斯威夫特:从中心
问题描述:
我一直在做一个简单的UIBezierPath
动画与斯威夫特UIBezierPath中风动画。该路径包括创建带有彩色边框的圆角矩形。动画必须是彩色边框的图形。要做到这一点,我创建了UIBezierPath(roundedRect:, cornerRadius:)
斯威夫特:从中心
let layer = CAShapeLayer()
var viewPrueba = UIView()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
viewPrueba = UIView(frame: CGRectMake(self.view.frame.width/2-100, self.view.frame.height/2 - 100, 200, 200))
self.view.addSubview(viewPrueba)
let path = UIBezierPath(roundedRect: CGRectMake(0, 0, 200, 200), cornerRadius: 40.0)
layer.path = path.CGPath
layer.fillColor = UIColor.clearColor().CGColor
layer.strokeColor = UIColor.blueColor().CGColor
layer.strokeStart = 0.0
layer.strokeEnd = 0.0
layer.lineWidth = 4.0
layer.lineJoin = kCALineJoinRound
viewPrueba.layer.addSublayer(layer)
let tapGR = UITapGestureRecognizer(target: self, action: #selector(ViewController.anim))
self.view.addGestureRecognizer(tapGR)
}
func anim() {
let anim1 = CABasicAnimation(keyPath: "strokeEnd")
anim1.fromValue = 0.0
anim1.toValue = 1.0
anim1.duration = 4.0
anim1.repeatCount = 0
anim1.autoreverses = false
anim1.removedOnCompletion = false
anim1.additive = true
anim1.fillMode = kCAFillModeForwards
self.layer.addAnimation(anim1, forKey: "strokeEnd")
}`
它运作良好,一个CAShapeLayer
。唯一的问题是,动画从顶部中心广场的左上部分,而不是开始。我怎样才能做到这一点?
我在为了实现这一发现的唯一的事情就是用一个圆圈,而不是一个矩形,这不是我们想要做的事情吧。
由于
答
CoreAnimate动画作为所述的UIBezierPath绘制的顺序相同。
系统方法
+ (instancetype)bezierPathWithRoundedRect:(CGRect)rect cornerRadius:(CGFloat)cornerRadius;
回报这是从左上方,让您的动画从左上角开始绘制的UIBezierPath。
但你可以创建自己的UIBezierPath绘制表格顶部中心:
func centerStartBezierPath(frame:CGRect,cornerRadius:CGFloat) -> UIBezierPath {
let path = UIBezierPath()
path.moveToPoint(CGPointMake(frame.width/2.0, 0))
path.addLineToPoint(CGPointMake(frame.width-cornerRadius, 0))
path.addArcWithCenter(CGPointMake(frame.width-cornerRadius, cornerRadius),
radius: cornerRadius,
startAngle: CGFloat(-M_PI/2),
endAngle: 0,
clockwise: true)
path.addLineToPoint(CGPointMake(frame.width, frame.height-cornerRadius))
path.addArcWithCenter(CGPointMake(frame.width-cornerRadius, frame.height-cornerRadius),
radius: cornerRadius,
startAngle: 0,
endAngle: CGFloat(M_PI/2),
clockwise: true)
path.addLineToPoint(CGPointMake(cornerRadius, frame.height))
path.addArcWithCenter(CGPointMake(cornerRadius, frame.height-cornerRadius),
radius: cornerRadius,
startAngle: CGFloat(M_PI/2),
endAngle: CGFloat(M_PI),
clockwise: true)
path.addLineToPoint(CGPointMake(0, cornerRadius))
path.addArcWithCenter(CGPointMake(cornerRadius, cornerRadius),
radius: cornerRadius,
startAngle: CGFloat(M_PI),
endAngle: CGFloat(M_PI*3/2),
clockwise: true)
path.closePath()
path.applyTransform(CGAffineTransformMakeTranslation(frame.origin.x, frame.origin.y))
return path;
}
作品般的魅力!谢谢! :) – rulilg