UIScrollView ContentSize height too large

Question

I have a UIScrollView that should only scroll horizontally. The scroll view is pinned to the bottom of the screen. I have set auto layout constraints to a fixed height. I set the contentSize to a fixed size.

However, when I run the application the content is showing half of it off the bottom of the screen. And it will scroll vertically for what seems to be about 200 pixels.

I have a map and a label pinned above the scroll view and the layout looks exactly as I want, except the content of the scroll view seems off. This is the code I've written:

in my .h file:

@interface MapViewController : UIViewController <UIScrollViewDelegate>

in viewDidLoad:

self.scrollView.delegate = self;
[self.scrollView setContentSize:CGSizeMake(600, 100)];

// add some content
UIView *personView = [[UIView alloc] initWithFrame:CGRectMake(0, 8, 100, self.scrollView.frame.size.height-16)];
personView.backgroundColor = [UIColor cyanColor];

UIView *personView2 = [[UIView alloc] initWithFrame:CGRectMake(110, 8, 100, self.scrollView.frame.size.height-16)];
personView2.backgroundColor = [UIColor redColor];

UIView *personView3 = [[UIView alloc] initWithFrame:CGRectMake(220, 8, 100, self.scrollView.frame.size.height-16)];
personView3.backgroundColor = [UIColor blueColor];

UIView *personView4 = [[UIView alloc] initWithFrame:CGRectMake(330, 8, 100, self.scrollView.frame.size.height-16)];
personView4.backgroundColor = [UIColor orangeColor];

[self.scrollView addSubview:personView];
[self.scrollView addSubview:personView2];
[self.scrollView addSubview:personView3];
[self.scrollView addSubview:personView4];

I don't use UIScrollView that often, so am I missing something? Does anyone know where the sizing problem could be coming from?

Also I did an NSLog on the frame height and contentSize height and both equal 100.

Edit:

This view is in a navigation controller and I set the navigation bar from hidden = YES to hidden = NO on first load. I've noticed that the content height is different when I leave it hidden, so this must have something to do with it.

If you're using constraints, you should not set the contentSize. You should use constraints to control contentSize. Read Technical Note TN2154: UIScrollView And Autolayout. — rob mayoff
@robmayoff is there a way to work around using constraints for contentSize, seems like theres an easier solution. Also you left out panama at the end of your palindrome on your bio :) — MSU_Bulldog

Hanny Hanny · Accepted Answer · 2015-10-26T19:27:29

Try to set your scrollView's Content size int "viewDidLayoutSubviews" method with keeping the autolayouts set.

-(void)viewDidLayoutSubviews
{
  [self.scrollView setContentSize:CGSizeMake(required_width, required_height)];
}

Check the Navigation Bar set to the ViewController in the Storyboard as well. If there is any, try removing it.

And please lemme know if you still face some problem.

UIScrollView ContentSize height too large

1 Answers