData:data
options:kNilOptions
error:&jsonError];
}
if (!jsonError) {
[MagicalRecord cleanUp];
NSString* folderPath = [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSError *error = nil;
for (NSString *file in [[NSFileManager defaultManager] contentsOfDirectoryAtPath:folderPath error:&error])
{
[[NSFileManager defaultManager] removeItemAtPath:[folderPath stringByAppendingPathComponent:file] error:&error];
if(error)
{
NSLog(@"Delete error: %@", error.description);
}
}
[MagicalRecord setupCoreDataStackWithAutoMigratingSqliteStoreNamed:@"Anglers411.sqlite"];
NSLog(@"Initial Data Load");
for (id jsonArea in json) {
// Create an area
Area *area = [Area MR_createEntity];
area.name = [jsonArea objectForKey:@"name"];
area.bulletDescription = [jsonArea objectForKey:@"bulletDescription"];
area.uid = [jsonArea objectForKey:@"id"];
NSArray* jsonLocations = [jsonArea objectForKey:@"locations"];
for (id jsonLocation in jsonLocations) {
// create a location
Location *location = [Location MR_createEntity];
location.uid = [jsonLocation objectForKey:@"id"];
location.name = [jsonLocation objectForKey:@"name"];
location.desc = [jsonLocation objectForKey:@"desc"];
location.directions = [jsonLocation objectForKey:@"directions"];
location.bulletDescription = [jsonLocation objectForKey:@"bulletDescription"];
location.area = area;
NSArray* jsonBugs = [jsonLocation objectForKey:@"bugs"];
for (id jsonBug in jsonBugs) {
Bug *bug = [Bug MR_createEntity];
bug.name = [jsonBug objectForKey:@"name"];
bug.spring = [jsonBug objectForKey:@"spring"];
bug.summer = [jsonBug objectForKey:@"summer"];
bug.fall = [jsonBug objectForKey:@"fall"];
bug.winter = [jsonBug objectForKey:@"winter"];
bug.location = location;
}
}
}
[[NSManagedObjectContext MR_defaultContext] MR_saveToPersistentStoreWithCompletion:^(BOOL success, NSError *error) {
if (success) {
NSLog(@"You successfully saved your context.");
} else if (error) {
NSLog(@"Error saving context: %@", error.description);
}
}];
// Set User Default to prevent another preload of data on startup.
[[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"AGM_DataSetup"];
[[NSUserDefaults standardUserDefaults] synchronize];
}
}
return YES;
}
这是我在applicationDidEnterBackground和ApplicationWillTerminate中使用的方法:
- (void)saveContext {
[MagicalRecord cleanUp];
}
感谢您对此提供任何帮助。我已经在这里阅读了每个魔法记录的非持久性问题,并且没有找到任何有用的东西。
保重,
本
答案 0 :(得分:0)
对不起,
经过进一步的探索,我发现如果你想让它们成为同一个堆栈,通常不会设置2个不同名称的核心数据堆栈......我已经纠正了这个问题。