Swift 未在UIImageView中渲染图像

由下面的函数生成的此图像拒绝显示在UIImageView中

这是iOS问题还是生成映像时出错

多谢各位

private func plotLogGraph(_ samples: [CGFloat], maximumValue max: CGFloat, zeroValue min: CGFloat, imageHeight: CGFloat,color:UIColor) -> UIImage? {
    let imageSize = CGSize(width: CGFloat(samples.count), height: imageHeight)
    UIGraphicsBeginImageContext(imageSize)
    guard let context = UIGraphicsGetCurrentContext() else {
        return nil
    }

    context.setAlpha(1.0)
    context.setLineWidth(1.0)
    context.setStrokeColor(color.cgColor)

    let sampleDrawingScale: CGFloat
    if max == min {
        sampleDrawingScale = 0
    } else {
        sampleDrawingScale = imageHeight / 2 / (max - min)
    }
    let verticalMiddle = imageHeight / 2
    for (x, sample) in samples.enumerated() {
        let height = (sample - min) * sampleDrawingScale
        context.move(to: CGPoint(x: CGFloat(x), y: verticalMiddle - height))
        context.addLine(to: CGPoint(x: CGFloat(x), y: verticalMiddle + height))
        context.strokePath();
    }
    guard let image = UIGraphicsGetImageFromCurrentImageContext() else {
        return nil;
    }

    UIGraphicsEndImageContext()
    return image;
}

---

渲染示例只是显示图像的全屏图像视图，请参见

---

它拒绝显示在imageview中是什么意思？dropbox中的图像在ImageView中工作正常显示代码。显示如何将图像指定给imageView等。渲染示例仅为显示图像的全屏imageView，请参阅