I just found that the solution is: diceImageView1?.image = Image Literal because diceImageView1 is already a UIImageView This is my first experience with optionals in Swift. Thank you.

Thank you for your suggestion; I will give it a try. I am following a course on learning Swift (I'm new to it); and the answer the teacher of the course is here: Xcode view controller - https://gist.github.com/angelabauer/9d94ee98153b84681a63e7744077c9f0 Have there been changes made to Swift and/or Xcode since she posted her solution?