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iOS Build a Weather App with Swift Adding Weather Icons Streamlining Our Icon Enum

Britt Green
Britt Green
2,611 Points
Posted by Britt Green
Britt Green
2,611 Points

Is the Icon enum() portion superfluous?

If our Dark Sky API sends us the name of the icon, such as "clear-day", why do we convert that to .ClearDay in our enum, instead of just doing a switch statement that says case clear-day = "clear-day.png"?

2 Answers

Enrique Munguía
Enrique Munguía
14,311 Points
Enrique Munguía
Enrique Munguía
14,311 Points

Yeah you are right, you can write a switch statement checking the string you receive and it will work. In this case an enum is used to encapsulate all expected cases, this helps to have a better documented code stating which values are legal to use.

Britt Green
Britt Green
2,611 Points
Britt Green
Britt Green
2,611 Points

Makes sense. Thanks! ;)

Karl Metum
Karl Metum
3,447 Points
Karl Metum
Karl Metum
3,447 Points

Also, we do not need the switch statement at all!

We could simple rewrite the Icon enum like this: 

enum Icon: String {
    case ClearDay = "clear-day"
    case ClearNight = "clear-night"
    case Rain = "rain"
    case Snow = "snow"
    case Sleet = "sleet"
    case Wind = "wind"
    case Fog = "fog"
    case Cloudy = "cloudy"
    case PartlyCloudyDay = "partly-cloudy-day"
    case PartlyCloudyNight = "partly-cloudy-night"

    func toImage() -> UIImage {   
        return UIImage(named: "\(self).png")
    }
}
Tommy Choe
Tommy Choe
38,156 Points
Tommy Choe
Tommy Choe
38,156 Points

Thanks! You answered my question.

Edit: Just a heads-up. So the images for a cloudy day and cloudy night are named "cloudy-day.png" and "cloudy-night.png" NOT as "partly-cloudy-day.png" and "partly-cloudy-night.png".

I decided not to change the image name and handle it with conditionals instead. 

func toImage() -> UIImage?{
        print("\(self.rawValue).png")
        if self == .PartlyCloudyDay {
            return UIImage(named: "cloudy-day.png")
        } else if self == .PartlyCloudyNight {
            return UIImage(named: "cloudy-night.png")
        } else {
            return UIImage(named: "\(self)")
        }
    }

Anyways happy coding!

Grayson Webster
Grayson Webster
11,528 Points

Make sure to change "self" to "self.rawValue" if you use this method.

KB Li
KB Li
Courses Plus Student 625 Points
KB Li
KB Li
Courses Plus Student 625 Points

Hi Karl, this is a very good practice.

However, by doing string interpolation, we have to make sure they(images) are all in the same format PNG, which might not be the case. So I think it actually makes sense to use switch in this case, because it is more flexible though cumbersome :).