Question

I am working with coredata and successfully saved the data in data storage but when I try to output what I stored using table view ,I am not able to do it.

Here the user will enter and click save ..so when he goes back..I want the table to populated with what name he or she has entered.

So I wrote the below code for saving and find data:

- (void) saveData
{
    coredata123AppDelegate *appDelegate = 
    [[UIApplication sharedApplication] delegate];

    NSManagedObjectContext *context = 
    [appDelegate managedObjectContext];
    Contacts *newContact;
    newContact = [NSEntityDescription
                  insertNewObjectForEntityForName:@"Contacts"
                  inManagedObjectContext:context];
    [newContact setValue:name.text forKey:@"name"];
    [newContact setValue:address.text forKey:@"address"];
    [newContact setValue:phone.text forKey:@"phone"];
    name.text = @"";
    address.text = @"";
    phone.text = @"";
    NSError *error;
    [context save:&error];
    status.text = @"Contact saved";    
}

- (void) findContact
{
    coredata123AppDelegate *appDelegate = 
    [[UIApplication sharedApplication] delegate];
    NSManagedObjectContext *context = 
    [appDelegate managedObjectContext];
    NSEntityDescription *entityDesc = 
    [NSEntityDescription entityForName:@"Contacts" 
                inManagedObjectContext:context];
    NSFetchRequest *request = [[NSFetchRequest alloc] init];
    [request setEntity:entityDesc];
    NSPredicate *pred = 
    [NSPredicate predicateWithFormat:@"(name = %@)", 
     name.text];
    [request setPredicate:pred];
    NSManagedObject *matches = nil;
    NSError *error;
    NSArray *objects = [context executeFetchRequest:request 
                                              error:&error];

    for(Contacts *info in objects)
    {
        NSLog(@"Name:%@",info.name);
        NSLog(@"Address:%@",info.address);
    }   
    if ([objects count] == 0) {
        status.text = @"No matches";
    } else {
        matches = [objects objectAtIndex:0];
        address.text = [matches valueForKey:@"address"];
        phone.text = [matches valueForKey:@"phone"];
        status.text = [NSString stringWithFormat:
                       @"%d matches found", [objects count]];
    }
    [request release];


}

And to populate the table view i have written this code..

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];

    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription 
                                   entityForName:@"Contacts" inManagedObjectContext:context];
    [fetchRequest setEntity:entity];
    NSError *error;
    self.contacts = [context executeFetchRequest:fetchRequest error:&error];

    [fetchRequest release];

}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
    }


    Contacts *info =[contacts objectAtIndex:indexPath.row];
    cell.textLabel.text =info.name;
    cell.detailTextLabel.text=info.address;

    // Configure the cell...

    return cell;
}

Answer 1

Are you getting proper number of elements in this objects array?

NSArray *objects = [context executeFetchRequest:request 
                                          error:&error];

if not, try changing the predicate with,

[NSPredicate predicateWithFormat:@"name=%@", name.text];

Otherwise, your code seems correct to me.