Question

我正在尝试使用UIScrollview实现图像缩放功能。在哪里我保持图像适合方面。
图片位于UIScrollView内，图片框的类似于UIScrollView 这是我的代码。

class CroppingImageViewController: UIViewController, UIScrollViewDelegate{    
    var image:UIImage = UIImage()

    @IBOutlet var imageview:UIImageView!
    @IBOutlet var scrollview:UIScrollView!

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
        imageview.image = image
        scrollview.contentSize = imageview.frame.size;
        scrollview.minimumZoomScale = 1.0;
        scrollview.maximumZoomScale = 4.0;
        scrollview.setZoomScale(scrollview.minimumZoomScale, animated: true)
        scrollview.delegate = self;
    }

    func viewForZoomingInScrollView(scrollView: UIScrollView) -> UIView? {
        return imageview
    }
}

What's actually happening
What required
我的要求是图像应该滚动到它的内容。

Answer 1

self.automaticallyAdjustsScrollViewInsets=NO;

根据Apple文档，默认情况下，autoAdjustScrollViewInsets为YES。

所以它试图控制你的滚动视图。

在viewdidload方法中添加它，然后尝试。

Answer 2

我正在寻找相同的东西一段时间。而且我确实喜欢这个。它对我有用。

    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
        let image = info[UIImagePickerControllerOriginalImage] as! UIImage
        imageView.image = image

        imageView.contentMode = UIViewContentMode.center
        imageView.frame = CGRect(x: 0, y: 0, width: image.size.width, height: image.size.height)

        ScrollView.contentSize = imageView.frame.size

        let scrollViewFrame = ScrollView.frame
        let scaleWidth = scrollViewFrame.size.width / ScrollView.contentSize.width
        let scaleHeight = scrollViewFrame.size.height/ScrollView.contentSize.height

        let minScale = min(scaleHeight, scaleWidth)

        ScrollView.minimumZoomScale = minScale
        ScrollView.maximumZoomScale = 1
        ScrollView.zoomScale = minScale
        ScrollView.clipsToBounds = true

        centerScrollViewContents()

        picker.dismiss(animated: true, completion: nil)

    }

 func centerScrollViewContents(){
    let boundsSize = ScrollView.bounds.size
        var contentsFrame = imageView.frame

        if contentsFrame.size.width < boundsSize.width{
            contentsFrame.origin.x = (boundsSize.width - contentsFrame.size.width)/2

        }else{
            contentsFrame.origin.x = 0
        }

        if contentsFrame.size.height < boundsSize.height{
            contentsFrame.origin.y = (boundsSize.height - contentsFrame.size.height)/2
        }else{
            contentsFrame.origin.y = 0
        }

        imageView.frame = contentsFrame
    }

在UIScrollview上缩放图像后，它会滚动到图像区域之外

2 个答案: