Declaring a multi-type array - ios

Question

I would like to have my function return an array in which the first element is a String and the second is a UIImageView object. E.g.
["An example string", UIImageView()]
How do I tell the function that this will be returned in the section that follows the ->
So basically I want a function like this:
func DoSomething(num:Int) -> Array[String, UIImageView()] {
// Each of the following objects in the Array are UIImageView objects
Let imageViewObjects = [image1, image2, image3]
return [String(num), imageViewObjects[num]]
}
But the part I know I am getting wrong is the
Array[String, UIImageView]
P.S. I need to declare this because if I use [AnyObject] it will raise an error later on in the code basically saying that it cant manipulate an object of type AnyObject

Answer 1

Note that an Array is declared as [Int] or Array<Int> rather than Array[Int]. [Int] and Array<Int> are the same thing. You don't need to use both at once.
The easiest thing to do is use a tuple, declared like this:
(String, UIImageView)
I would use it like this (your code with corrections):
import UIKit
typealias StringView = (String, UIImageView)
// Returning an Optional to pass back that num may be out of range
// note that I'm using the typealias StringView here
func DoSomething(num:Int) -> StringView? {
let image1 = UIImageView()
let image2 = UIImageView()
let image3 = UIImageView()
let imageViewObjects = [image1, image2, image3]
// Need to check that num is a valid index
guard num < imageViewObjects.count else { return nil }
// return the tuple if num is valid
return (String(num), imageViewObjects[num])
}
Example usage:
if let returned = DoSomething(2) {
// printing the first item in returned tuple
print(returned.0)
}
// output: "2"
You can also use protocols to create a common protocol, add it to the classes in an extension, and then use the protocol in the declaration:
protocol Foo {}
extension String : Foo {}
extension UIImageView: Foo {}
var myArray:[Foo] ...
If you're going to use the returned value in a lot of places you might want to make it a full-blown struct or class:
import UIKit
struct StringView {
let string:String
let view:UIImageView
}
// Returning an Optional to pass back that num may be out of range
// note that I'm using the typealias StringView here
func DoSomething(num:Int) -> StringView? {
let imageViewObjects = [UIImageView(),
UIImageView(),
UIImageView()]
// Need to check that num is a valid index
guard num < imageViewObjects.count else { return nil }
// return the tuple if num is valid
return StringView(string: String(num), view: imageViewObjects[num])
}
if let returned = DoSomething(2) {
// printing the member "string" in the returned struct
print(returned.string)
}
// output: "2"
A tuple is usually the better choice unless you are using custom structs and classes.

Answer 2

You can use Dictionary objects in swift, here you can use key as your String and value as array of ImageView
let imageViewObjects = [image1, image2, image3]
let array : [String : UIImageView] = [
String(num) : imageViewObjects[num]
]
If you want to return only array you can do like this
let imageViewObjects = [image1, image2, image3]
var array : [AnyObject] = [AnyObject]()
array.append(String(num))
array.append(imageViewObjects[num])
In this you have to be sure that first object is a String and second is array of UIImageView