Conditional creation of Shapes - SwiftUI

Question

I am trying to write a function that creates a shape according to a specified condition but getting a compilation error.

func createShape() -> some Shape {
    switch self.card.shape {
    case .oval:
        return Capsule()
    case .rectangle:
        return Rectangle()
    case .circe:
        return Circle()
    default:
        return Circle()
    }
}

The error I am getting:

Function declares an opaque return type, but the return statements in its body do not have matching underlying types

Does this answer your question https://stackoverflow.com/a/62605936/12299030? — Asperi, May 16 '21 at 13:19
I need the function `createShape` to return specifically a Shape — Luda, May 16 '21 at 14:40

score 3 · Accepted Answer · answered May 16 '21 at 19:54

With the help of this post, what helped me was:

Creating an AnyShape:

#if canImport(SwiftUI)

import SwiftUI

@available(iOS 13.0, macOS 10.15, tvOS 13.0, watchOS 6.0, *)
public struct AnyShape: Shape {
    public var make: (CGRect, inout Path) -> ()

    public init(_ make: @escaping (CGRect, inout Path) -> ()) {
        self.make = make
    }

    public init<S: Shape>(_ shape: S) {
        self.make = { rect, path in
            path = shape.path(in: rect)
        }
    }

    public func path(in rect: CGRect) -> Path {
        return Path { [make] in make(rect, &$0) }
    }
}

#endif

Then:

func createShape() -> AnyShape {
    switch self.card.shape {
    case .oval:
        return AnyShape(Capsule())
    case .rectangle:
        return AnyShape(Rectangle())
    case .circe:
        return AnyShape(Circle())
    }
}

In iOS16 here was introduce AnyShape struct. I have named your struct UniversalShape in case do not get compile problems. — Ramis, Jul 22 '22 at 08:35

score -1 · Answer 2 · answered May 16 '21 at 13:35

-1

From the comment and link of Asperi:

Change to:

@ViewBuilder
func createShape() -> some View {
    switch self.card.shape {
    case .oval:
        Capsule()
    case .rectangle:
        Rectangle()
    case .circle:
        Circle()
    default:
        Circle()
    }
}

answered May 16 '21 at 13:35

sheldor

115
12

1

I need the function `createShape` to return specifically a Shape – Luda May 16 '21 at 14:33

Conditional creation of Shapes - SwiftUI

2 Answers2