Question

Hello Guys actually i have a lot of UIView custom class objects as a subview of a UIViewController class view which is inside a UIScrollView. And i want to check colors of UIView custom class objects. code i use is given below:-

    - (void) RectColorCheck:(id)sender
{
    NSArray *subViews = [[NSArray alloc] init];
    subViews = [self.scrollView subviews];
    NSLog(@"array----%@",subViews);

        for (viewCG in subViews) 
        {
            if ([viewCG.backgroundColor isEqual: [UIColor darkGrayColor]])
            {
                [viewCG setBackgroundColor:[UIColor orangeColor]];
            }
        }
}

but it not works the subview array of viewCG is null.
And the below code which adds the custom class(UIView) objects in viewCG subviews:-

for (int i=0; i<[mapDataArr count]; i++)
    {
        X = [[[mapDataArr objectAtIndex:i] valueForKey:@"X"] intValue];
        Y = [[[mapDataArr objectAtIndex:i] valueForKey:@"Y"] intValue];
        W = [[[mapDataArr objectAtIndex:i] valueForKey:@"W"] intValue];
        H = [[[mapDataArr objectAtIndex:i] valueForKey:@"H"] intValue];

        circleVwObj = [[CircleView alloc] init];
        circleVwObj.frame = CGRectMake(X,Y, W, H);
        circleVwObj.tag = i;

        circleVwObj.lbl.frame = CGRectMake(2,2, circleVwObj.frame.size.width, circleVwObj.frame.size.height/2);
        circleVwObj.lbl.text = [[mapDataArr objectAtIndex:i] valueForKey:@"standId"];
        NSLog(@"lbl text---%@", circleVwObj.lbl.text);
        circleVwObj.lbl.font = [UIFont boldSystemFontOfSize:11];
        circleVwObj.lbl.backgroundColor = [UIColor clearColor];
        circleVwObj.lbl.textColor = [UIColor whiteColor];
        circleVwObj.lbl.textAlignment = UITextAlignmentCenter;
        circleVwObj.lbl.minimumFontSize = 11;
        circleVwObj.lbl.adjustsFontSizeToFitWidth = YES;
        circleVwObj.lbl.autoresizingMask = (UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight);

        [self.viewCG addSubview:circleVwObj];
    }

Answer 1

If the subviews array is nil, it is very likely that self.viewCG is nil as well and hasn’t been initialized.

Also, you should use isEqual: to compare colors. The == operator just compares pointer identity (which might actually give you the expected result in this particular case, but it’s likely to break).