Second ScrollView doesn't zoom or scroll - ios

Question

I have two Scroll View's in a xib, and they both contain a very large image that should start with it completely scaled down to fit. The first ScrollView works perfectly, objects are all moving around correctly when you zoom or scroll, but the second ScrollView starts completely zoomed in, unable to zoom out.
The ScrollView is now showing 25% of the image(completely zoomed in at 0,0) and also cannot be dragged to see the rest. If I pinch to zoom, the image moves diagonally up and left without zooming at all, I can now drag the image back to 0,0 and back down the the max point it scrolled diagonally.
.h file
UIScrollView *_scrollView;
UIScrollView *_miamiScrollView;
UIView *_mapImageView;
UIView *_mapMiamiView;
UIView *_mapContentView;
NSArray *_autoLayoutViews;
NSArray *_staticViews;
#property (strong, nonatomic) IBOutlet UIScrollView *scrollView;//(linked to working scrollview)
#property (strong, nonatomic) IBOutlet UIScrollView *miamiScrollView;//(Linked to 'broken' scrollview)
.m file
- (void)viewDidLoad
{
[self _customizeViews];
}
- (void) _customizeViews
{
UIImageView *mapImageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"MainGameDisplay.jpg"]];
mapImageView.userInteractionEnabled = YES;
UIImageView *mapMiamiView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"miami.jpg"]];
mapMiamiView.userInteractionEnabled = YES;
_mapContentView = [[UIView alloc] initWithFrame:CGRectMake(0, 50, 568, 270)];
_mapContentView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
_mapContentView.clipsToBounds = YES;
_mapContentView.userInteractionEnabled = YES;
[_mapContentView addSubview:_scrollView];
[_mapContentView addSubview:_miamiScrollView];
[self.view addSubview:_mapContentView];
[self.view sendSubviewToBack:_mapContentView];
UIScrollView *scrollView = _scrollView;
CGRect scrollFrame = scrollView.frame;
scrollFrame.origin = CGPointZero;
scrollView.frame = scrollFrame;
scrollView.delegate = self;
scrollView.minimumZoomScale = 1;
scrollView.maximumZoomScale = 1.0;
[scrollView addSubview:mapImageView];
scrollView.contentSize = mapImageView.frame.size;
_scrollView = scrollView;
_mapImageView = mapImageView;
UIScrollView *miamiScrollView = _miamiScrollView;
CGRect miamiScrollFrame = CGRectMake(0 , 270, 568, 270);
scrollFrame.origin = CGPointZero;
miamiScrollView.frame = miamiScrollFrame;
miamiScrollView.delegate = self;
miamiScrollView.minimumZoomScale = 0.125;
miamiScrollView.maximumZoomScale = 1;
[miamiScrollView addSubview:mapMiamiView];
miamiScrollView.contentSize = mapMiamiView.frame.size;
_miamiScrollView = miamiScrollView;
_mapMiamiView = mapMiamiView;
[self _setupAutolayoutViews];
[self _setupStaticViews];
[self _zoomToFit: _scrollView];
[self _zoomToFit: _miamiScrollView];
[self _updatePositionForViews:_autoLayoutViews];
}
- (void) _zoomToFit: (UIScrollView*)view
{
CGFloat contentWidth = view.contentSize.width;
CGFloat contentHeigth = view.contentSize.height;
CGFloat viewWidth = view.frame.size.width;
CGFloat viewHeight = view.frame.size.height;
CGFloat width = viewWidth / contentWidth;
CGFloat heigth = viewHeight / contentHeigth;
CGFloat scale = MAX(width, heigth);
if ( scale < view.minimumZoomScale ) {
view.minimumZoomScale = scale;
} else if ( scale > view.maximumZoomScale ) {
view.maximumZoomScale = scale;
}
view.zoomScale = scale;
}
#pragma mark - Positions
- (void) _updatePositionForViews:(NSArray *)views
{
CGFloat scale = _scrollView.zoomScale;
CGPoint contentOffset = _scrollView.contentOffset;
contentOffset.x -= _scrollView.frame.origin.x;
contentOffset.y -= _scrollView.frame.origin.y;
for ( UIView *view in views ) {
CGPoint basePosition = [self _basePositionForView:view];
[self _updatePositionForView:view scale:scale basePosition:basePosition offset:contentOffset];
}
}
- (CGPoint) _basePositionForView:(UIView *)view
{
NSString *key = [NSString stringWithFormat:#"%d", view.tag];
NSString *stringValue = [_coordinates objectForKey:key];
NSArray *values = [stringValue componentsSeparatedByString:#":"];
if ( [values count] < 2 ) return CGPointZero;
CGPoint result = CGPointMake([[values objectAtIndex:0] floatValue], [[values objectAtIndex:1] floatValue]);
return result;
}
- (void) _updatePositionForView:(UIView *)view scale:(CGFloat)scale basePosition:(CGPoint)basePosition offset:(CGPoint)offset;
{
CGPoint position;
position.x = (basePosition.x * scale) - offset.x;
position.y = (basePosition.y * scale) - offset.y;
CGRect frame = view.frame;
frame.origin = position;
view.frame = frame;
}
//////////////////////////////////////////////////////////////////////////////////////
#pragma mark - UIScrollViewDelegate
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView;
{
[self _lockInteraction];
}
- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate;
{
[self _unlockInteraction];
}
- (void)scrollViewWillBeginZooming:(UIScrollView *)scrollView withView:(UIView *)view
{
[self _lockInteraction];
}
- (void)scrollViewDidEndZooming:(UIScrollView *)scrollView withView:(UIView *)view atScale:(float)scale;
{
[self _unlockInteraction];
}
- (void) _lockInteraction
{
[self _setControls:_staticViews interacted:NO];
[self _setControls:_autoLayoutViews interacted:NO];
}
- (void) _unlockInteraction
{
[self _setControls:_staticViews interacted:YES];
[self _setControls:_autoLayoutViews interacted:YES];
}
- (void) _setControls:(NSArray *)controls interacted:(BOOL)interacted
{
for ( UIControl *control in controls ) {
if ( [control isKindOfClass:[UIControl class]]) {
control.userInteractionEnabled = interacted;
}
}
}
- (void)scrollViewDidZoom:(UIScrollView *)scrollView
{
[self _updatePositionForViews:_autoLayoutViews];
}
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
[self _updatePositionForViews:_autoLayoutViews];
}
- (UIView *) viewForZoomingInScrollView:(UIScrollView *)scrollView;
{
return _mapImageView;
}
//DEFAULT BUTTONS.
- (void) _setupAutolayoutViews
{
UIButton *btn1 = [UIButton buttonWithType: UIButtonTypeDetailDisclosure];
[btn1 addTarget:self action:#selector(quickTest:) forControlEvents:UIControlEventTouchUpInside];
btn1.tag = kAddContactButton;
btn1.center = CGPointZero;
[_mapContentView addSubview:btn1];
_autoLayoutViews = [[NSArray alloc] initWithObjects:btn1, nil];
}
//CUSTOM BUTTONS.
- (void) _setupStaticViews
{
UIButton *openMiamiButton = [UIButton buttonWithType:UIButtonTypeCustom];
[openMiamiButton setBackgroundImage:[UIImage imageNamed:#"logo.png"] forState:UIControlStateNormal];
[openMiamiButton addTarget:self action:#selector(quickTest:) forControlEvents:UIControlEventTouchUpInside];
openMiamiButton.frame = CGRectMake(0.0 ,0.0, 50.0, 50.0);
openMiamiButton.tag = OpenMiamiButton;
openMiamiButton.enabled = YES;
openMiamiButton.alpha = 0.5;
[_mapImageView addSubview:openMiamiButton];
_staticViews = #[openMiamiButton,];
for ( UIView *view in _staticViews ) {
CGPoint point = [self _basePositionForView:view];
CGRect frame = view.frame;
frame.origin = point;
view.frame = frame;
}
}
//And for the transition between views:
-(void) quickTest: (UIButton *)button
{
/*
if (!openMiami)
openMiami = [[MiamiGameDisplay alloc] initWithNibName:nil bundle:nil];
openMiami.mainPage = self;
[self.navigationController pushViewController:openMiami animated:YES];
*/
if (!testBool){
[UIView animateWithDuration:0.5f
animations:^{
_scrollView.frame = CGRectMake(0 , -270, 568, 270);
}
completion:Nil];
[UIView animateWithDuration:0.5f
animations:^{
_miamiScrollView.frame = CGRectMake(0 , 0, 568, 270);
}
completion:Nil];
testBool=YES;
}
else {
[UIView animateWithDuration:0.5f
animations:^{
_miamiScrollView.frame = CGRectMake(0 , 270, 568, 270);
}
completion:Nil];
[UIView animateWithDuration:0.5f
animations:^{
_scrollView.frame = CGRectMake(0 , 0, 568, 270);
}
completion:Nil];
testBool=NO;
}
}

Answer 1

I've run into a similar issue with scrollViews. Basically, as far as I can tell, only the last scrollView added to the window will respond as a scrollView.
You can produce the same effect with any other type of object being added to the window before the scrollView.
Example :
[[self window] addSubview:logo];
[[self window] addSubview:scrollView];
Will work, but:
[[self window] addSubview:scrollView];
[[self window] addSubview:logo];
will not. (Currently running against iOS 6.1.2 and xCode 4.6.1)