How can I use UIScrollView for overlapped images iphone - iphone

Question

Hi, I have a big image and small image over it at a specific location...
I added them all under ScrollView, but it didn't work properly?
I want to zoom in, all together each in its place
Here is my code:
myScrollView.contentSize = CGSizeMake(imageView.frame.size.width, imageView.frame.size.height);
myScrollView.maximumZoomScale = 3.0;
myScrollView.minimumZoomScale = 1.0;
myScrollView.clipsToBounds = YES;
myScrollView.delegate = self;
[myScrollView addSubview:imageView];
thanks
Hi, mackworth; I did it, but if I didn't maximize the image, I can't move the scroll view anywhere, but if I zoomed it, I can see the rest.. I don't know why I tried changing it, but it work. Can you please look at the following code?
- (void)viewDidLoad{
[super viewDidLoad];
UIImage *image = [UIImage imageNamed:#"ucd.png"];
//creating a view for UCD image
ucdView = [[UIImageView alloc] initWithImage:image];
//setting the frame for the ucdView as the same size of ucd image
[ucdView setFrame:CGRectMake(0, 0, image.size.width, image.size.height)];
//for the red pin to display in specific loc
UIImageView *Health = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"redPin.png"]];
[Health setCenter:CGPointMake(310,135)];
//adding helathView to ucdview
[ucdView addSubview:Health];
//everything for scroll view
UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, ucdView.frame.size.width, ucdView.frame.size.height)];
[scrollView setMinimumZoomScale:1.0];
[scrollView setMaximumZoomScale:3.0];
scrollView.clipsToBounds = YES;
[scrollView setContentSize:CGSizeMake(image.size.width, image.size.height)];
[scrollView setDelegate:self];
[scrollView addSubview:ucdView];//adding ucd view to scroll view
[self.view addSubview:scrollView]; // adding scrollview to self.view main view
}
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {//apply zooming for scrollview
return scrollView;
}

Answer 1

Did you implement:
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
return self.imageView;
}
Also, you know that by setting the scrollView's contentSize to your imageSize, it can't grow any bigger than that, right? It'll zoom in place, cropping the outer pixels accordingly. As an aside, if that is your plan, why not just set it directly?
myScrollView.contentSize = imageView.frame.size;
=====Further answer, responding to additional source
Well, the main thing I notice is that you need to return the imageView ucdView in viewForZoomingInScrollView, not the scrollView. It looks like you already created ucdView as a property (so that it lives as long as your view does), but just in case...
1) In your .h file:
UIImageView * ucdView;
#property (nonatomic, retain) UIImageView * ucdView;
2) In your .m file;
#synthesize ucdView;
3) change your line:
ucdView = [[UIImageView alloc] initWithImage:image];
to just
self.ucdView = [[UIImageView alloc] initWithImage:image];
4) change the line
return scrollView
to:
return self.ucdView;
5) Add the following to your dealloc routine:
self.ucdView = nil;
Also, did you add <UIScrollViewDelegate> protocol to your ViewController definition (in .h file)?
Finally, you have a leak of scrollview and Health; add [scrollView release]; and [Health release] at end of viewDidLoad