iOS Parsing JSON value on UIPickerview xcode

[dankiiing]

I have a pickerview with which I would want to display values using JSON parsing. I am aware some questions on the site already tackle parsing and pickerview but mine is slightly different in regards to the structure of my json file. Here's a sample of the json file.

[
{
"model":"juice",
"id" :
  [
    {
        "version": "version01"
    },

    {
        "version": "version02"
    }

  ]
},
 {
"model":"cream",
"id" :
[
  {
      "version": "cream01"
  },

  {
      "version": "cream02"
  }
]
}
]

and my .m file

- (void)viewDidLoad
    {
    [super viewDidLoad];

    NSURL * serverhost = [NSURL URLWithString:@"http://my.json"];

    NSError *error;

    NSData  * Data  = [NSData  dataWithContentsOfURL: serverhost];

    self.modelsArray= [NSJSONSerialization JSONObjectWithData:Data   options:NSJSONReadingAllowFragments error:&error];

    NSLog(@"%@", modelsArray);
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
    return 2;
}

- (NSInteger)pickerView:(UIPickerView *)pickerView
numberOfRowsInComponent:(NSInteger)component
{
    if (component == departments)
        return [self.modelsArray count];
    return [self.versionsArray count];
}


#pragma mark Picker Delegate Methods
- (NSString *)pickerView:(UIPickerView *)pickerView
         titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
    if (component == departments)
          return [[self.modelsArray    objectAtIndex:row]objectForKey:@"model"];
    return [[[self.versionsArray objectAtIndex:row]objectForKey:@"model"]objectForKey:@"version"];
}

-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:    (NSInteger)component
{
    if (component == departments)
    {
        NSString * selectedRow = [[self.modelsArray objectAtIndex: row]    valueForKey:@"version"];
        NSArray * array = [sybreDepts objectForKey:selectedRow];
        self.
    }
}

@end

Basically when I select a model i.e juice or cream on the first column the second column should display its contents with key being 'versions' thus when juice is selected "version01" and "version02" should be displayed on the second column.

In regards to the line return

[[[self.versionsArray objectAtIndex:row]objectForKey:@"model"]objectForKey:@"version"];

I don't believe it was executed correctly as I get an error
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFString objectForKey:]: unrecognized selector sent to instance 0xa18c450' .

Any suggestions ? thanks

 

[dejo]

What is the type of [self.versionsArray objectAtIndex:row]? I suspect it's an NSString, therefore you can't call objectForKey: on it.

 

[dankiiing]

Thanks for you reply Dejo, im fairly new to json parsing , how do you suggest I fix this ? I had been on this for weeks

 

[dejo]

...how do you suggest I fix this ?

Reevaluate what you are storing in self.versionsArray. Your code suggests you are expecting it to be NSDictionary while the error suggests it is NSString.

How much do you know about basic debugging (breakpoints, examining variables values, etc.)?