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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