How to zoom image to fullscreen mode? - iphone

Question

I have paging UIScrollView with images. I want to implement animated zooming of image to fullscreen on some gesture. And another animation to zoom image back to scroll view. Like in Photos app on iPad or like videos in Safari.
Of course it would not be UIImageView. It would be some wrapper class with image inside. The main question is how to present fullscreen view. Is it must be modal view or not.
Any help is appreciated.

Answer 1

Check on touching the image
if it is small convert into full size.
if it is large convert into small size.
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
if (isLarge) [self makeSmall];
else [self makeFull];
}
- (void)makeFull {
[[self superview] bringSubviewToFront:self];
isLarge = YES;
CGRect largeFrame = [self superview].bounds;
original = self.frame;
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.5];
[self setFrame:largeFrame];
[internal setFrame:self.bounds];
[UIView commitAnimations];
}
- (void)makeSmall {
isLarge = NO;
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.5];
[self setFrame:original];
[internal setFrame:self.bounds];
[UIView commitAnimations];
}

Answer 2

I found a solution to this that involves both gesture recognizers and animated transitions. You remove the scrollview and add the fullscreen image. Then reverse that to return to the just the scrollview.
Use the frame of the window to determine size for the new UIImage.
The types of gesture recognizers can be adjusted to suit your needs!
-(void)viewDidLoad
{
[super viewDidLoad];
UITapGestureRecognizer *tapTwice = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tapTwice:)];
tapTwice.numberOfTapsRequired = 2;
[self.imageView addGestureRecognizer:tapTwice];
}
- (void)tapOnce:(id)tapOnce {
[UIView transitionWithView:self.view
duration:0.7
options:UIViewAnimationOptionTransitionCrossDissolve
animations:^ {
[self.fullScreenImage removeFromSuperview];
}
completion:nil];
}
- (void)tapTwice:(id)tapTwice {
if(self.fullScreenImage == nil){
self.fullScreenImage = [[UIImageView alloc] initWithFrame:self.view.window.frame];
UITapGestureRecognizer *tapOnce = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tapOnce:)];
tapOnce.numberOfTapsRequired = 1;
[tapOnce requireGestureRecognizerToFail:tapTwice];
[self.fullScreenImage addGestureRecognizer:tapOnce];
[self.fullScreenImage setUserInteractionEnabled:YES];
//self.fullScreenImage = [load your image here]
}
[UIView transitionWithView:self.view.window
duration:0.7
options:UIViewAnimationOptionTransitionCrossDissolve
animations:^ {
[self.view.window addSubview:self.fullScreenImage];
}
completion:nil];
}

Answer 3

Download this sample for Image gallery sample code and get through it. It would definitely helps you to understand how to implement your idea.

Answer 4

Like below you can use for zooming the image view.
UIView * viewForScroll;
UIImageView *imgviewForScroll;
UIScrollView *scrollToRead = [[UIScrollViewalloc]initWithFrame:CGRectMake(175, 5, 300, 311)];
scrollToRead.backgroundColor = [UIColordarkGrayColor];
scrollToRead.showsHorizontalScrollIndicator = YES;
scrollToRead.delegate = self;
[scrollToRead setContentSize:CGRectMake(0, 0, 300, 400).size];
scrollToRead.maximumZoomScale = 2;
scrollToRead.minimumZoomScale = 1;
[self.view addSubview:scrollToRead];
[scrollToRead release];
viewForScroll = [[UIViewalloc]initWithFrame:CGRectMake(0,0,300,400)];
[scrollToRead addSubview:viewForScroll];
[viewForScroll release];
imgviewForScroll = [[UIImageViewalloc]initWithFrame:CGRectMake(0,0,300,400)];
imgviewForScroll.image = [UIImageimageWithContentsOfFile:[arrayComicContentobjectAtIndex:0]];
[viewForScroll addSubview:imgviewForScroll];
[imgviewForScroll release];
//=========UIScrollView Delegate methods
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
return viewForScroll;
}
Like to know if you need any further clarifications