尝试在 SwiftUI 中添加全屏活动指示器。
我可以使用协议中.overlay(overlay: )的功能View。
有了这个，我可以制作任何视图覆盖，但我UIActivityIndicatorView在SwiftUI.
如何使用 制作默认样式微调器SwiftUI？
注意：这不是在 UIKit 框架中添加活动指示器。
问问题
94959 次
15 回答
343
从Xcode 12 beta ( iOS 14 ) 开始，开发人员可以使用一个名为的新视图ProgressView，它可以显示确定和不确定的进度。
它的样式默认为CircularProgressViewStyle，这正是我们正在寻找的。
var body: some View {
VStack {
ProgressView()
// and if you want to be explicit / future-proof...
// .progressViewStyle(CircularProgressViewStyle())
}
}
Xcode 11.x
相当多的视图尚未在 中表示SwiftUI，但很容易将它们移植到系统中。您需要包装UIActivityIndicator并制作它UIViewRepresentable。
（有关这方面的更多信息，请参阅出色的 WWDC 2019 演讲 -集成 SwiftUI）
struct ActivityIndicator: UIViewRepresentable {
@Binding var isAnimating: Bool
let style: UIActivityIndicatorView.Style
func makeUIView(context: UIViewRepresentableContext<ActivityIndicator>) -> UIActivityIndicatorView {
return UIActivityIndicatorView(style: style)
}
func updateUIView(_ uiView: UIActivityIndicatorView, context: UIViewRepresentableContext<ActivityIndicator>) {
isAnimating ? uiView.startAnimating() : uiView.stopAnimating()
}
}
然后您可以按如下方式使用它 - 这是加载叠加层的示例。
注意：我更喜欢使用ZStack，而不是overlay(:_)，所以我确切地知道我的实现中发生了什么。
struct LoadingView<Content>: View where Content: View {
@Binding var isShowing: Bool
var content: () -> Content
var body: some View {
GeometryReader { geometry in
ZStack(alignment: .center) {
self.content()
.disabled(self.isShowing)
.blur(radius: self.isShowing ? 3 : 0)
VStack {
Text("Loading...")
ActivityIndicator(isAnimating: .constant(true), style: .large)
}
.frame(width: geometry.size.width / 2,
height: geometry.size.height / 5)
.background(Color.secondary.colorInvert())
.foregroundColor(Color.primary)
.cornerRadius(20)
.opacity(self.isShowing ? 1 : 0)
}
}
}
}
要对其进行测试，您可以使用以下示例代码：
struct ContentView: View {
var body: some View {
LoadingView(isShowing: .constant(true)) {
NavigationView {
List(["1", "2", "3", "4", "5"], id: \.self) { row in
Text(row)
}.navigationBarTitle(Text("A List"), displayMode: .large)
}
}
}
}
结果：
于 2019-06-07T15:05:22.097 回答
89
iOS 14
这只是一个简单的视图。
ProgressView()
目前，它默认为，CircularProgressViewStyle但您可以通过添加以下修饰符手动设置它的样式：
.progressViewStyle(CircularProgressViewStyle())
此外，风格可以是任何符合ProgressViewStyle
iOS 13 及更高版本
SwiftUI 中完全可定制的标准
UIActivityIndicator：（完全作为原生View）：
您可以构建和配置它（尽可能多地在原始版本中UIKit）：
ActivityIndicator(isAnimating: loading)
.configure { $0.color = .yellow } // Optional configurations ( bouns)
.background(Color.blue)
只需实现这个基础struct，你就会很高兴：
struct ActivityIndicator: UIViewRepresentable {
typealias UIView = UIActivityIndicatorView
var isAnimating: Bool
fileprivate var configuration = { (indicator: UIView) in }
func makeUIView(context: UIViewRepresentableContext<Self>) -> UIView { UIView() }
func updateUIView(_ uiView: UIView, context: UIViewRepresentableContext<Self>) {
isAnimating ? uiView.startAnimating() : uiView.stopAnimating()
configuration(uiView)
}
}
边界扩展：
有了这个有用的小扩展，你可以modifier像其他 SwiftUI 一样访问配置view：
extension View where Self == ActivityIndicator {
func configure(_ configuration: @escaping (Self.UIView)->Void) -> Self {
Self.init(isAnimating: self.isAnimating, configuration: configuration)
}
}
经典方式：
您还可以在经典初始化程序中配置视图：
ActivityIndicator(isAnimating: loading) {
$0.color = .red
$0.hidesWhenStopped = false
//Any other UIActivityIndicatorView property you like
}
于 2019-11-26T17:30:12.123 回答
73
如果你想要一个swift-ui 风格的解决方案，那么这就是魔法：
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
}
}
只需使用：
ActivityIndicator()
.frame(width: 50, height: 50)
希望能帮助到你！
示例用法：
ActivityIndicator()
.frame(size: CGSize(width: 200, height: 200))
.foregroundColor(.orange)
于 2019-12-04T07:50:25.953 回答
25
自定义指标
虽然 Apple 现在从 SwiftUI 2.0 开始支持原生 Activity Indicator，但您可以简单地实现自己的动画。SwiftUI 1.0 都支持这些。它也在小部件中工作。
弧线
struct Arcs: View {
@Binding var isAnimating: Bool
let count: UInt
let width: CGFloat
let spacing: CGFloat
var body: some View {
GeometryReader { geometry in
ForEach(0..<Int(count)) { index in
item(forIndex: index, in: geometry.size)
.rotationEffect(isAnimating ? .degrees(360) : .degrees(0))
.animation(
Animation.default
.speed(Double.random(in: 0.2...0.5))
.repeatCount(isAnimating ? .max : 1, autoreverses: false)
)
}
}
.aspectRatio(contentMode: .fit)
}
private func item(forIndex index: Int, in geometrySize: CGSize) -> some View {
Group { () -> Path in
var p = Path()
p.addArc(center: CGPoint(x: geometrySize.width/2, y: geometrySize.height/2),
radius: geometrySize.width/2 - width/2 - CGFloat(index) * (width + spacing),
startAngle: .degrees(0),
endAngle: .degrees(Double(Int.random(in: 120...300))),
clockwise: true)
return p.strokedPath(.init(lineWidth: width))
}
.frame(width: geometrySize.width, height: geometrySize.height)
}
}
不同变体的演示
酒吧
struct Bars: View {
@Binding var isAnimating: Bool
let count: UInt
let spacing: CGFloat
let cornerRadius: CGFloat
let scaleRange: ClosedRange<Double>
let opacityRange: ClosedRange<Double>
var body: some View {
GeometryReader { geometry in
ForEach(0..<Int(count)) { index in
item(forIndex: index, in: geometry.size)
}
}
.aspectRatio(contentMode: .fit)
}
private var scale: CGFloat { CGFloat(isAnimating ? scaleRange.lowerBound : scaleRange.upperBound) }
private var opacity: Double { isAnimating ? opacityRange.lowerBound : opacityRange.upperBound }
private func size(count: UInt, geometry: CGSize) -> CGFloat {
(geometry.width/CGFloat(count)) - (spacing-2)
}
private func item(forIndex index: Int, in geometrySize: CGSize) -> some View {
RoundedRectangle(cornerRadius: cornerRadius, style: .continuous)
.frame(width: size(count: count, geometry: geometrySize), height: geometrySize.height)
.scaleEffect(x: 1, y: scale, anchor: .center)
.opacity(opacity)
.animation(
Animation
.default
.repeatCount(isAnimating ? .max : 1, autoreverses: true)
.delay(Double(index) / Double(count) / 2)
)
.offset(x: CGFloat(index) * (size(count: count, geometry: geometrySize) + spacing))
}
}
不同变体的演示
护目镜
struct Blinking: View {
@Binding var isAnimating: Bool
let count: UInt
let size: CGFloat
var body: some View {
GeometryReader { geometry in
ForEach(0..<Int(count)) { index in
item(forIndex: index, in: geometry.size)
.frame(width: geometry.size.width, height: geometry.size.height)
}
}
.aspectRatio(contentMode: .fit)
}
private func item(forIndex index: Int, in geometrySize: CGSize) -> some View {
let angle = 2 * CGFloat.pi / CGFloat(count) * CGFloat(index)
let x = (geometrySize.width/2 - size/2) * cos(angle)
let y = (geometrySize.height/2 - size/2) * sin(angle)
return Circle()
.frame(width: size, height: size)
.scaleEffect(isAnimating ? 0.5 : 1)
.opacity(isAnimating ? 0.25 : 1)
.animation(
Animation
.default
.repeatCount(isAnimating ? .max : 1, autoreverses: true)
.delay(Double(index) / Double(count) / 2)
)
.offset(x: x, y: y)
}
}
不同变体的演示
为了防止代码墙，您可以在托管在 git 上的这个 repo中找到更优雅的指标。
请注意，所有这些动画都有一个Binding必须切换才能运行。
于 2020-10-09T17:22:17.177 回答
6
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()
}
}
}
}
}
于 2020-12-29T08:12:19.677 回答
5
SwiftUI 中的活动指示器
import SwiftUI
struct Indicator: View {
@State var animateTrimPath = false
@State var rotaeInfinity = false
var body: some View {
ZStack {
Color.black
.edgesIgnoringSafeArea(.all)
ZStack {
Path { path in
path.addLines([
.init(x: 2, y: 1),
.init(x: 1, y: 0),
.init(x: 0, y: 1),
.init(x: 1, y: 2),
.init(x: 3, y: 0),
.init(x: 4, y: 1),
.init(x: 3, y: 2),
.init(x: 2, y: 1)
])
}
.trim(from: animateTrimPath ? 1/0.99 : 0, to: animateTrimPath ? 1/0.99 : 1)
.scale(50, anchor: .topLeading)
.stroke(Color.yellow, lineWidth: 20)
.offset(x: 110, y: 350)
.animation(Animation.easeInOut(duration: 1.5).repeatForever(autoreverses: true))
.onAppear() {
self.animateTrimPath.toggle()
}
}
.rotationEffect(.degrees(rotaeInfinity ? 0 : -360))
.scaleEffect(0.3, anchor: .center)
.animation(Animation.easeInOut(duration: 1.5)
.repeatForever(autoreverses: false))
.onAppear(){
self.rotaeInfinity.toggle()
}
}
}
}
struct Indicator_Previews: PreviewProvider {
static var previews: some View {
Indicator()
}
}
于 2019-12-24T16:46:09.653 回答
4
我使用 SwiftUI 实现了经典的 UIKit 指示器。 在此处查看活动指示器
struct ActivityIndicator: View {
@State private var currentIndex: Int = 0
func incrementIndex() {
currentIndex += 1
DispatchQueue.main.asyncAfter(deadline: .now() + .milliseconds(50), execute: {
self.incrementIndex()
})
}
var body: some View {
GeometryReader { (geometry: GeometryProxy) in
ForEach(0..<12) { index in
Group {
Rectangle()
.cornerRadius(geometry.size.width / 5)
.frame(width: geometry.size.width / 8, height: geometry.size.height / 3)
.offset(y: geometry.size.width / 2.25)
.rotationEffect(.degrees(Double(-360 * index / 12)))
.opacity(self.setOpacity(for: index))
}.frame(width: geometry.size.width, height: geometry.size.height)
}
}
.aspectRatio(1, contentMode: .fit)
.onAppear {
self.incrementIndex()
}
}
func setOpacity(for index: Int) -> Double {
let opacityOffset = Double((index + currentIndex - 1) % 11 ) / 12 * 0.9
return 0.1 + opacityOffset
}
}
struct ActivityIndicator_Previews: PreviewProvider {
static var previews: some View {
ActivityIndicator()
.frame(width: 50, height: 50)
.foregroundColor(.blue)
}
}
于 2020-06-12T03:37:31.590 回答
3
我进行了一些更新，以便可以将其放入一个快速包中：
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)
}}
扩大：
public extension View where Self == ActivityIndicator {
func configure(_ configuration: @escaping (Self.UIView) -> Void) -> Self {
Self.init(isAnimating: self.isAnimating, configuration: configuration)
}
}
于 2020-02-07T19:14:50.447 回答
2
使用 SwiftUI 2.0 真的很容易我用这个简单易用的自定义视图ProgressView
这是它的外观：
代码：
import SwiftUI
struct ActivityIndicatorView: View {
@Binding var isPresented:Bool
var body: some View {
if isPresented{
ZStack{
RoundedRectangle(cornerRadius: 15).fill(CustomColor.gray.opacity(0.1))
ProgressView {
Text("Loading...")
.font(.title2)
}
}.frame(width: 120, height: 120, alignment: .center)
.background(RoundedRectangle(cornerRadius: 25).stroke(CustomColor.gray,lineWidth: 2))
}
}
}
于 2021-01-07T10:42:56.940 回答
2
您有ProgressView()的.progressViewStyle修饰符，您可以在其中更改活动指示器的样式。
于 2021-07-12T13:46:58.630 回答
1
我发现有用的一种方便方法SwiftUI是两步法：
创建一个
ViewModifier将您的视图嵌入ZStack并在顶部添加进度指示器的方法。可能是这样的：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) } }创建视图扩展，使条件修饰符应用程序可用于任何视图：
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 } } }使用非常直观。假设
myView()返回您的视图。.if您只需使用步骤 2 中的视图扩展有条件地应用修改器：var body: some View { myView() .if(myViewModel.isLoading){ view in view.modifier(LoadingIndicator()) } }
如果myViewModel.isLoading为假，则不会应用任何修饰符，因此不会显示加载指示器。
当然，你可以使用任何你想要的进度指示器——默认的或你自己定制的。
于 2021-06-22T11:32:41.470 回答
1
尝试这个：
import SwiftUI
struct LoadingPlaceholder: View {
var text = "Loading..."
init(text:String ) {
self.text = text
}
var body: some View {
VStack(content: {
ProgressView(self.text)
})
}
}
有关 SwiftUI ProgressView的更多信息
于 2020-07-15T20:52:19.163 回答
0
// Activity View
struct ActivityIndicator: UIViewRepresentable {
let style: UIActivityIndicatorView.Style
@Binding var animate: Bool
private let spinner: UIActivityIndicatorView = {
$0.hidesWhenStopped = true
return $0
}(UIActivityIndicatorView(style: .medium))
func makeUIView(context: UIViewRepresentableContext<ActivityIndicator>) -> UIActivityIndicatorView {
spinner.style = style
return spinner
}
func updateUIView(_ uiView: UIActivityIndicatorView, context: UIViewRepresentableContext<ActivityIndicator>) {
animate ? uiView.startAnimating() : uiView.stopAnimating()
}
func configure(_ indicator: (UIActivityIndicatorView) -> Void) -> some View {
indicator(spinner)
return self
}
}
// Usage
struct ContentView: View {
@State var animate = false
var body: some View {
ActivityIndicator(style: .large, animate: $animate)
.configure {
$0.color = .red
}
.background(Color.blue)
}
}
于 2020-02-08T09:48:27.730 回答
0
我已经使用 AppKit 和 SwiftUI 修改了 Matteo Pacini 的 macOS 答案。这允许您在 SwiftUI 中使用 NSProgressIndicator，同时保留 macOS 10.15 的功能。
import AppKit
import SwiftUI
struct ActivityIndicator: NSViewRepresentable {
@Binding var isAnimating: Bool
let style: NSProgressIndicator.Style
func makeNSView(context: NSViewRepresentableContext<ActivityIndicator>) -> NSProgressIndicator {
let progressIndicator = NSProgressIndicator()
progressIndicator.style = self.style
return progressIndicator
}
func updateNSView(_ nsView: NSProgressIndicator, context: NSViewRepresentableContext<ActivityIndicator>) {
isAnimating ? nsView.startAnimation(nil) : nsView.stopAnimation(nil)
}
}
用法如下：
ActivityIndicator(isAnimating: .constant(true), style: .spinning)
于 2022-02-06T10:35:53.373 回答
0
我的 2 美分用于 batuhankrbb 的漂亮和简单的代码，显示了 isPresented 在计时器中的使用......或其他东西......（我将在 url 回调中使用它......）
//
// 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()
}
}
于 2021-01-27T10:26:45.840 回答