swift - swift 中 forEach 循环的进度条

Question

如何测量 forEach 循环的进度并将其显示在进度栏中？我将旋转垂直图像使其水平。每次要转换的图像数量都会不同。

这是我正在做的转换图像的工作正常，我只需要一种向用户显示进度的方法:

func rotateandSave(files: [URL]) {
    files.forEach { file in
        let path = file
        let image = NSImage(contentsOf: path)
        let rotatedImage = image?.rotated(by: rotateAngle)
        saveImage(image: rotatedImage!, destination: path)
    }
}

Answer 1

这样做:

func rotateandSave(files: [URL]) {
DispatchQueue.global(qos: .utility).async {
    files.forEach { file in
        let path = file
        let image = NSImage(contentsOf: path)
        let rotatedImage = image?.imageRotated(by: 90)
        saveImage(image: rotatedImage!, destination: path)
        DispatchQueue.main.async {
            self.progressBar.increment(by: 1)
        }
    }
}