>我真的很难在网上找到教程以及已经回答的问题(我已经尝试过了,但它们似乎不起作用(。我有一个UIImageView,我在我的视图的中心。我目前可以在屏幕上的任何位置点击并拖动它。我希望能够捏合以缩放和旋转此视图。我如何实现这一点?我已经尝试了下面的旋转代码,但它似乎不起作用?任何帮助都将是一个巨大的帮助,并标记为答案。谢谢你们。
import UIKit
class DraggableImage: UIImageView {
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
self.backgroundColor = .blue
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
self.backgroundColor = .green
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
if let touch = touches.first {
let position = touch.location(in: superview)
center = CGPoint(x: position.x, y: position.y)
}
}
}
class CVController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .white
let rotateGesture = UIRotationGestureRecognizer(target: self, action: #selector(rotateAction(sender:)))
firstImageView.addGestureRecognizer(rotateGesture)
setupViews()
}
func rotateAction(sender: UIRotationGestureRecognizer) {
let rotatePoint = sender.location(in: view)
let firstImageView = view.hitTest(rotatePoint, with: nil)
firstImageView?.transform = (firstImageView?.transform.rotated(by: sender.rotation))!
sender.rotation = 0
}
let firstImageView: DraggableImage = {
let iv = DraggableImage()
iv.backgroundColor = .red
iv.isUserInteractionEnabled = true
return iv
}()
func setupViews() {
view.addSubview(firstImageView)
let firstImageWidth: CGFloat = 50
let firstImageHeight: CGFloat = 50
firstImageView.frame = CGRect(x: (view.frame.width / 2) - firstImageWidth / 2, y: (view.frame.height / 2) - firstImageWidth / 2, width: firstImageWidth, height: firstImageHeight)
}
}
你的代码中有一些问题。首先,您需要将UIGestureRecognizerDelegate
添加到视图控制器,并使其成为手势识别器委托。您还需要实现shouldRecognizeSimultaneously
方法并返回true
。其次,在应用比例时,您需要在捏合开始时保存转换并在其顶部应用比例:
class DraggableImageView: UIImageView {
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
backgroundColor = .blue
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
backgroundColor = .green
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
if let position = touches.first?.location(in: superview){
center = position
}
}
}
<小时 /> class ViewController: UIViewController, UIGestureRecognizerDelegate {
var identity = CGAffineTransform.identity
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .white
setupViews()
let pinchGesture = UIPinchGestureRecognizer(target: self, action: #selector(scale))
let rotationGesture = UIRotationGestureRecognizer(target: self, action: #selector(rotate))
pinchGesture.delegate = self
rotationGesture.delegate = self
view.addGestureRecognizer(pinchGesture)
view.addGestureRecognizer(rotationGesture)
}
let firstImageView: DraggableImageView = {
let iv = DraggableImageView()
iv.backgroundColor = .red
iv.isUserInteractionEnabled = true
return iv
}()
func setupViews() {
view.addSubview(firstImageView)
let firstImageWidth: CGFloat = 50
let firstImageHeight: CGFloat = 50
firstImageView.frame = CGRect(x: view.frame.midX - firstImageWidth / 2, y: view.frame.midY - firstImageWidth / 2, width: firstImageWidth, height: firstImageHeight)
}
@objc func scale(_ gesture: UIPinchGestureRecognizer) {
switch gesture.state {
case .began:
identity = firstImageView.transform
case .changed,.ended:
firstImageView.transform = identity.scaledBy(x: gesture.scale, y: gesture.scale)
case .cancelled:
break
default:
break
}
}
@objc func rotate(_ gesture: UIRotationGestureRecognizer) {
firstImageView.transform = firstImageView.transform.rotated(by: gesture.rotation)
}
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
return true
}
}