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iphone - How to change color of selected row in UIPickerView

Ok, maybe I'm missing something really simple and I apologize if that's the case, however, I've googled every permutation of the title and have not found! So this is simply what I want to do: change the background color of the label I'm using as the row view in a 2 component pickerview when that row has been selected. So I thought this would work:

if (row == [pickerview selectedRowForComponent])
    viewlabel.backgroundColor = redcolor;

but this doesn't work. It seems to arbitrarily choose which row to color and sometimes even give a bad access error. I've tried all different clauses to no effect! ANy suggestions would be greatly appreciated!!

Here's the full method:

- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view
{

    if (component == kNumberComponent) {


#define PICKER_LABEL_FONT_SIZE 24
#define PICKER_LABEL_ALPHA 1.0
        // UIFont *font = [UIFont boldSystemFontOfSize:PICKER_LABEL_FONT_SIZE];
        UIFont *font = [ UIFont fontWithName:@"AppleGothic"  size:24];
        UILabel *carsLabel =[ [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 75, 50) ]autorelease];
        //[picker selectRow:row inComponent:component animated:YES];
        NSString *pickerText = [self.numbers objectAtIndex:(int)row];
        carsLabel.text = pickerText;
        carsLabel.textAlignment = UITextAlignmentCenter;
        NSLog(@"carsLabel = %@",carsLabel.text);
        //carsLabel.text = @"maybe because the string isn't long enough";
        carsLabel.textColor = [UIColor blackColor];
        carsLabel.font = font;





        carsLabel.opaque = YES;


        [view addSubview:carsLabel];

        return carsLabel;   
    } else {
        UIFont *font = [ UIFont fontWithName:@"AppleGothic"  size:18];

        UILabel *carsLabel = [[[UILabel alloc] initWithFrame:CGRectMake(0, 0, 225, 50)] autorelease];
        id fact = [self.facts objectAtIndex:(int)row];
        NSString *pickerText = @"Dictionary Entry";
        if ( [fact isKindOfClass:[NSString class]]) {


            pickerText = [self.facts objectAtIndex:(int)row];

        } 
        carsLabel.text = pickerText;
        carsLabel.textAlignment = UITextAlignmentCenter;
        NSLog(@"carsLabel = %@",carsLabel.text);
        //carsLabel.text = @"maybe because the string isn't long enough";
        carsLabel.textColor = [UIColor blackColor];
        carsLabel.font = font;
        if ( row == 0) {
        carsLabel.backgroundColor = [UIColor redColor];

        }
        //carsLabel.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"blackboard.png"]];;
        carsLabel.opaque = YES;

        [view addSubview:carsLabel];

        return carsLabel;
    }


    return nil;
}
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1 Answer

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by (71.8m points)

Normally, I use this method:

I use the custom view for show the row item

-(UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view
{

    UILabel *label = (id)view;

    if (!label)
    {

        label= [[UILabel alloc] initWithFrame:CGRectMake(0.0f, 0.0f, [pickerView rowSizeForComponent:component].width, [pickerView rowSizeForComponent:component].height)];
        label.textAlignment = NSTextAlignmentCenter;
        label.textColor = [UIColor whiteColor];
        label.text = _arrayStringPicker[row];

    }  

    return label;

I change color of row selected with:

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

    UILabel *labelSelected = (UILabel*)[pickerView viewForRow:row forComponent:component];
    [labelSelected setTextColor:[UIColor redColor]];

}

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