最佳答案
When I try creating a button and setting a background image in Swift:
let button = UIButton.buttonWithType(UIButtonType.System) as UIButton
button.frame = CGRectMake(100, 100, 100, 100)
button.setImage(IMAGE, forState: UIControlState.Normal)
button.addTarget(self, action: "btnTouched:", forControlEvents: UIControlEvents.TouchUpInside)
self.view.addSubview(button)
I always get an error: "Cannot convert the expression's type 'Void' to type 'UIImage'".