objective-c - Strange behaviour when laying out subviews

Question

I am creating a UI that the user can page through multiple views by using a UIScrollView. I create the UIView objects in code and add them to UIScrollView. I use the code below to create the views.

CGRect frame;
frame.origin.x = self.scrollView.frame.size.width * i;
frame.origin.y = 0;
frame.size = self.scrollView.frame.size;

UIView *brandView = [[UIView alloc] initWithFrame:frame];

UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0.0, 50.0, frame.size.width, 30)];
label.text = [brand objectForKey:@"name"];
label.textAlignment = UITextAlignmentCenter;
label.backgroundColor = [UIColor redColor];
[brandView addSubview:label];

UIImageView *logoImageView = [[UIImageView alloc] init];
logoImageView.frame = CGRectMake(20.0, 100.0, 280.0, 300.0);
[brandView addSubview:logoImageView];
logoImageView.file = [brand objectForKey:@"logo"];
[logoImageView loadInBackground];

Although I give 50.0 for the y coordinate for the label, I can't see the label at all when I run the app. And logoImageView has 100.0 for its top but it appears just below the status bar, as if it had 0.0 for it's y coordinate.

What is the reason for this strange behaviour, am I doing something wrong?

Note: Auto layout for the UIScrollView is disabled on IB.

Answer 1

下面的代码将为您工作！

CGRect frame;
frame.origin.x = self.scrollView.frame.size.width * 10;
frame.origin.y = 0;
frame.size = self.scrollView.frame.size;

UIView *brandView = [[UIView alloc] init]; // CHANGE THAT HAS TO BE DONE

UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0.0, 50.0, self.scrollView.frame.size.width, 30)];
label.text = @"Test";
label.textAlignment = UITextAlignmentCenter; // DEPRECATED IN iOS 6.0
label.backgroundColor = [UIColor redColor];
[brandView addSubview:label];
[self.scrollView addSubview:brandView];