ios - 如何在 Swift 中正确旋转 CATextLayer？

Question

我目前面临一个问题，即旋转 CATextLayer 时，框架大小会同时意外转换。我希望文本可以旋转某个角度而不改变其框架大小。如果有人能启发我，请提前致谢。

我尝试过的:

var someAngle: CGFloat = 0 {
    didSet {
        drawText()
    }
}

func drawText() {

    for layer in someView.layer.sublayers ?? [] where layer is CATextLayer {
        layer.removeFromSuperlayer()
    }

    let textLayer = CATextLayer()
    textLayer.fontSize = 26
    textLayer.backgroundColor = UIColor.lightGray.cgColor
    textLayer.string = "Hello world"
    textLayer.alignmentMode = .center

    textLayer.anchorPoint = CGPoint(x: 0.5, y: 0.5)
    textLayer.transform = CATransform3DMakeRotation(someAngle, 0.0, 0.0, 1.0)

    let textSize = calculateTextSize(text: "Hello world", font: UIFont.systemFont(ofSize: 26))
    let origin = CGPoint(x: someView.bounds.midX - textSize.width/2, y: someView.bounds.midY - textSize.height/2)
    textLayer.frame = CGRect(origin: origin, size: textSize)

    someView.layer.addSublayer(textLayer)
}

但是，结果如下所示:

我的期望与此类似:

Answer 1

通过在函数外部添加 textLayer 属性解决了这个问题。

var textLayer = CATextLayer()