iOS滚动视图默认缩放图像大小

Question

I have a scrollview that contains an image and it is able to zoom the image. I want the default zoom size to contain the whole image for any image that I attach to it. I don't know how to do this.

Here is the code I currently have so far:

UIImage *image = [UIImage imageNamed:@"cat.jpg"];

self.imageView = [UIImageView new];
self.imageView.image = image;
[self.imageView sizeToFit];

self.scroll = [[UIScrollView alloc] initWithFrame:self.view.bounds];
self.scroll.contentSize = image.size;
self.scroll.delegate = self;
self.scroll.minimumZoomScale = 0.2;
self.scroll.maximumZoomScale = 1.0;
self.scroll.zoomScale = 0.2;

[self.scroll addSubview:self.imageView];

[self.view addSubview:self.scroll];

Answer 1

So it sounds like you want the images to 'fit' the scroll view. I hope thats correct. If so, try the code below.

UIImageView *tempImageView = [[[UIImageView alloc] initWithImage:[UIImage imageNamed:@"Watson.jpg"]] autorelease];
tempImageView.frame = scrollView.bounds;
self.imageView = tempImageView;

scrollView.backgroundColor = [UIColor blackColor];
scrollView.minimumZoomScale = 1.0  ;
scrollView.maximumZoomScale = imageView.image.size.width / scrollView.frame.size.width;
scrollView.zoomScale = 1.0;
scrollView.delegate = self;

[scrollView addSubview:imageView];

That code will fit your image to the screen. So it will not be zoomed when you start.

Answer 2

If I understand you correctly you need a method that you could use to display any image as you wish. You'd need something like this:

-(void)setImageOnScrollView:(UIImage*)image {

self.imageView.image = image;
[self.imageView sizeToFit];

self.scroll.contentSize = image.size;
self.scroll.delegate = self;
self.scroll.minimumZoomScale = 0.2;
self.scroll.maximumZoomScale = 1.0;
self.scroll.zoomScale = 0.2;

[self.scroll addSubview:self.imageView];
[self.view addSubview:self.scroll];

}

And you can call this method like so:

self.scroll = [[UIScrollView alloc] initWithFrame:self.view.bounds];
UIImage *image = [UIImage imageNamed:@"cat.jpg"];
[self setImageOnScrollView:image];