Question

Here is my code

class.h

.......
{
  NSInteger selectedRow;
}
@property (nonatomic) NSInteger selectedRow;
.......

classs.m

 @synthesize selectedRow = _selectedRow;
    .......
UIPickerView *picker = [[UIPickerView alloc] initWithFrame:CGRectMake(20, 150, 280, 100)];
picker.delegate = self;
picker.showsSelectionIndicator = YES;
[self.view addSubview:picker];

self.selectedRow =  [picker selectedRowInComponent:0];

When a button is pressed selector dog is called

-(void)dbg
{
  NSLog(@"%d", self.selectedRow) -- RESULT 0
  NSLOg(@"%@", self.selectedRow) -- RESULT null
}

What I miss here ?

Answer 1

NSLog(@"%@", …)prints objects, but NSInteger is a primitive type. The first NSLog should work correctly.

You have to implement the picker’s delegate, especially pickerView:didSelectRow:inComponent:

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
    self.selectedRow = row;
}