Swift 3.0 中的 CGAffineTransformScale

Question

Swift 3.0 没有名为 CGAffineTransformScale 的方法。

func didPinchGesture(pinchRecognizer : UIPinchGestureRecognizer) {
  if let view = pinchRecognizer.view {
    view.transform = CGAffineTransformScale(view.transform,
                            recognizer.scale, recognizer.scale)
    pinchRecognizer.scale = 1
  }
}

scaleBy 不会自动完成但添加到 CGAffineTransform scaleBy 会抛出错误，因为 scale 不再是 CGAffineTransform 的 属性： CGAffineTransform.scaledBy(view.transform, pinchRecognizer.scale, pinchRecognizer.scale).

使用 Swift 3.0 配置捏合手势识别器的最佳方法是什么？

Answer 1

在Swift, CGAffineTransformScale is imported as an instance method on the CGAffineTransform struct, called scaledBy(x:y:):

view.transform = view.transform.scaledBy(x: recognizer.scale, y: recognizer.scale)

Answer 2

您可以像这样在 Swift 3 中使用缩放变换：

if let view = pinchRecognizer.view {
    view.transform = CGAffineTransform(scaleX: recognizer.scale, y: recognizer.scale)
    ...
  }