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SOLVED: What is .init?

Forums > 100 Days of SwiftUI

example from Day 21:

RadialGradient(stops: [
    .init(color: Color(red: 0.1, green: 0.2, blue: 0.45), location: 0.3),
    .init(color: Color(red: 0.76, green: 0.15, blue: 0.26), location: 0.3),
], center: .top, startRadius: 200, endRadius: 400)
    .ignoresSafeArea()

   

So an initializer is a method that sets up a struct or class or enum so that it can be used.

The initializer for RadialGradient that is being used here looks like this:

init(stops: [Gradient.Stop], center: UnitPoint, startRadius: CGFloat, endRadius: CGFloat)

You can see that the first parameter takes an array of Gradient.Stop items. So you have to provide an array of those, which is usually done like this:

[
    Gradient.Stop(color: ...,location: ...),
    Gradient.Stop(color: ...,location: ...),
    Gradient.Stop(color: ...,location: ...),
]

But since Gradient.Stop(...) is just a shorthand for calling the initializer, you can instead write it like this:

[
    Gradient.Stop.init(color: ...,location: ...),
    Gradient.Stop.init(color: ...,location: ...),
    Gradient.Stop.init(color: ...,location: ...),
]

And since Swift's type inference knows it's looking for Gradient.Stop items here, you can actually leave out the type part and just use .init, like so:

[
    .init(color: ...,location: ...),
    .init(color: ...,location: ...),
    .init(color: ...,location: ...),
]

Et voilà!

5      

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