Closures in the Environment

EnvironmentClosure.swift

// replying to https://mastodon.world/@luckkerr/110684106839939474

import SwiftUI

struct MiscellaneousAction {
    let action: () -> Void
    
    init(_ action: @escaping () -> Void) {
        self.action = action
    }
    
    func callAsFunction() {
        action()
    }
}

struct MiscActionKey: EnvironmentKey {
    static var defaultValue: MiscellaneousAction = .init({})
}

extension EnvironmentValues {
    var miscAction: MiscellaneousAction {
        get { self[MiscActionKey.self] }
        set { self[MiscActionKey.self] = newValue }
    }
}

struct ContentView: View {
    var body: some View {
        ChildView()
            .environment(\.miscAction, MiscellaneousAction {
                print(Int.random(in: 0...999).formatted())
            })
            .tint(Color.random())
    }
}

struct ChildView: View {
    @Environment(\.miscAction) private var misc: MiscellaneousAction
    
    var body: some View {
        Button("Alphabet") { misc() }
            .buttonStyle(.borderedProminent)
            .bold(Bool.random())
            .italic(Bool.random())
    }
}

extension Color {
    static func random() -> Self {
        [.green, .yellow, .orange, .red, .purple, .blue].randomElement()!
    }
}