我遇到了捏缩放问题UIImageView
它设置在UIScrollView
。图像会根据用户的捏点输入进行缩放,但图像会变大并变大,直到占据整个屏幕,而不是停留在我的UIScrollView
的范围内。我看了一堆不同的SO问题,文章和YouTube视频,试图找到问题的根源,但一直未能找到任何东西。Swift - UIImageView的缩放比UIScrollView的大
下SO问题似乎是松散的联系,但我还是不能看着他们之后解决我的问题:
- content size of UIScrollView
-
- UIScrollView squashes UIImageView image
- Swift UIImageView Stretched Aspect
- UIImageView pinch zoom swift
我的故事板中创建了我的UIScrollView
,我使用在界面生成器中创建的布局约束将其固定到位。我在viewDidLoad()
中将滚动视图的代理设置为self(并且已将UIScrollViewDelegate
添加到我的课程顶部)。 UIImageView
以编程方式创建。我宣布图像视图在类如下面的顶部:
class VCImageViewer: UIViewController, UIScrollViewDelegate {
@IBOutlet weak var lblImageTitle: UILabel!
@IBOutlet weak var btnBack: UIButton!
@IBOutlet weak var scrollView: UIScrollView!
var imageView:UIImageView = UIImageView() // <-- Image view
我然后在viewDidLoad()
添加图像视图作为我UIScrollView
子视图与代码的后续行,叫:
self.scrollView.addSubview(self.imageView)
将图像视图添加到滚动视图后,我将图像加载到图像视图中。我从URL中获取图像,并使用以下代码加载它。再次,这在viewDidLoad()
中被调用。
self.imageView.image = UIImage(data: data)
self.imageView.frame = CGRect(origin: CGPoint(x: 0, y: 0), size: (self.imageView.image?.size)!)
if self.imageView.image != nil {
self.lblError.isHidden = true
self.FormatImageViewerWithImage()
}
这确认图像已正确加载,隐藏着一个警告标签,如果它没有我将显示,并调用self.FormatImageViewerWithImage()
,低于:
func FormatImageViewerWithImage() {
// Constraints
let constraintImageViewTop:NSLayoutConstraint = NSLayoutConstraint(item: self.imageView, attribute: NSLayoutAttribute.top, relatedBy: NSLayoutRelation.equal, toItem: self.scrollView, attribute: NSLayoutAttribute.top, multiplier: 1, constant: 0)
let constraintImageViewBottom:NSLayoutConstraint = NSLayoutConstraint(item: self.imageView, attribute: NSLayoutAttribute.bottom, relatedBy: NSLayoutRelation.equal, toItem: self.scrollView, attribute: NSLayoutAttribute.bottom, multiplier: 1, constant: 0)
let constraintImageViewLeft:NSLayoutConstraint = NSLayoutConstraint(item: self.imageView, attribute: NSLayoutAttribute.left, relatedBy: NSLayoutRelation.equal, toItem: self.scrollView, attribute: NSLayoutAttribute.left, multiplier: 1, constant: 0)
let constraintImageViewRight:NSLayoutConstraint = NSLayoutConstraint(item: self.imageView, attribute: NSLayoutAttribute.right, relatedBy: NSLayoutRelation.equal, toItem: self.scrollView, attribute: NSLayoutAttribute.right, multiplier: 1, constant: 0)
self.view.addConstraints([constraintImageViewTop, constraintImageViewBottom, constraintImageViewLeft, constraintImageViewRight])
self.scrollView.contentSize = self.imageView.image!.size
self.scrollView.clipsToBounds = false
let scrollViewFrame = scrollView.frame
let scaleWidth = scrollViewFrame.size.width/self.scrollView.contentSize.width
let scaleHeight = scrollViewFrame.size.height/self.scrollView.contentSize.height
let minScale = min(scaleWidth, scaleHeight)
self.scrollView.minimumZoomScale = minScale
self.scrollView.maximumZoomScale = 1.0
self.scrollView.zoomScale = minScale
}
我也与实施scrollViewDidZoom
:
func scrollViewDidZoom(_ scrollView: UIScrollView) {
self.CentreScrollViewContents()
}
func CentreScrollViewContents() {
let boundsSize = self.scrollView.bounds.size
var contentsFrame = self.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
}
self.imageView.frame = contentsFrame
}
和viewForZooming
用:
func viewForZooming(in scrollView: UIScrollView) -> UIView? {
return self.imageView
}
我已经看过以前的问题(包括上面列出的一些问题),建议将代码添加到viewWillLayoutSubviews()
,但是我还没有取得任何成功,所以我的viewWillLayoutSubviews()
是空的。
任何人都可以看到我做错了什么吗?
更改this:self.scrollView.clipsToBounds = false此self.scrollView.clipsToBounds = true –
@MohammadBashirSidani Legend!非常感谢你,我正在为此而撕心裂肺。如果您想将其添加为答案,我会为您接受。 –
非常高兴它的工作!我将添加它作为答案,谢谢! –