NSDictionary allkeys to UITableViewCell - ios

Question

I am trying to get my NSdictionary values into a UITableViewCell. Here is my dictionary format:
{
date = "3/4/14, 3:33:01 PM Pacific Standard Time";
weight = 244;
}
Here is the code I'm using to populate my uitableview (which is not working).
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *simpleTableIdentifier = #"WeightCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:simpleTableIdentifier];
}
NSArray* allKeys = [weights allKeys];
NSDictionary *obj = [allKeys objectAtIndex: indexPath.row];
cell.textLabel.text = [obj objectForKey: #"date"];
cell.detailTextLabel.text = [obj objectForKey:#"weight"];
return cell;
}

Answer 1

You should try initialising the array for the tableView outside of the tableView itself... something along the lines of
- (void)viewDidLoad
{
[super viewDidLoad];
_allKeys = [[NSMutableArray alloc] initWithArray:[weights allKeys]];
}
Once you have initialised that data you can access it throughout the process. Also to find out how many rows your tableview needs.
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [_allKeys count];
}
Then when you access the array into a dictionary it has retained the row count and can access it properly.
NSDictionary *obj = [_allKeys objectAtIndex: indexPath.row];
cell.textLabel.text = [obj objectForKey: #"date"];
cell.detailTextLabel.text = [obj objectForKey:#"weight"];
From what I can see the dictionary cant access the array at your indexPath.row because you haven't initialised the array anywhere before you use it in your tableView.
Hope that helps, T

Answer 2

Some of the other posters have good suggestions. However, this line:
NSDictionary *obj = [allKeys objectAtIndex: indexPath.row];
Is wrong. allKeys is an array of your dictionary keys, which are presumably strings.
So, you want code like this instead:
NSString *thisKey = allKeys[indexPath.row];
NSDictionary *obj = weights[thisKey];
Note that I am using the new Objective C literal syntax. The expression weights[thisKey] is equivalent to [weights objectForKey: thisKey]

Answer 3

I don't see the definition of the weights object. If you want to keep adding NSDictionary's to an array, you need to use an NSMutableArray, and you'll probably want to do that by setting it as a #property on your class. Let's say you added it like this:
#property (strong, nonatomic) NSMutableArray *weights;
Then in your tableView:cellForRowAtIndexPath: method you'll want to get the NSDictionary corresponding to that line by using self.weights[indexPath.row]. Also don't forget to instantiate weights before using it, otherwise it will return nil and no objects are going to be added to it.
P.S.: the user provided some context here and what he probably needs is Core Data.