SwiftUI: Apply a linear gradient to a shape using a Custom Class - swiftui

Question

How do I apply a linear gradient with a custom class that I made on a shape? For some reason it is not working for me. The foregroundColor is not working for me.
RoundedRectangle(cornerRadius: 30)
.frame(width: geometry.size.width * 1.01, height:geometry.size.height * 0.23)
.rotationEffect(.degrees(12), anchor: .center)
.foregroundColor(LinearGradient (gradient: Gradient(colors:[Color(ColorsSaved.gitLabDark),Color(ColorsSaved.gitLabLight)]),startPoint: .leading,endPoint: .trailing))
I created my CustomClass in a Swift file. Please see code below for that.
import Foundation
import UIKit
struct ColorsSaved {
static let gitLabDark = UIColor( red: 0.12, green: 0.08, blue: 0.22, alpha: 1.0)
static let gitLabLight = UIColor( red: 0.26, green: 0.2, blue: 0.44, alpha: 1.0)
static let neonGreen = UIColor(red: 0.497, green: 0.738, blue: 0.35, alpha: 1)
static let darkGreenTorquise = UIColor(red: 0.242, green: 0.683, blue: 0.577, alpha: 1)
static let brightOrange = UIColor(red: 0.917, green: 0.469, blue: 0.218, alpha: 1)

Answer 1

If I correctly understood your intention, I would go with the following approach.
Result demo:
Code:
GeometryReader { geometry in
LinearGradient(gradient:
Gradient(colors:
[Color(ColorsSaved.gitLabDark), Color(ColorsSaved.gitLabLight)]),
startPoint: .leading, endPoint: .trailing)
.frame(width: geometry.size.width * 1.01, height:geometry.size.height * 0.23)
.mask(RoundedRectangle(cornerRadius: 30))
.rotationEffect(.degrees(12), anchor: .center)
}

Answer 2

Gradients in SwiftUI are supposed to be added with the help of ZStack. As you haven't added much code in your question I made my assumptions. Try this in your custom view:
struct WelcomeView: View {
var body: some View {
ZStack {
LinearGradient(gradient: Gradient(colors: [.pink, .purple]), startPoint: .leading, endPoint: .trailing)
// here goes your other view component
Text("Welcome, John")
}
}
}