我一直在努力弄清楚如何在我的核心数据和我的 SQL 数据库之间建立连接。该数据库未预先填充,但在启动时将在许多不同的用户中使用。
斯坦福大学提供的 Core Data & iCloud 课程我已经学习了 3 次,但无济于事。我还彻底研究了 iOS 中的 SQLite/SQL 关系数据库,但无济于事。我唯一的其他选择就是来到这里,发布我能发布的所有代码,并祈祷有人会为我解答。所以这里...
AppDelegate.m
- (void)saveContext
{
NSError *error = nil;
NSManagedObjectContext *managedObjectContext = self.managedObjectContext;
if (managedObjectContext != nil) {
if ([managedObjectContext hasChanges] && ![managedObjectContext save:&error]) {
NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
abort();
}
}
}
#pragma mark - Core Data stack
- (NSManagedObjectContext *)managedObjectContext
{
if (_managedObjectContext != nil) {
return _managedObjectContext;
}
NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
if (coordinator != nil) {
_managedObjectContext = [[NSManagedObjectContext alloc] init];
[_managedObjectContext setPersistentStoreCoordinator:coordinator];
}
return _managedObjectContext;
}
- (NSManagedObjectModel *)managedObjectModel
{
if (_managedObjectModel != nil) {
return _managedObjectModel;
}
NSURL *modelURL = [self applicationDocumentsDirectory];
_managedObjectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];
return _managedObjectModel;
}
- (NSPersistentStoreCoordinator *)persistentStoreCoordinator
{
if (_persistentStoreCoordinator != nil) {
return _persistentStoreCoordinator;
}
NSURL *storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"shindy.sqlite"];
NSError *error = nil;
_persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:[self managedObjectModel]];
if (![_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeURL options:nil error:&error]) {
NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
abort();
}
return _persistentStoreCoordinator;
}
#pragma mark - Application's Documents directory
- (NSURL *)applicationDocumentsDirectory
{
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *path = [documentsDirectory stringByAppendingPathComponent:@"shindy.sqlite"];
return [NSURL fileURLWithPath:path];
}
主视图控制器.m
- (void)setupFetchedResultsController
{
NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Shindy"];
request.sortDescriptors = [NSArray arrayWithObjects:
[NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES],
[NSSortDescriptor sortDescriptorWithKey:@"dateAndTime" ascending:YES],
[NSSortDescriptor sortDescriptorWithKey:@"photo" ascending:YES],
[NSSortDescriptor sortDescriptorWithKey:@"details" ascending:YES],
[NSSortDescriptor sortDescriptorWithKey:@"timePosted" ascending:YES],
[NSSortDescriptor sortDescriptorWithKey:@"location" ascending:YES],
nil];
self.fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:request
managedObjectContext:self.shindyDatabase.managedObjectContext
sectionNameKeyPath:nil
cacheName:nil];
}
- (void)fetchShindyDataIntoDocument:(UIManagedDocument *)document
{
dispatch_queue_t fetchQ = dispatch_queue_create("Shindy Fetcher", nil);
dispatch_async(fetchQ, ^{
NSArray *shindys = [[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask];
NSLog(@"shindys = %@", shindys);
[document.managedObjectContext performBlock:^{
for (NSDictionary *shindyInfo in shindys) {
[Shindy shindyWithShindyDBInfo:shindyInfo inManagedObjectContext:document.managedObjectContext];
NSLog(@"fire");
}
}];
});
}
- (void)useDocument
{
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *path = [documentsDirectory stringByAppendingPathComponent:@"shindy.sqlite"];
if (![[NSFileManager defaultManager] contentsOfDirectoryAtPath:path error:nil]) {
[self.shindyDatabase saveToURL:self.shindyDatabase.fileURL forSaveOperation:UIDocumentSaveForCreating completionHandler:^(BOOL success) {
[self setupFetchedResultsController];
[self fetchShindyDataIntoDocument:self.shindyDatabase];
}];
} else if (self.shindyDatabase.documentState == UIDocumentStateClosed) {
[self.shindyDatabase openWithCompletionHandler:^(BOOL success) {
[self setupFetchedResultsController];
}];
} else if (self.shindyDatabase.documentState == UIDocumentStateNormal) {
[self setupFetchedResultsController];
}
}
- (void)setShindyDatabase:(UIManagedDocument *)shindyDatabase
{
[self useDocument];
}
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[self fetchShindyDataIntoDocument:self.shindyDatabase];
if (!self.shindyDatabase) {
[self setShindyDatabase:self.shindyDatabase];
}
}
Shindy+ShindyDB.m
+ (Shindy *)shindyWithShindyDBInfo:(NSDictionary *)shindyInfo
inManagedObjectContext:(NSManagedObjectContext *)context
{
Shindy *shindy = nil;
NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Shindy"];
NSSortDescriptor *dateAndTimeSort = [NSSortDescriptor sortDescriptorWithKey:@"dateAndTime" ascending:YES];
NSSortDescriptor *detailsSort = [NSSortDescriptor sortDescriptorWithKey:@"details" ascending:YES];
NSSortDescriptor *locationSort = [NSSortDescriptor sortDescriptorWithKey:@"location" ascending:YES];
NSSortDescriptor *nameSort = [NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES];
NSSortDescriptor *photoSort = [NSSortDescriptor sortDescriptorWithKey:@"photo" ascending:YES];
NSSortDescriptor *timePostedSort = [NSSortDescriptor sortDescriptorWithKey:@"timePosted" ascending:YES];
// title
request.sortDescriptors = [NSArray arrayWithObjects:dateAndTimeSort, detailsSort, locationSort, nameSort, photoSort, timePostedSort, nil];
NSError *error = nil;
NSArray *matches = [context executeFetchRequest:request error:&error];
if (!matches || ([matches count] > 1)) {
// handle error
} else if ([matches count] == 0) {
shindy = [NSEntityDescription insertNewObjectForEntityForName:@"Shindy" inManagedObjectContext:context];
shindy.dateAndTime = [shindyInfo objectForKey:@"dateAndTime"];
shindy.details = [shindyInfo objectForKey:@"details"];
shindy.location = [shindyInfo objectForKey:@"location"];
shindy.name = [shindyInfo objectForKey:@"name"];
shindy.photo = [shindyInfo objectForKey:@"photo"];
shindy.timePosted = [shindyInfo objectForKey:@"timePosted"];
// title
// Guestlist? The rest?
// Use below for reference
shindy.whoseShindy = [User userWithName:[shindyInfo objectForKey:@"whoseShindy"] inManagedObjectContext:context];
} else {
shindy = [matches lastObject];
}
shindy = [NSEntityDescription insertNewObjectForEntityForName:@"Shindy" inManagedObjectContext:context];
shindy.dateAndTime = [shindyInfo objectForKey:@"dateAndTime"];
shindy.details = [shindyInfo objectForKey:@"details"];
shindy.location = [shindyInfo objectForKey:@"location"];
shindy.name = [shindyInfo objectForKey:@"name"];
shindy.photo = [shindyInfo objectForKey:@"photo"];
shindy.timePosted = [shindyInfo objectForKey:@"timePosted"];
return shindy;
}
添加ShindyViewController.m
- (void)saveShindyToDatabase
{
NSArray *shindys = [[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask];
[self.shindyDatabase.managedObjectContext performBlock:^{
for (NSDictionary *shindyInfo in shindys) {
[Shindy shindyWithShindyDBInfo:shindyInfo inManagedObjectContext:self.shindyDatabase.managedObjectContext];
NSURL *url = [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
// url = [url URLByAppendingPathComponent:@"Default Shindy Database"];
self.shindyDatabase = [[UIManagedDocument alloc] initWithFileURL:url];
[self.shindyDatabase setValue:self.detailView.text forKey:@"details"];
if (FBSession.activeSession.isOpen) {
[[FBRequest requestForMe] startWithCompletionHandler:
^(FBRequestConnection *connection, NSDictionary<FBGraphUser> *user, NSError *error) {
if (!error) {
self.name = user.name;
self.photo.profileID = user.id;
self.username = user.username;
}
}];
}
[self.shindyDatabase setValue:self.name forKey:@"name"];
[self.shindyDatabase setValue:self.photo forKey:@"photo"];
[self.shindyDatabase setValue:self.username forKey:@"username"];
// [Guest guestWithName:self.name username:self.username photo:self.photo inManagedObjectContext:self.shindyDatabase.managedObjectContext];
[self.shindyDatabase setValue:self.locationManager.location forKey:@"location"];
[self.shindyDatabase setValue:self.dateAndTimePicker.date forKey:@"dateAndTime"];
}
}];
}
我知道我要的东西太多了,但我已经用尽了我可以使用的每一个资源。如果有人能指出我正确的方向,我将永远感激不尽!