Swift 3 GCFloat to GCRect - swift3

Question

I'm using this code piece in my Swift project.
The following code worked fine in Swift 2 but don't seem to work in Swift 3 anymore, it gives the following error:
Cannot assign value of type '(CGFloat, CGFloat, Int, Int)' to type 'CGRect'
if plusLayer == nil {
plusLayer = CALayer()
let halfWidth: CGFloat = self.bounds.size.width / 2
let halfHeight: CGFloat = self.bounds.size.height / 2
let ds: CGFloat = sqrt(halfWidth * halfWidth / 2)
let x: CGFloat = halfWidth + ds - 27 / 2
let y: CGFloat = halfHeight - ds - 27 / 2
plusLayer.frame = (x, y, 27, 27)
plusLayer.contentsGravity = kCAGravityResizeAspectFill
if let i = plusSignImage {
plusLayer.contents = i.cgImage
} else {
plusSignImage = UIImage(named: "PlusSign", in: Bundle(for: self.dynamicType), compatibleWith: UITraitCollection(displayScale: UIScreen.main().scale))
plusLayer.contents = plusSignImage!.cgImage
}
layer.addSublayer(plusLayer)
}
Anyone knows how I can solve this issue? Help'd be really appreciated!
Thanks! :D

Answer 1

This line plusLayer.frame = (x, y, 27, 27)
should be
plusLayer.frame = (x, y, 27 as CGFloat, 27 as CGFloat)
This is because the CGRect initializer expects 4 numbers with the same type. Take a look at the Xcode suggestions:

Answer 2

You need explicit casting of 27 (an Int type) to CGFloat:
plusLayer.frame = (x, y, 27 as CGFloat, 27 as CGFloat)

Answer 3

as an old developer, let make some clearness:
a) casting is a powerful features of some languages, but it must be known in details
b) we can cast using "as", but is NOT the same as doing CGFloat(xx)
c) "as" must be used for type casting of objects.
(see:
https://developer.apple.com/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/TypeCasting.html
)
d) CGRectMake does work in swift 2.x/xcode 7.3
e) don't cast to double, simply use:
let r = CGRect(x: 10, y: 20, width: 30, height: 40)
compiler will understand which of these method call:
public init(x: CGFloat, y: CGFloat, width: CGFloat, height: CGFloat)
public init(x: Double, y: Double, width: Double, height: Double)
public init(x: Int, y: Int, width: Int, height: Int)
and will call the 3rd.
If You write:
let d = 10.0
let r2 = CGRect(x: d, y: 20, width: 30, height: 40)
it will call 2nd, as d is a Double.
my two cents.