通过更改帧调整UIImageView的大小

我在序列图像板中添加了一个带有默认图像的UIImageView。在代码中,我在运行时更新图像并调整帧。

mainImageView.sd_setImage(with: NSURL(string: urlString) as URL?, completed: {
        (image, error, cacheType, url) in
        self.setPoints()
    })

public func setPoints() {
    mainImageView.frame = CGRect(x:x, y:0, width:(mainImageView.image?.size.width)!/1.7, height:(mainImageView.image?.size.height)!/1.7)
    mainImageView.contentMode = .scaleAspectFill
    mainImageView.setNeedsDisplay()
    mainImageView.reloadInputViews()
    mainImageView.updateConstraintsIfNeeded()
}