how to resize UIScrollview dynamically - iphone

Question

well i working with to zoom image with UIScrollview..my UIScrollview size is fix so whenever i make a zoom of a image then it goes cut..i wanna do that as i zoom the image the UIScrollview also increse height and width as per image zoom..
any suggetions will be appreciated......

Answer 1

This should work :-)
Make a UIImage
Make a UIImageView holding the image
Put the UIImageView into a UIScrollView
Set the contentSize of the UIScrollView to the size of the UIImage
Remember to return the UIimageView in viewForZoomingInScrollView
Put this into your .h file:
UIImageView *imageView;
#property (nonatomic, retain) UIImageView *imageView;
And remember to synthesize and release imageView
Put this where you want to make your scroll view:
UIImage *image = [UIImage imageNamed:#"myImage.jpg"];
imageView = [[UIImageView alloc] initWithImage:image];
[imageView setFrame:CGRectMake(0, 0, image.size.width, image.size.height)];
UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
[scrollView setMinimumZoomScale:0.5];
[scrollView setMaximumZoomScale:3.0];
[scrollView setContentSize:CGSizeMake(image.size.width, image.size.height)];
[scrollView setDelegate:self];
[scrollView addSubview:imageView];
[[self view] addSubview:scrollView];
[scrollView release];
Add the UIScrollView delegate method
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
return imageView;
}
UPDATE:
I misunderstood the question when adding the above solution. This should do it :-)
kScrollViewAddSize is a constant which defines the amount to add to the UIScrollView's size.
In your .h file you should add the following:
UIImageView *imageView;
UIScrollView *scrollView;
Remember to synthesize and release them.
- (void)viewDidLoad
{
[super viewDidLoad];
UIImage *image = [UIImage imageNamed:#"apple.jpg"];
imageView = [[UIImageView alloc] initWithImage:image];
[imageView setFrame:CGRectMake(kScrollViewAddSize / 2, kScrollViewAddSize / 2, image.size.width, image.size.height)];
int width = imageView.frame.size.width + kScrollViewAddSize;
int height = imageView.frame.size.height + kScrollViewAddSize;
scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake((self.view.frame.size.width - width) / 2, (self.view.frame.size.height - height) / 2, width, height)];
[scrollView setMinimumZoomScale:0.5];
[scrollView setMaximumZoomScale:3.0];
[scrollView setBackgroundColor:[UIColor redColor]];
[scrollView setContentSize:CGSizeMake(image.size.width, image.size.height)];
[scrollView setDelegate:self];
[scrollView addSubview:imageView];
[[self view] addSubview:scrollView];
}
- (void)scrollViewDidZoom:(UIScrollView *)_scrollView {
int width = imageView.frame.size.width + kScrollViewAddSize;
int height = imageView.frame.size.height + kScrollViewAddSize;
[scrollView setFrame:CGRectMake((self.view.frame.size.width - width) / 2, (self.view.frame.size.height - height) / 2, imageView.frame.size.width + kScrollViewAddSize, imageView.frame.size.height + kScrollViewAddSize)];
}
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)_scrollView {
return imageView;
}
Add the parth in viewDidLoad where you want to create your UIScrollView and add the two delegate methods.