UIScrollView can zoom, but cant pan - ios

Question

I have a UIScrollView with a UIView inside it, in side the UIView I made a button to add textLabels to it.
and ideally I would want a really big canvas and be able to put text on it and pan and zoom around. however with the UIScrollView it does zoom, but does not pan at all
It seems that when I remove the UIView that i add inside the UIScrollView it works fine.
heres viewDidLoad:
[super viewDidLoad];
CGFloat mainViewWidth = 700;
CGFloat mainViewHeight = 500;
//scrollView.contentSize = CGSizeMake(scrollView.frame.size.width * kNumberOfPages, scrollView.frame.size.height * kNumberOfPages);
//self.mainScrollView.bounds = CGRectMake(0., 0., 3000, 3000);
self.mainScrollView.scrollsToTop = NO;
self.mainScrollView.delegate = self;
self.mainScrollView.maximumZoomScale = 50.;
self.mainScrollView.minimumZoomScale = .1;
self.mainScrollView.autoresizingMask = UIViewAutoresizingFlexibleHeight;
self.mainView = [[UIView alloc] initWithFrame: CGRectMake(0, 0, mainViewWidth, mainViewHeight)];
[self.mainView setUserInteractionEnabled:NO];
self.mainView.backgroundColor = [[UIColor alloc] initWithRed:0.82110049709463495
green:1
blue:0.95704295882687884
alpha:1];
[self.mainScrollView setContentSize:CGSizeMake(5000, 5000)];
[self.mainScrollView insertSubview:self.mainView atIndex:0];
Edit:
Heres the all I have for UIScrollViewDelegate
#pragma mark - Scroll View Delegate
- (void)scrollViewDidScroll:(UIScrollView *)sender {
}
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
//
return self.mainView;
}
- (void)scrollViewDidEndZooming:(UIScrollView *)zoomedScrollView withView:(UIView *)view atScale:(float)scale
{
}

Answer 1

I just went through this exact same dilemma.
My UIScrollView exists within the storyboard, and if I add a UIView (containerView) within that storyboard to the UIScrollView, the image fails to pan. And all sorts of other centering weirdness occurs too.
But if I do it through code:
// Set up the image we want to scroll & zoom
UIImage *image = [UIImage imageNamed:#"plan-150ppi.jpg"];
self.imageView = [[UIImageView alloc] initWithImage:image];
self.containerView = [[UIView alloc] initWithFrame:self.imageView.frame];
[self.containerView addSubview:self.imageView];
[self.scrollView addSubview:self.containerView];
// Tell the scroll view the size of the contents
self.scrollView.contentSize = self.containerView.frame.size;
... then it works just fine.