GradientBuilder

For design detail, read Go through swift result builders

Installation:

CocoaPods

GradientBuilder is now available through CocoaPods. To install it, simply add the following line to your Podfile:

pod 'GradientBuilder'

Swift Package Manager

GradientBuilder is published with Swift Package Manager, you can get more information at , , and

- Add to Xcode(To use this package in your application):

1. File > Swift Packages > Add Package Dependency...
2. Choose Project you want to add GradientBuilder
3. Paste repository https://github.com/chenhaiteng/GradientBuilder.git
4. Rules > Version: Up to Next Major 1.0.0 It's can also apply Rules > Branch : main to access the latest code.

Note: It might need to link GradientBuilder to your target maunally.

1. Open Project Editor by tap on root of project navigator
2. Choose the target you want to use GradientBuilder.
3. Choose Build Phases, and expand Link Binary With Libraries
4. Tap on + button, and choose GradientBuilder to add it.

- Add to SPM package(To use this package in your library/framework):

dependencies: [
    .package(name: "GradientBuilder", url: " https://github.com/chenhaiteng/GradientBuilder.git", from: "1.0.0")
    // To specify branch, use following statement to instead of.
    // .package(name: "GradientBuilder", url: " https://github.com/chenhaiteng/GradientBuilder.git", .branch("branch_name"))
],
targets: [
    .target(
        name: "MyPackage",
        dependencies: ["GradientBuilder"]),
]

---

How to use

1. apply on function

// Create a Gradient, then inject it into specified gradient shape.
@GradientBuilder
func builder() -> Gradient {
    Color.red
    Color.blue
    Color.yellow
}

let g = builder()
let angularGradient = AngularGradient(gradient: g, center: .center)

// Or create gradient shape directly
@GradientBuilder
func angularBuilder() -> AngularGradient {
    Color.red
    Color.blue
    Color.yellow
}

let angular = angularBuilder()

2. apply on a arameter in a function declaration

func createGradient(@GradientBuilder builder: ()->Gradient) -> Gradient {
    return builder()
}

let g = createGradient {
    Color.red
    Color.blue
    Color.yellow
}

3. apply on a variable or subscript

enum GrayGradient {
    @GradientBuilder static subscript(_ degree: Int) -> LinearGradient {
        if degree > 0 {
            for i in 0..<degree {
                Color.white.opacity(Double(i)/Double(degree))
            }
        } else {
            Color.white
        }
    }
}

let gray_g = GrayGradient[3]

4. Support different input types

let g = createGradient {
    (1.0, 1.0, 1.0, 0.5) //RGBA with float, value from 0.0 to 1.0
    (255, 255, 255, 210) //RGBA8888 format, vlaue from 0 to 255
    Color.white // Color 
}

let g_stop = createGradient {
    Gradient.Stop(color: .red, location: 0.2)
    (Color.blue, 0.5)
    (.green, 0.7)
}

Note that it's NOT allow to mix Color with Stop:

let g = createGradient {
    (1.0, 1.0, 1.0, 0.5) //RGBA with float, value from 0.0 to 1.0
    (255, 255, 255, 210) //RGBA8888 format, vlaue from 0 to 255
    (.green, 0.7) // Invalid!!! show ambiguous error!!!!
}