UIPickerview gives questionmarks back instead of data - objective-c

Question

EDIT
I have a UIPickerview and I want do fill it up with data from my NSMutualArray. I have tested if something is in my array with NSLog and i get the data back. But it will not fill up my pickerviewer
I have this methods for my pickerviewer.
- (NSString *)pickView:(UIPickerView *)pickview titleForRow:(NSInteger)row forComponent:(NSInteger)component{
return [dataArray objectAtIndex:row];
}
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView{
return 1;// assuming a single spinning wheel of strings (not split into left/right for example)
}
-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{
return [json count]; // the number of strings that your parser finds and adds to the array
}
To get my data out of my JSON I use these two methods. And i call the start function in my viewdidload.
-(void) getData:(NSData *) data{
NSError *error;
json = [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:&error];
}
-(void) start {
NSURL *url = [NSURL URLWithString:kGETUrl];
NSData *data = [NSData dataWithContentsOfURL:url];
[self getData:data];
}
I have also a button which hides and shows my UIPickerviewer.
-(IBAction)setPicker:(id)sender{
if (pickview.hidden == TRUE) {
[pickview setHidden:NO];
[pickview setDelegate:self];
[pickview setDataSource:self];
[pickview reloadAllComponents];
}else {
[pickview setHidden:YES];
[pickview setDelegate:self];
[pickview setDataSource:self];
[pickview reloadAllComponents];
}
}
I use this method for filling up my array.
-(void) fillArray{
dataArray = [[NSMutableArray alloc] init];
for (int i=0; i<[json count]; i++) {
NSDictionary *info = [json objectAtIndex:i];
[dataArray addObject:[info objectForKey:#"Use_naam"]];
}
NSLog(#"%#\n",dataArray);
}
And i call it in my viewdidload.
- (void)viewDidLoad
{
[super viewDidLoad];
[self start];
[self fillArray];
// Do any additional setup after loading the view, typically from a nib.
}
Anybody knows what I am doing wrong ?

Answer 1

When you see a number of question marks matching the expected number of rows it's usually the methods that returns the title or view for the rows that are missing.
This can either be because the UIPickerViews delegate is not set (you did that) or because the signature is not correct.
Your signature is off. It needs to be exactly:
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component;
^^^^
Most commonly people forget that you have to set the UIPickerView delegate and datasource.