【发布时间】:2019-09-07 15:59:58
【问题描述】:
在呈现 UIImagePickerController 时,我在“UIImageView”上使用了正常的点击手势。但我不知道为什么从照片库中挑选的图像总是质量很差(模糊、裁剪等)。从相机中挑选时,图像非常好。
这里是这个自定义视图类的完整代码。
class ImageEditingView: UIView {
let imageView = UIImageView()
weak var delegate: ViewController!
var croppingRect: CGRect?
var croppedRect: CGRect?
var ratioWidth: CGFloat? {
didSet {
self.setNeedsDisplay()
}
}
var ratioHeight: CGFloat? {
didSet {
self.setNeedsDisplay()
}
}
// Only override draw() if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
override func draw(_ rect: CGRect) {
super.draw(rect)
// Drawing code
let padding: CGFloat = 20
self.imageView.frame = CGRect(center: rect.midPoint, size: rect.size - padding)
self.imageView.contentMode = .scaleAspectFill
self.imageView.clipsToBounds = true
self.imageView.isUserInteractionEnabled = true
self.imageView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(openImagePickerConroller)))
self.addSubview(imageView)
if let imageWidth = ratioWidth, let imageHeight = ratioHeight {
if imageWidth > imageHeight {
let newImageHeight = imageHeight/imageWidth * (rect.size.width - (2 * padding))
let yForCroppedRect = (self.bounds.size.height - newImageHeight)/2
self.croppingRect = CGRect(x: padding, y: yForCroppedRect, width: rect.size.width - (2 * padding), height: newImageHeight)
} else if imageWidth < imageHeight {
let newImageWidth = imageWidth/imageHeight * (rect.size.height - (2 * padding))
let xForCroppedRect = (self.bounds.size.width - newImageWidth)/2
self.croppingRect = CGRect(x: xForCroppedRect, y: padding, width: newImageWidth, height: rect.size.height - (2 * padding))
} else {
self.croppingRect = nil
}
}
let bigRect = CGRect(x: 0, y: 0, width: self.bounds.width, height: self.bounds.height)
let smallRect = self.croppingRect ?? self.imageView.frame
self.croppedRect = smallRect
let pathBigRect = UIBezierPath(rect: bigRect)
let pathSmallRect = UIBezierPath(rect: smallRect)
pathBigRect.append(pathSmallRect)
pathBigRect.usesEvenOddFillRule = true
let fillLayer = CAShapeLayer()
fillLayer.path = pathBigRect.cgPath
fillLayer.fillRule = CAShapeLayerFillRule.evenOdd
fillLayer.fillColor = UIColor.darkGray.cgColor
//fillLayer.opacity = 0.4
self.layer.addSublayer(fillLayer)
}
@objc func openImagePickerConroller() {
let imagePicker = UIImagePickerController()
imagePicker.sourceType = .photoLibrary//.camera
imagePicker.delegate = self
self.delegate.present(imagePicker, animated: true, completion: nil)
}
}
extension ImageEditingView: UIImagePickerControllerDelegate, UINavigationControllerDelegate {
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
if let pickedImage = info[.originalImage] as? UIImage {
self.imageView.image = pickedImage
self.ratioWidth = 10
self.ratioHeight = 10
self.delegate.dismiss(animated: true, completion: nil)
}
}
func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
self.delegate.dismiss(animated: true, completion: nil)
}
}
extension CGRect {
init(center: CGPoint, size: CGSize) {
let origin = CGPoint(x: center.x - (size.width/2), y: center.y - (size.height/2))
self.init(origin: origin, size: size)
}
var midPoint: CGPoint {
return CGPoint(x: self.midX, y: self.midY)
}
}
extension CGSize {
static func -(size: CGSize, diff: CGFloat) -> CGSize {
let dim = size.width <= size.height ? size.width : size.height
return CGSize(width: dim - diff, height: dim - diff)
}
}
【问题讨论】:
-
您选择的图片是从高分辨率照片库中选择的吗?
-
请向我们展示您的代码。
-
是的,它们是高分辨率图像
-
比例是干什么用的?
ratioWidth和ratioHeight。如果你把它注释掉会发生什么? -
如果我把这些注释掉也没有用。如上图所示,我在 UIImage 周围绘制了一个深灰色层。真的没有影响。但是,如果您仍然想知道我在上面分享了完整的代码。
标签: ios swift uiimagepickercontroller