I am trying to get a JSON to iOS app, but keep getting NULL values..
- (id)initWithDictionary:(NSDictionary *)dictionary {
    self.name      = [dictionary valueForKey:@"name"];
    self.amount    = [NSString stringWithFormat:@"%@", 
                      [dictionary valueForKey:@"amount"]];
    self.goalId    = [dictionary valueForKey:@"id"];
    self.createdAt = [dictionary valueForKey:@"created_at"];
    self.updatedAt = [dictionary valueForKey:@"updated_at"];
    return self;
}
+ (NSArray *)findAllRemote {
    NSURL *url = [NSURL URLWithString:@"http://localhost:3000/goals.json"];
    NSError *error = nil;
    NSString *jsonString = 
    [NSString stringWithContentsOfURL:url 
                         encoding:NSUTF8StringEncoding 
                            error:&error];
    NSLog(@"my string = %@",  jsonString);
   NSMutableArray *goals = [NSMutableArray array];
   if (jsonString) {
       SBJSON *json = [[SBJSON alloc] init];    
       NSArray *results = [json objectWithString:jsonString error:&error];
       [json release];
       for (NSDictionary *dictionary in results) {
           Goal *goal = [[Goal alloc] initWithDictionary:dictionary];
           [goals addObject:goal];
           [goal release];
        }
    }
    return goals;    
}
JSON string looks correct:
my string = [{"goal":{"amount":"100.0","created_at":"2011-08-20T00:55:34Z","id":1,"name":"User","updated_at":"2011-08-20T00:55:34Z"}},{"goal":{"amount":"200.0","created_at":"2011-08-20T00:56:48Z","id":2,"name":"User2","updated_at":"2011-08-20T00:56:48Z"}},{"goal":{"amount":"19999.0","created_at":"2011-08-20T19:15:10Z","id":3,"name":"This is MY GOAL","updated_at":"2011-08-20T19:15:10Z"}},{"goal":{"amount":"0.0","created_at":"2011-08-20T20:46:44Z","id":4,"name":"goal","updated_at":"2011-08-20T20:46:44Z"}}]
I am missing something basic I guess..
UPDATE:
Here is a line that returns NULL (from another class):
- (IBAction)refresh {
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
self.goals = [Goal findAllRemote];
[self.tableView reloadData];
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
}
- (void)viewDidLoad
{
[super viewDidLoad];
self.title = @"Goals";
self.navigationItem.leftBarButtonItem = self.editButtonItem;
UIBarButtonItem *refreshButton = [[UIBarButtonItem alloc] 
                                      initWithBarButtonSystemItem:UIBarButtonSystemItemRefresh
                                  target:self 
开发者_StackOverflow                                  action:@selector(refresh)];
self.navigationItem.rightBarButtonItem = refreshButton;
[refreshButton release];
[self refresh];
}
 - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"GoalCellId";
UITableViewCell *cell = 
[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
    cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1
                                   reuseIdentifier:CellIdentifier] autorelease];
}
Goal *goal = [goals objectAtIndex:indexPath.row];
cell.textLabel.text = goal.name;
cell.detailTextLabel.text = goal.amount;
return cell;
}
goal.name and goal.amount are Null..
This may not be part of your issue, but you should be calling [self init] (or more importantly, [super init] via inheritance):
- (id)initWithDictionary:(NSDictionary *)dictionary {
    if (self = [self init]) {
      self.name      = [dictionary valueForKey:@"name"];
      self.amount    = [NSString stringWithFormat:@"%@", 
                      [dictionary valueForKey:@"amount"]];
      self.goalId    = [dictionary valueForKey:@"id"];
      self.createdAt = [dictionary valueForKey:@"created_at"];
      self.updatedAt = [dictionary valueForKey:@"updated_at"];
    }
    return self;
}
Also:
    for (NSDictionary *dictionary in results) {
       Goal *goal = [[Goal alloc] initWithDictionary:
          [dictionary objectForKey:@"goal"]];
       [goals addObject:goal];
       [goal release];
    }
Key change is [dictionary objectForKey:@"goal"] in line 3. 
The JSON array is of objects with a single goal member, with the properties that your initWithDictionary method is looking for.
 
         
                                         
                                         
                                         
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