Question

I created an object that contains properties that in the end will manage data that lives in core data.

I would like to create methods within this object to set data that would be saved into core data as well as method that gets all data from core data and sets properties in the object so I can have everything contained in one object.

The object I am using to set the object’s properties is not setting it properly. It will set them within part of the method but in another part of the method and outside of the method the properties are null.

It is a scoping problem that I clearly do not have my head around so I am turning to the experts. Please advise where I have gone astray. Thanks again for your assistance in advance!
Ed

Object Definitions:
.m file

 @implementation GenObject

 @synthesize name = _name;
 @synthesize address = _address;

 - (void)getGenData
 {
      MyAppDelegate *genDataAppDelegate = [[UIApplication sharedApplication] delegate]; // Create a variable to the app delegate
      NSManagedObjectContext *genDataContext = [genDataAppDelegate managedObjectContext]; // Create a context

      NSEntityDescription *getDataEntityDesc = [NSEntityDescription entityForName:@"GeneralData" inManagedObjectContext:genDataContext];  // Create a description for the core data
      NSFetchRequest *genDataRequest = [[NSFetchRequest alloc] init]; // Create a Fetch request for the core data

      [genDataRequest setEntity:getDataEntityDesc]; // Set the fetch requests entity description

      NSManagedObject *genDataMatches = nil; // Create a managed object
      NSError *genDataCoreError; // Create an error object

      NSArray *genDataCoreObjectsArray = [genDataContext executeFetchRequest:genDataRequest error:&genDataCoreError]; // Fetch the core data and load the objects array
      int genDataCoreObjectsCount = [genDataCoreObjectsArray count]; // Get the count of the objects fetched

      if ([genDataCoreObjectsArray count] == 0) // Check to see if there were any objects fetched
      {
          //NSLog(@"No matches");
      } 
      else // If there were objects fetched then loop over them
     {
         for(int y = 0; y < genDataCoreObjectsCount; y++) // Loop over the objects fetched
         {
             genDataMatches = [genDataCoreObjectsArray objectAtIndex:y]; // Get the current object
             self.name = [[genDataMatches valueForKey:@"name"] retain];
             self.address = [[genDataMatches valueForKey:@"address"] retain];
             NSLog(@"BASE URL %@",self.baseurl); // WORKS HERE!!!
        }   
    }
    NSLog(@"BASE URL %@",self.baseurl); // DOES NOT WORK HERE!!!
 }
 @end

.h file

 @interface GenObject : NSObject
 {
     NSString    *_name;    
     NSString    *_address;   
 }

 @property (nonatomic, retain) NSString  *name;
 @property (nonatomic, retain) NSString  *address;

 - (void)setGenIntitalData;
 @end

And if I try to call it from within a different class like say a ViewController as such…
NOTE: Within the viewController genDataObj is a property of the viewController

 - (void)viewDidLoad
 {
     self.genDataObj = [GenData new];
     [self.genDataObj setGenIntitalData]; // Setup the gendata core data
     [self.genDataObj getGenData]; // Set up the gen data from the core data

     NSLog(@"NAME: %@", self.genDataObj.name); // NAME IS nil HERE!!!!

     [super viewDidLoad];
 }

Answer 1

You should confirm that your NSManagedObject is actually returning data. Try this:

 - (void)getGenData
 {
    MyAppDelegate *appDelegate = (MyAppDelegate *)[[UIApplication sharedApplication] delegate];
    NSManagedObjectContext *context = [appDelegate managedObjectContext]; 
    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"GeneralData"];

    NSManagedObject *genData = nil;
    NSError *fetchError = nil;
    NSArray *genDataObjects = [context executeFetchRequest:request error:&fetchError];
    [request release];
    if( fetchError )
        NSLog(@"%s - ERROR fetching genData: %@,%@",__FUNCTION__,fetchError,[fetchError userInfo]);
    else
    {
        if( [genDataObjects count] == 0 )
            NSLog(@"%s - No matches for genData",__FUNCTION__);
        else
        {
            genData = [genDataObjects objectAtIndex:0];
            NSLog(@"%s - genData.name = %@",__FUNCTION__,[genData valueForKey:@"name"]);
            self.name = [genData valueForKey:@"name"];
            self.address = [genData valueForKey:@"address"];
        }
    }
}

In setGenIntitalData are you saving your changes to the persistent store? I assume that in setGenIntitalData you are creating initial settings; but if the NSManagedObject isn’t saved, then your subsequent fetch will yield invalid data.