importing sqlite to coredata

Question

I have imported sqlite prepopulated dbs to my coredata projects before, but now I have created a project in the 3.2.5. xcode, wich changes nsurl for nstring in the AppDelegate, so I went with that, But now my sqlite doesnt import to the project,

if I leave my PersistentStoreCoordinator to create the new db blank it works fine,

 NSURL *storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"ChildCare_v02.sqlite"];

but when I change the code to import the prepopulated db (called the same just to clarify), it gives me a warning and crashes,

- (NSPersistentStoreCoordinator *)persistentStoreCoordinator {
if (persistentStoreCoordinator_ != nil) {
return persistentStoreCoordinator_;
}
NSString *storePath = [[self applicationDocumentsDirectory] stringByAppendingPathComponent: @"ChildCare_v02.sqlite"]; //WARNING !! here
NSURL *storeUrl = [NSURL fileURLWithPath:storePath]; 
//NSURL *storeURL = [[self applicationDocumentsDirectory]    URLByAppendingPathComponent:@"ChildCare_v02.sqlite"]; //actual SDK style for blank db

// Put down default db if it doesn't already exist
    NSFileManager *fileManager = [NSFileManager defaultManager];
   if (![fileManager fileExistsAtPath:storePath]) {
    NSString *defaultStorePath = [[NSBundle mainBundle]  pathForResource:@"ChildCare_v02" ofType:@"sqlite"];
    if (defaultStorePath) {
        [fileManager copyItemAtPath:defaultStorePath toPath:storePath error:NULL];
    }
    }
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_;
    }

THIS is the crash log in console

-[NSURL stringByAppendingPathComponent:]: unrecognized selector sent to instance  0x5b40e50
 2011-02-15 21:06:59.245 Staff_02c[469:207] *** Terminating app due to uncaught  exception 'NSInvalidArgumentException', reason: '-[NSURL stringByAppendingPathComponent:]:     unrecognized selector sent to instance 0x5b40e50'

How to fix this please?? Just when I tough I was getting Core data !! dough!!

Answer 1

The crash isn't related specifically to Core Data.

Looks like you're calling a method that doesn't exist.

In NSURL the method is "URLByAppendingPathComponent".

If you want stringByAppendingPathComponent, that's in NSString.

You most likely had a warning for this during build.

Answer 2

stringByAppendingPathComponent this method is instance method of NSString class.so you cant access this method on NSURL.

so for correction change this line

NSString *storePath = [[self applicationDocumentsDirectory] stringByAppendingPathComponent: @"ChildCare_v02.sqlite"];

by this code

 NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *writableDBPath = [documentsDirectory stringByAppendingPathComponent:@"ChildCare_v02.sqlite"];

Answer 3

apple changed the helper method that returns the application dictionary in the core data templates.

You are relying on this version:

- (NSString *)applicationDocumentsDirectory {
    return [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
}

but apple changed it to this version

- (NSURL *)applicationDocumentsDirectory {
    return [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
}

---

to fix it, just change this.

NSString *storePath = [[self applicationDocumentsDirectory] stringByAppendingPathComponent: @"ChildCare_v02.sqlite"]; //WARNING !! here
NSURL *storeUrl = [NSURL fileURLWithPath:storePath]; 
//NSURL *storeURL = [[self applicationDocumentsDirectory]    URLByAppendingPathComponent:@"ChildCare_v02.sqlite"]; //actual SDK style for blank db

to this

//NSString *storePath = [[self applicationDocumentsDirectory] stringByAppendingPathComponent: @"ChildCare_v02.sqlite"]; //WARNING !! here
//NSURL *storeUrl = [NSURL fileURLWithPath:storePath]; 
NSURL *storeUrl = [[self applicationDocumentsDirectory]    URLByAppendingPathComponent:@"ChildCare_v02.sqlite"]; //actual SDK style for blank db

sorry, but omfg

Answer 4

You don't need to use NSString paths at all, it can all be done with NSURL methods.

NSURL *storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"Database.sqlite"];

// If the database doesn't exist copy in the default one
if (![storeURL checkResourceIsReachableAndReturnError:NULL])
{
    NSURL *defaultStoreURL = [[NSBundle mainBundle] URLForResource:@"Database" withExtension:@"sqlite"];

    if ([defaultStoreURL checkResourceIsReachableAndReturnError:NULL])
    {
        NSFileManager *fileManager = [NSFileManager defaultManager];
        [fileManager copyItemAtURL:defaultStoreURL toURL:storeURL error:NULL];
    }
}

Answer 5

thanks Ishu, you helped me a lot by pointing the NSArray way!!!

this was the solution I ended up by enlightenment !

- (NSPersistentStoreCoordinator *)persistentStoreCoordinator {

if (persistentStoreCoordinator_ != nil) {
    return persistentStoreCoordinator_;
}



NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *writableDBPath = [documentsDirectory stringByAppendingPathComponent:@"ChildCare_v02.sqlite"];

NSString *storePath = [[NSBundle mainBundle] pathForResource:@"ChildCare_v02" ofType:@"sqlite"];


NSURL *storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"ChildCare_v02.sqlite"]; //este es el que sirve!!! CREE ESTE

NSLog(@"store URL %@", storeURL);

    // Put down default db if it doesn't already exist
NSFileManager *fileManager = [NSFileManager defaultManager];
if (![fileManager fileExistsAtPath:writableDBPath]) {
    NSLog(@"proceda aqui");
    NSString *defaultStorePath = [[NSBundle mainBundle] pathForResource:@"ChildCare_v02" ofType:@"sqlite"];
    NSLog(@"no existe todavia");
    NSLog(@"defalultStorePath %@", defaultStorePath);


    if (defaultStorePath) {
      [fileManager copyItemAtPath:defaultStorePath toPath:writableDBPath error:NULL];
        NSLog(@"storePath= %@", storePath);
    }
}    

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_;
    }

hope it helps some noob like me wanting to import prepopulated sqlite to a coredata db, note that first need to create blank db, to keep the structure and then populated (I used SQLite database browser to import CSV columns to my sqlite)

ss9