我的2美分的漂亮和更简单的代码的batuhankrbb，显示使用定时器中的ispresents…或者其他东西…(我将使用它在url回调..)

//
//  ContentView.swift
//
//  Created by ing.conti on 27/01/21.


import SwiftUI

struct ActivityIndicatorView: View {
    @Binding var isPresented:Bool
    var body: some View {
        if isPresented{
            ZStack{
                RoundedRectangle(cornerRadius: 15).fill(Color.gray.opacity(0.1))
                ProgressView {
                    Text("Loading...")
                        .font(.title2)
                }
            }.frame(width: 120, height: 120, alignment: .center)
            .background(RoundedRectangle(cornerRadius: 25).stroke(Color.gray,lineWidth: 2))
        }
    }
}



struct ContentView: View {
    @State var isPresented = false
    @State var counter = 0
    var body: some View {
        
        VStack{
            Text("Hello, world! \(counter)")
                .padding()
            
            ActivityIndicatorView(isPresented: $isPresented)
        }.onAppear(perform: {
            _ = startRefreshing()
        })
    }
    
    
    
    func startRefreshing()->Timer{
        
        let timer = Timer.scheduledTimer(withTimeInterval: 1, repeats: true) { timer in
            
            counter+=1
            print(counter)
            if counter>2{
                isPresented = true
            }
            
            if counter>4{
                isPresented = false
                timer.invalidate()
            }
        }
        return timer
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

除了Mojatba Hosseini的回答，

我做了一些更新，这样就可以把它放在一个快速包中:

活动指标:

import Foundation
import SwiftUI
import UIKit

public struct ActivityIndicator: UIViewRepresentable {

  public typealias UIView = UIActivityIndicatorView
  public var isAnimating: Bool = true
  public var configuration = { (indicator: UIView) in }

 public init(isAnimating: Bool, configuration: ((UIView) -> Void)? = nil) {
    self.isAnimating = isAnimating
    if let configuration = configuration {
        self.configuration = configuration
    }
 }

 public func makeUIView(context: UIViewRepresentableContext<Self>) -> UIView {
    UIView()
 }

 public func updateUIView(_ uiView: UIView, context: 
    UIViewRepresentableContext<Self>) {
     isAnimating ? uiView.startAnimating() : uiView.stopAnimating()
     configuration(uiView)
}}

扩展:

public extension View where Self == ActivityIndicator {
func configure(_ configuration: @escaping (Self.UIView) -> Void) -> Self {
    Self.init(isAnimating: self.isAnimating, configuration: configuration)
 }
}

如果你想要一个swift-ui风格的解决方案，那么神奇的是:

import Foundation
import SwiftUI

struct ActivityIndicator: View {
    
    @State private var isAnimating: Bool = false
    
    var body: some View {
        GeometryReader { (geometry: GeometryProxy) in
            ForEach(0..<5) { index in
                Group {
                    Circle()
                        .frame(width: geometry.size.width / 5, height: geometry.size.height / 5)
                        .scaleEffect(calcScale(index: index))
                        .offset(y: calcYOffset(geometry))
                }.frame(width: geometry.size.width, height: geometry.size.height)
                    .rotationEffect(!self.isAnimating ? .degrees(0) : .degrees(360))
                    .animation(Animation
                                .timingCurve(0.5, 0.15 + Double(index) / 5, 0.25, 1, duration: 1.5)
                                .repeatForever(autoreverses: false))
            }
        }
        .aspectRatio(1, contentMode: .fit)
        .onAppear {
            self.isAnimating = true
        }
    }
    
    func calcScale(index: Int) -> CGFloat {
        return (!isAnimating ? 1 - CGFloat(Float(index)) / 5 : 0.2 + CGFloat(index) / 5)
    }
    
    func calcYOffset(_ geometry: GeometryProxy) -> CGFloat {
        return geometry.size.width / 10 - geometry.size.height / 2
    }
    
}

简单地使用:

ActivityIndicator()
.frame(width: 50, height: 50)

希望能有所帮助!

使用示例:

ActivityIndicator()
    .frame(width: 200, height: 200)
    .foregroundColor(.orange)

在SwiftUI中，我发现一个方便的方法是两步方法:

Create a ViewModifier that will embed your view into ZStack and add progress indicator on top. Could be something like this: struct LoadingIndicator: ViewModifier { let width = UIScreen.main.bounds.width * 0.3 let height = UIScreen.main.bounds.width * 0.3 func body(content: Content) -> some View { return ZStack { content .disabled(true) .blur(radius: 2) //gray background VStack{} .frame(width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height) .background(Color.gray.opacity(0.2)) .cornerRadius(20) .edgesIgnoringSafeArea(.all) //progress indicator ProgressView() .frame(width: width, height: height) .background(Color.white) .cornerRadius(20) .opacity(1) .shadow(color: Color.gray.opacity(0.5), radius: 4.0, x: 1.0, y: 2.0) } } Create view extension that will make conditional modifier application available to any view: extension View { /// Applies the given transform if the given condition evaluates to `true`. /// - Parameters: /// - condition: The condition to evaluate. /// - transform: The transform to apply to the source `View`. /// - Returns: Either the original `View` or the modified `View` if the condition is `true`. @ViewBuilder func `if`<Content: View>(_ condition: Bool, transform: (Self) -> Content) -> some View { if condition { transform(self) } else { self } } } Usage is very intuitive. Suppose that myView() returns whatever your view is. You just conditionally apply the modifier using .if view extension from step 2: var body: some View { myView() .if(myViewModel.isLoading){ view in view.modifier(LoadingIndicator()) } }

如果是myViewModel。isLoading为false，没有修饰符将被应用，因此加载指示器将不显示。

当然，您可以使用任何类型的进度指示器—默认的或您自己的自定义的。

我的2美分的漂亮和更简单的代码的batuhankrbb，显示使用定时器中的ispresents…或者其他东西…(我将使用它在url回调..)

//
//  ContentView.swift
//
//  Created by ing.conti on 27/01/21.


import SwiftUI

struct ActivityIndicatorView: View {
    @Binding var isPresented:Bool
    var body: some View {
        if isPresented{
            ZStack{
                RoundedRectangle(cornerRadius: 15).fill(Color.gray.opacity(0.1))
                ProgressView {
                    Text("Loading...")
                        .font(.title2)
                }
            }.frame(width: 120, height: 120, alignment: .center)
            .background(RoundedRectangle(cornerRadius: 25).stroke(Color.gray,lineWidth: 2))
        }
    }
}



struct ContentView: View {
    @State var isPresented = false
    @State var counter = 0
    var body: some View {
        
        VStack{
            Text("Hello, world! \(counter)")
                .padding()
            
            ActivityIndicatorView(isPresented: $isPresented)
        }.onAppear(perform: {
            _ = startRefreshing()
        })
    }
    
    
    
    func startRefreshing()->Timer{
        
        let timer = Timer.scheduledTimer(withTimeInterval: 1, repeats: true) { timer in
            
            counter+=1
            print(counter)
            if counter>2{
                isPresented = true
            }
            
            if counter>4{
                isPresented = false
                timer.invalidate()
            }
        }
        return timer
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

struct ContentView: View {
    
    @State private var isCircleRotating = true
    @State private var animateStart = false
    @State private var animateEnd = true
    
    var body: some View {
        
        ZStack {
            Circle()
                .stroke(lineWidth: 10)
                .fill(Color.init(red: 0.96, green: 0.96, blue: 0.96))
                .frame(width: 150, height: 150)
            
            Circle()
                .trim(from: animateStart ? 1/3 : 1/9, to: animateEnd ? 2/5 : 1)
                .stroke(lineWidth: 10)
                .rotationEffect(.degrees(isCircleRotating ? 360 : 0))
                .frame(width: 150, height: 150)
                .foregroundColor(Color.blue)
                .onAppear() {
                    withAnimation(Animation
                                    .linear(duration: 1)
                                    .repeatForever(autoreverses: false)) {
                        self.isCircleRotating.toggle()
                    }
                    withAnimation(Animation
                                    .linear(duration: 1)
                                    .delay(0.5)
                                    .repeatForever(autoreverses: true)) {
                        self.animateStart.toggle()
                    }
                    withAnimation(Animation
                                    .linear(duration: 1)
                                    .delay(1)
                                    .repeatForever(autoreverses: true)) {
                        self.animateEnd.toggle()
                    }
                }
        }
    }
}