如何将文本置于圆圈中间?

时间:2015-08-12 16:49:00

标签: ios swift uilabel calayer uibezierpath

我做了一个圆圈课,但我想把文字放在它的直接中心。

字体大小无关紧要,文字应始终显示在中心。

到目前为止,我只是尝试了任意值,直到它足够接近中心。必须有一个更简单的方法。

import UIKit


class CircleView: UIView {
let circleLayer: CAShapeLayer  = CAShapeLayer()

init(frame: CGRect, innerColor: CGColor = Colors.colorWithHexString("#858585").CGColor, rimColor: CGColor = UIColor.blueColor().CGColor) {
    super.init(frame: frame)
    self.backgroundColor = UIColor.clearColor()
    let circlePath = UIBezierPath(arcCenter: CGPoint(x: frame.size.width / 2.0, y: frame.size.height / 2.0), radius: (frame.size.width - 10)/2, startAngle: 0.0, endAngle: CGFloat(M_PI * 2.0), clockwise: true)

    // Setup the CAShapeLayer
    circleLayer.path = circlePath.CGPath
    circleLayer.fillColor = innerColor
    circleLayer.strokeColor = rimColor
    circleLayer.lineWidth = 5.0

    // Don't draw the circle at start
    circleLayer.strokeEnd = 1.0
    layer.addSublayer(circleLayer)
}

func animateCircle(duration: NSTimeInterval) {
    let animation = CABasicAnimation(keyPath: "strokeEnd")

    animation.duration = duration

    animation.fromValue = 0
    animation.toValue = 1

    // Do a linear animation 
    animation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionLinear)

    circleLayer.strokeEnd = 1.0

    // Do the actual animation
    circleLayer.addAnimation(animation, forKey: "animateCircle")
}

required init(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
}
}

1 个答案:

答案 0 :(得分:3)

假设您的视图中有一个名为UILabel的{​​{1}}属性;您可以使用label方法将center值设置为视图的中心位置:

layoutSubviews

请注意,使用override func layoutSubviews() { super.layoutSubviews() label.sizeToFit() label.center = self.convertPoint(self.center, fromView: self.superview) } 可以轻松实现这一点,但您无法像上面那样更改任何框架或中心:

Auto Layout