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UIPickerView does not display data

I followed youtube tutorials as well as tips here, but I can't get my UIPickerView to display its data. I populate the collector using three arrays, and I thought I implemented the code correctly, but obviously something is wrong. The collector displays the number of elements correctly, the problem is that they all display as "?"

I tried setting up the collector delegate to myself, but that didn't work either. Thanks in advance.

Here is my .h file:

@interface BACcalcViewController : UIViewController<UIPickerViewDataSource, UIPickerViewDelegate>
@property(strong, nonatomic) IBOutlet UIPickerView *personInfoPicker;
@property(strong, nonatomic) NSArray *heightsArray;
@property(strong, nonatomic) NSArray *weightsArray;
@property(strong, nonatomic) NSArray *timeArray;
@end

Here is my .m file:

@interface BACcalcViewController () <UIPickerViewDataSource, UIPickerViewDelegate>

@end

@implementation BACcalcViewController


@synthesize personInfoPicker, heightsArray, weightsArray, timeArray;
- (void)viewDidLoad
{

[super viewDidLoad];

heightsArray = [NSArray arrayWithObjects:
                         @"5ft 0in",
                         @"5ft 1in",
                         @"5ft 2in",
                         @"5ft 3in",
                         @"5ft 4in",
                         @"5ft 5in",
                         @"5ft 6in",
                         @"5ft 7in",
                         @"5ft 8in",
                         @"5ft 9in",
                         @"5ft 10in",
                         @"5ft 11in",
                         @"6ft 1in",
                         @"6ft 2in",
                         @"6ft 3in",
                         @"6ft 4in",
                         @"6ft 5in",
                         @"6ft 6in",
                         @"6ft 7in",
                         @"6ft 8in",
                         nil];

weightsArray = [NSArray arrayWithObjects:
                     @"100",
                     @"110",
                     @"120",
                     @"130",
                     @"140",
                     @"150",
                     @"160",
                     @"170",
                     @"180",
                     @"190",
                     @"200",
                     @"210",
                     @"220",
                     @"230",
                     @"240",
                     @"250",
                     @"260",
                     nil];


timeArray = [NSArray arrayWithObjects:
             @"1",
             @"2",
             @"3",
             @"4",
             @"5",
             @"6",
             nil];
}



- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)personInfoPicker
{
    return 3;
}


- (NSInteger)pickerView:(UIPickerView *)personInfoPicker numberOfRowsInComponent: (NSInteger)component
{
    if (component == 0) 
        return [heightsArray count];
    else if (component == 1)
        return [weightsArray count];
    else
        return [timeArray count];
}

- (NSString *)pickerview:(UIPickerView *)personInfoPicker titleForRow:(NSInteger)row forComponent:(NSInteger)component
{    
    if (component == 0)
        return [heightsArray objectAtIndex:row];
    else if (component == 1)
        return [weightsArray objectAtIndex:row];
    else
        return [timeArray objectAtIndex:row];
}
@end
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7 answers

You need to set the picker view dataSourceand call it reloadAllComponentsafter filling the arrays.

self.personInfoPicker.delegate = self;
self.personInfoPicker.dataSource = self;
[self.personInfoPicker reloadAllComponents];
+18
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arrarys init.

+2

.

`NSMutableArray *_month_ary=[[NSMutableArray alloc]initWithObjects:@"01",@"02",@"03",@"04",@"05",@"06",@"07",@"08",@"09",@"10",@"11",@"12", nil];
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView;
{
    return 1;
}

-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{


    if ([pickerView isEqual:_month_picker_view]) {
        return [_month_ary count];
    }
    return 0;
}
-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{


    if ([pickerView isEqual:_month_picker_view])
    {
        return [_month_ary objectAtIndex:row];
    }
    return nil;
}
-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{


    if ([pickerView isEqual:_month_picker_view]) {
        _Pay_Month_txt.text=[_month_ary objectAtIndex:row];
        deal_cridit_card_month_str = [_month_ary objectAtIndex:row];
    }
}`
+2

. "pickerView" .

- (NSInteger)pickerView:(UIPickerView *)personInfoPicker numberOfRowsInComponent: (NSInteger)component


- (NSInteger)pickerView:(UIPickerView *)thePickerView numberOfRowsInComponent: (NSInteger)component


- (NSInteger)pickerView:(UIPickerView *)personInfoPicker numberOfRowsInComponent: (NSInteger)component


- (NSInteger)pickerView:(UIPickerView *)thePickerView numberOfRowsInComponent: (NSInteger)component

personInfoPicker PickerView, .h, PickerView.

, .

.

+1

i , , datasource delegate, uipickerview, viewdidload reload pickerview,

+1

.

- (NSString *)pickerview:(UIPickerView *)personInfoPicker titleForRow:(NSInteger)row forComponent:(NSInteger)component


- (NSString *)pickerview:(UIPickerView *)personInfoPicker titleForRow:(NSInteger)row forComponent:(NSInteger)component

If you write pickerview, it will declare a new method in your class that will never be called. So simple, but still :-)

+1
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I think you did not allocate an array used as a collector data source, for example,

 NSMutableArray *_month_ary=[[NSMutableArray alloc]initWithObjects:@"01",@"02",@"03",@"04",@"05",@"06",@"07",@"08",@"09",@"10",@"11",@"12", nil];
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