前言
开发中总因为一些比较蛋疼的导角问题而困扰着我们,尤其是我们要给一个UIView导角成 左上 、左下。。。
这种需求很值得用代码实现一下, 今天突然在AppCode找到了一篇好文章.于是有了下文
通常导角
1
2
self.view.cornerRadius = 20.0
self.view.clipToBounds = true
这两行代码是全方向导角
如果像要搞成不同方向的话可以用iOS11 新的API和 iOS11以前的CAShapeLayer画贝赛尔曲线来解决
首先我们要创建一个UIView
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
class ViewController: UIViewController {
var cardView: UIView!
override func viewDidLoad() {
super.viewDidLoad()
cardView = UIView()
view.addSubview(cardView)
cardView.translatesAutoresizingMaskIntoConstraints = false
//把View居中
cardView.widthAnchor.constraint(equalToConstant: 200).isActive = true
cardView.heightAnchor.constraint(equalToConstant: 200).isActive = true
cardView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
cardView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
cardView.backgroundColor = UIColor(red: 1.0, green: 0.784, blue: 0.2, alpha: 1)
}
}
iOS11 以后苹果提供了一个UIView的属性叫maskedCorners用于CALayer的动画相关.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
public struct CACornerMask : OptionSet {
public init(rawValue: UInt)
public static var layerMinXMinYCorner: CACornerMask { get }
public static var layerMaxXMinYCorner: CACornerMask { get }
public static var layerMinXMaxYCorner: CACornerMask { get }
public static var layerMaxXMaxYCorner: CACornerMask { get }
}
下面我说一下
- layerMinXMinYCorner 底部右侧 的圆角 -> 右下角
- layerMaxXMinYCorner 顶部右侧 的圆角 -> 右上角
- layerMinXMaxYCorner 底部左侧 的圆角 -> 左下角
- layerMinXMinYCorner 顶部左侧 的圆角 -> 左上角
一般我们都为UIView写个 extension
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
extension UIView {
func roundCorners(cornerRadius: Double) {
self.layer.cornerRadius = CGFloat(cornerRadius)
self.clipsToBounds = true
if #available(iOS 11.0, *) {
self.layer.maskedCorners = [.layerMinXMinYCorner, .layerMaxXMinYCorner]
} else {
let path = UIBezierPath(roundedRect: self.bounds, byRoundingCorners: [.topLeft, .topRight], cornerRadii: CGSize(width: cornerRadius, height: cornerRadius))
let maskLayer = CAShapeLayer()
maskLayer.frame = self.bounds
maskLayer.path = path.cgPath
self.layer.mask = maskLayer
}
}
}
这里区分了iOS11之前和之后的两种搞法.
之前的话我们都是用一个贝塞尔曲线画path.然后创建CAShapeLayer 给self.layer.mask做一种透明的遮罩来解决不同方向导角问题.
添加动画效果的导角
我们在原ViewDidLoad()方法里面加个手势.
并写好触发的事件, 完整的代码如下
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
import UIKit
class ViewController: UIViewController {
var cardView: UIView!
override func viewDidLoad() {
super.viewDidLoad()
cardView = UIView()
view.addSubview(cardView)
cardView.translatesAutoresizingMaskIntoConstraints = false
cardView.widthAnchor.constraint(equalToConstant: 200).isActive = true
cardView.heightAnchor.constraint(equalToConstant: 200).isActive = true
cardView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
cardView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
cardView.backgroundColor = UIColor(red: 1.0, green: 0.784, blue: 0.2, alpha: 1)
let tapRecognizer = UITapGestureRecognizer(target: self, action: #selector(animateCornerChange(recognizer:)))
cardView.addGestureRecognizer(tapRecognizer)
}
@objc func animateCornerChange(recognizer: UITapGestureRecognizer) {
let targetRadius: Double = (cardView.layer.cornerRadius == 0.0) ? 100.0:0.0
if #available(iOS 10.0, *) {
UIViewPropertyAnimator(duration: 0.4, curve: .easeInOut) {
self.cardView.roundCorners(cornerRadius: targetRadius)
}.startAnimation()
} else {
UIView.animate(withDuration: 1.0, delay: 0.0, options: .curveEaseInOut, animations: {
}, completion: nil)
}
}
}
extension UIView {
func roundCorners(cornerRadius: Double) {
self.layer.cornerRadius = CGFloat(cornerRadius)
self.clipsToBounds = true
if #available(iOS 11.0, *) {
self.layer.maskedCorners = [.layerMinXMinYCorner, .layerMaxXMinYCorner]
} else {
let path = UIBezierPath(roundedRect: self.bounds, byRoundingCorners: [.topLeft, .topRight], cornerRadii: CGSize(width: cornerRadius, height: cornerRadius))
let maskLayer = CAShapeLayer()
maskLayer.frame = self.bounds
maskLayer.path = path.cgPath
self.layer.mask = maskLayer
}
}
}
这里主要强调一下动画的新API
iOS10之后U增加一个新的动画效果API
1
2
3
4
UIViewPropertyAnimator(duration: 0.4, curve: .easeInOut) {
//这里写相关View的操作代码 。。。eg:下面代码
self.cardView.roundCorners(cornerRadius: targetRadius)
}.startAnimation()
iOS之前可以通过古老的API来实现
1
2
3
4
UIView.animate(withDuration: 1.0, delay: 0.0, options: .curveEaseInOut, animations: {
//这里写相关View的操作代码 。。。eg:下面代码
self.cardView.roundCorners(cornerRadius: targetRadius)
}, completion: nil)
最终的效果
总结
iOS一些简单的动画导角比较常用所以记录下来,希望大家多多指教