UIImageView inside a scrollView with screen rotation - objective-c

Question

Its been 2 days working on this problem and i just can't figure it out.
I have a UIScrollView stretched in all my view and i am adding to it as subViews a random number of UIImageViews, and i am enabling paging so it will look like a gallery app.
My problem is when i rotate the screen, the images frames stays the same (this is probably because of the constraints) so i tried to give the images constraints and it worked they would rotate perfectly but then a problem appeared where the scroll view wont scroll anymore and the images are on top of each other ..
This is my code :
-(void)setupScrollView
{
for(int i = 0 ; i < [_arrayOfImages count] ; i++)
{
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(self.view.frame.size.width*i, 0, self.view.frame.size.width, self.view.frame.size.height)];
[imageView setImage:[[_arrayOfImages objectAtIndex:i] getImageForImageView:imageView]];
[imageView setUserInteractionEnabled:YES];
[imageView setContentMode:UIViewContentModeScaleAspectFit];
[imageView setTranslatesAutoresizingMaskIntoConstraints:NO];
[_scrollView addSubview:imageView];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeLeading multiplier:1.f constant:0.f]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeTrailing multiplier:1.f constant:0.f]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeTop multiplier:1.f constant:0.f]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeBottom multiplier:1.f constant:0.f]];
}
[_scrollView setContentSize:CGSizeMake(self.view.frame.size.width*[_arrayOfImages count], self.view.frame.size.height)];
}
Can anyone help me please ? thanks

Answer 1

You need to change the frame of UIScrollView and the UIImageViews in Autorotate delegate methods. After that you have to change the ContentSize of UIScrollView.
- (BOOL) shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientat‌​ion{}
//ios 7
-(void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrient‌​ation{}
duration:(NSTimeInterval)duration -
-(void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOri‌​entation{}
//ios 8
-(void)viewWillTransitionToSize:(CGSize)size
withTransitionCoordinator:(id<UIViewControllerTransitionCoordinator>)coordinator{
if (size.width > size.height) {
// Positions for Landscape
} else {
// Positions for Portrait
}
}

Answer 2

I'am not really sure, because I need to see all application, but you can try following code
-(void)setupScrollView
{
for(int i = 0 ; i < [_arrayOfImages count] ; i++)
{
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(self.view.frame.size.width*i, 0, self.view.frame.size.width, self.view.frame.size.height)];
[imageView setImage:[[_arrayOfImages objectAtIndex:i] getImageForImageView:imageView]];
[imageView setUserInteractionEnabled:YES];
[imageView setContentMode:UIViewContentModeScaleAspectFit];
[imageView setTranslatesAutoresizingMaskIntoConstraints:NO];
[_scrollView addSubview:imageView];
[imageViewArray addObject:imageView]
if (i == 0) {
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeLeading multiplier:1.f constant:0.f]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeTrailing multiplier:1.f constant:0.f]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeTop multiplier:1.f constant:0.f]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeBottom multiplier:1.f constant:0.f]];
} else {
UIImageView * previousView = [imageViewArray objectAtIndex:i-1];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:previousView attribute:NSLayoutAttributeLeading multiplier:1.f constant:0.f]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:previousView attribute:NSLayoutAttributeTrailing multiplier:1.f constant:0.f]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:previousView attribute:NSLayoutAttributeTop multiplier:1.f constant:0.f]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:imageView attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:previousView attribute:NSLayoutAttributeBottom multiplier:1.f constant:0.f]];
}
}
[_scrollView setContentSize:CGSizeMake(self.view.frame.size.width*[_arrayOfImages count], self.view.frame.size.height)];
}
Also, you need to declare imageViewArray as NSMutableArray:
add to #interface:
NSMutableArray * imageViewArray;
and in viewDidLoad:
imageViewArray = [[NSMutableArray alloc] init];