Question

I have two columns pickerView. In first column i have units like km, feet. I want to set different values for both like km 1,2,3 and for feet 100, 2000, 300. Now I did following code. I declare two arrays unitArray and distanceArray in viewDidLoad method.

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

-(NSString *)pickerView:(UIPickerView *)thePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component{

if (component == UNIT)
       return [unitArray objectAtIndex:row];
else
       return [distanceArray objectAtIndex:row];
}

- (void)pickerView:(UIPickerView *)thePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {

        distanceRow = [distancePicker selectedRowInComponent:DISTANCE];
        unitRow = [distancePicker selectedRowInComponent:UNIT];

        dist = [distanceArray objectAtIndex:distanceRow];
        unit = [unitArray objectAtIndex:unitRow];

        txtIBOutletDistance.text =[NSString stringWithFormat:@"%@ %@",dist,unit];
}

After doing this code i am showing same values for both km and feet i.e km and feet in one column and 1,2,3 in second column. I want after selecting km values should be 1,2,3 and for feet selection values should be 100,200,300. If any one knows how to do it please help me. I will appreciate him/her.

Answer 1

You should change the value of distanceArray in pickerView:didSelectRow:inComponent according to the selected UNIT as below:

- (void)pickerView:(UIPickerView *)thePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
    if(component == UNIT) {
        unit = [unitArray objectAtIndex:row]; //unit is a property of the interface
        if([unit IsEqualToString:@"km"] {
            distanceArray = [NSArray arrayWithObject:@"1", @"2", @"3", nil];
        } else if([unit IsEqualToString:@"feet"] {
            distanceArray = [NSArray arrayWithObject:@"100", @"200", @"300", nil];
        }
    } else {
        dist = [distanceArray objectAtIndex:row];
        txtIBOutletDistance.text =[NSString stringWithFormat:@"%@ %@",dist,unit]; 
    }
}