'ContentMode' is not a member type of 'UIView'

问题

I have the following piece of code which works well for a legacy IOS app, but now no longer works in xcode 9:

The error I'm getting is:

'ContentMode' is not a member type of 'UIView'

Here is the code:

import Foundation

struct ImageViewLayout {
    static func frameForImageWithSize(_ image: CGSize, previousFrame: CGRect, inContainerWithSize container: CGSize, usingContentMode contentMode: UIView.ContentMode) -> CGRect {
        let size = sizeForImage(image, previousSize: previousFrame.size, container: container, contentMode: contentMode)
        let position = positionForImage(size, previousPosition: previousFrame.origin, container: container, contentMode: contentMode)

        return CGRect(origin: position, size: size)
    }

回答1:

The enum type name UIView.ContentMode is new in Swift 4.2, introduced in Xcode 10. Before that (e.g. Xcode 9, as you say) it was UIViewContentMode.

来源：https://stackoverflow.com/questions/52416192/contentmode-is-not-a-member-type-of-uiview