Star Rating in Swift

Question

So I needed a a star rating feature to appear in my app - it doesn't need to be interactive.

I have my app connected to a database I've set up in Parse, and I've made a column for OurRatingof type Number, and I just set a number between 0.5 and 5.

In my custom cell, I have 5 images which will display my star images. The code I've done is as follows:

//I define my images at the top
var fullStarImage: UIImage = UIImage(named: "starFull.png")!
var halfStarImage: UIImage = UIImage(named: "starHalf.png")!
var emptyStar: UIImage = UIImage(named: "starEmpty.png")!

Then further down in my table method, I have:

//Star Rating System
 if let ourRating = object?["OurRating"] as? Double {
 if ourRating == 0.5 {
 cell?.star1.image = halfStarImage
 }
 if ourRating == 1 {
 cell?.star1.image = fullStarImage
 }
 if ourRating == 1.5 {
 cell?.star1.image = fullStarImage
 cell?.star2.image = halfStarImage
 }
 if ourRating == 2 {
 cell?.star1.image = fullStarImage
 cell?.star2.image = fullStarImage
 }
 if ourRating == 2.5 {
 cell?.star1.image = fullStarImage
 cell?.star2.image = fullStarImage
 cell?.star3.image = halfStarImage
 }
 if ourRating == 3 {
 cell?.star1.image = fullStarImage
 cell?.star2.image = fullStarImage
 cell?.star3.image = fullStarImage
 }
 if ourRating == 3.5 {
 cell?.star1.image = fullStarImage
 cell?.star2.image = fullStarImage
 cell?.star3.image = fullStarImage
 cell?.star4.image = halfStarImage
 }
 if ourRating == 4 {
 cell?.star1.image = fullStarImage
 cell?.star2.image = fullStarImage
 cell?.star3.image = fullStarImage
 cell?.star4.image = fullStarImage
 }
 if ourRating == 4.5 {
 cell?.star1.image = fullStarImage
 cell?.star2.image = fullStarImage
 cell?.star3.image = fullStarImage
 cell?.star4.image = fullStarImage
 cell?.star5.image = halfStarImage
 }
 if ourRating == 5 {
 cell?.star1.image = fullStarImage
 cell?.star2.image = fullStarImage
 cell?.star3.image = fullStarImage
 cell?.star4.image = fullStarImage
 cell?.star5.image = fullStarImage
 }
}

This code WORKS! Nothing wrong with what it produces, I'm using wondering if there was a better way I could have written this? Maybe to reduce the amount of code?

Any advice is appreciated.

Answer 1

You could create a helper routine getStarImage:forRating: and use that to set up each star:

let fullStarImage: UIImage = UIImage(named: "starFull.png")!
let halfStarImage: UIImage = UIImage(named: "starHalf.png")!
let emptyStarImage: UIImage = UIImage(named: "starEmpty.png")!
func getStarImage(starNumber: Double, forRating rating: Double) -> UIImage {
 if rating >= starNumber {
 return fullStarImage
 } else if rating + 0.5 == starNumber {
 return halfStarImage
 } else {
 return emptyStarImage
 }
}
if let ourRating = object?["OurRating"] as? Double {
 cell?.star1.image = getStarImage(1, forRating: ourRating)
 cell?.star2.image = getStarImage(2, forRating: ourRating)
 cell?.star3.image = getStarImage(3, forRating: ourRating)
 cell?.star4.image = getStarImage(4, forRating: ourRating)
 cell?.star5.image = getStarImage(5, forRating: ourRating)
}

---

If the last part looks a bit redundant, you could do it in a loop. This probably isn't worth it for 5 items, but it demonstrates what you can do in Swift:

for (index, imageView) in [cell?.star1, cell?.star2, cell?.star3, cell?.star4, cell?.star5].enumerate() {
 imageView?.image = getStarImage(index + 1, forRating: ourRating)
}

• Nick89: This looks a lot cleaner. I will give this a try and let you know how I get on :) thanks I'll be sure to answer it right once I've tried.