An SwiftUI button that executes an asynchronous action. The task is automatically cancelled when the lifetime of the button ends.

AsyncButton.swift

import SwiftUI

/// A Button that executes an asynchronous task. The task will be cancelled if the button's lifetime ends before the task does.
struct AsyncButton<Label: View>: View {
    private let role: ButtonRole?
    private let action: @Sendable @MainActor () async -> Void
    private let label: Label
    
    @Environment(\.isLoading) var isLoading
    @State private var actionInProgress: Bool = false
    @State private var task: Task<Void, Never>?
    
    private var loadingInProgress: Bool {
        actionInProgress || isLoading
    }
    
    /// A Button that executes an asynchronous task. The task will be cancelled if the button's lifetime ends before the task does.
    /// - Parameters:
    ///   - role: An optional semantic role that describes the button. A value of nil means that the button doesn’t have an assigned role.
    ///   - action: The asynchronous action to perform when the user interacts with the button.
    ///   - label: A view that describes the purpose of the button’s action.
    init(
        role: ButtonRole? = nil,
        action: @escaping @Sendable @MainActor () async -> Void,
        label: () -> Label
    ) {
        self.role = role
        self.action = action
        self.label = label()
    }
    
    var body: some View {
        Button(role: role) {
            task = Task { [action] in
                await action()
            }
        } label: {
            ZStack {
                label
                    .opacity(loadingInProgress ? 0 : 1)
                
                Image(systemName: "ellipsis")
                    .symbolEffect(.variableColor.iterative.dimInactiveLayers.nonReversing, options: .repeat(.continuous))
                    .font(.largeTitle)
                    .opacity(loadingInProgress ? 1 : 0)
            }
        }
        .allowsHitTesting(!loadingInProgress)
        .task(id: task) {
            guard let action = task else {
                return
            }
            
            actionInProgress = true
            await action.value
            task = nil
            actionInProgress = false
        }
    }
}