如何将从列表中选择的多个项目传递到下一个视图？答案

【问题标题】：How do I pass multiple items selected from list to next view?如何将从列表中选择的多个项目传递到下一个视图？
【发布时间】：2021-09-16 17:11:07
【问题描述】：

在我看来，我问了用户 2 个问题。在每个问题下方，我都有一个列表，允许用户选择多个项目。

如何将从列表中选择的多个项目传递到下一个视图？
如何打印选择以在 Xcode 中调试控制台？

这是我在 Xcode 中的 Swift 代码：

import SwiftUI

struct WelcomeView: View {
    
    @State var applications: [Application] = [Application(name: "Beer"),
                                              Application(name: "Hard Seltzer")]
    
    @State var legislations: [Legislation] = [Legislation(name: "Natural"),
                                              Legislation(name: "Natural and Artificial")]
    
    var body: some View {
        NavigationView {
            VStack {
                Text("Which applications are you interested in?")
                    .padding()
                List{
                    ForEach(0..<applications.count){ index in
                        HStack {
                            Button(action: {
                                applications[index].isSelected = applications[index].isSelected ? false : true
                            }) {
                                HStack{
                                    if applications[index].isSelected {
                                        Image(systemName: "checkmark.circle.fill")
                                            .foregroundColor(.green)
                                            .animation(.easeIn)
                                    } else {
                                        Image(systemName: "circle")
                                            .foregroundColor(.primary)
                                            .animation(.easeOut)
                                    }
                                    Text(applications[index].name)
                                }
                            }.buttonStyle(BorderlessButtonStyle())
                        }
                    }
                }
                Text("Which legislations are you interested in?")
                    .padding()
                List{
                    ForEach(0..<legislations.count){ index in
                        HStack {
                            Button(action: {
                                legislations[index].isSelected = legislations[index].isSelected ? false : true
                            }) {
                                HStack{
                                    if legislations[index].isSelected {
                                        Image(systemName: "checkmark.circle.fill")
                                            .foregroundColor(.green)
                                            .animation(.easeIn)
                                    } else {
                                        Image(systemName: "circle")
                                            .foregroundColor(.primary)
                                            .animation(.easeOut)
                                    }
                                    Text(legislations[index].name)
                                }
                            }.buttonStyle(BorderlessButtonStyle())
                        }
                    }
                }
                NavigationLink(destination: FlavorSearchView()) {
                    Text("Next")
                        .padding()
                }
            }
        }
    }
}

struct Application: Identifiable {
        var id = UUID()
        var name: String
        var isSelected: Bool = false
}

struct Legislation: Identifiable {
        var id = UUID()
        var name: String
        var isSelected: Bool = false
}

struct WelcomeView_Previews: PreviewProvider {
    static var previews: some View {
        WelcomeView()
    }
}

屏幕预览：

link to screen view image

【问题讨论】：

请提供足够的代码，以便其他人更好地理解或重现问题。

标签： ios swift xcode swiftui

【解决方案1】：

您可以将数组作为参数传递给下一个视图，如下所示：

NavigationLink(destination: FlavorSearchView(applications: applications, legislations: legislations))

并在视图的构造函数中打印选择：

struct FlavorSearchView: View {
    
    init (applications: [Application], legislations: [Legislation]){
        self.applications = applications
        self.legislations = legislations
        
        print(applications)
        print(legislations)
    }
    
    let applications: [Application]
    let legislations: [Legislation]
    
    var body: some View{
        VStack{ }
    }
}

这种方法肯定会触发 SwiftUI 中自动弹出的已知错误。在这里讨论： https://developer.apple.com/forums/thread/677333

【讨论】：