SwiftUI .onDelete 从 ForEach 获取 var

Posted 2023-02-24

【中文标题】SwiftUI .onDelete 从 ForEach 获取 var

【英文标题】：SwiftUI .onDelete get var from ForEach

【发布时间】：2020-08-12 08:49:19

【问题描述】：

我有这个代码：

struct CreateInfo: Identifiable 
    var id: String
    var name: String
    var time: String
    var day: String
    var isDeleted: Bool


struct ZettelView: View 
    
    @State var zettelInfos = [CreateInfo]()
    
    @State private var showingAlert = false

    @State private var savedValueForDeleteFunction: CreateInfo
    
    func createNewInfo() 
        
        var arr = [[String]]()
        arr = getZettelData()
                
        
        for x in arr 
            zettelInfos.append(CreateInfo(id: "\(x[0])", name: "\(x[1])", time: "\(x[2])", day: "\(x[3])", isDeleted: false))
        
        
        self.executeThisAsyncThing = false
        
   
    
    
    @State var executeThisAsyncThing: Bool = true
    
    
    
    var body: some View 
    
        
        DispatchQueue.main.async 
            if self.executeThisAsyncThing 
                self.createNewInfo()
            
        
            
        
        return VStack 
            
            //New - testing
            NavigationView 
                List 
                    ForEach(zettelInfos)  x in
                                                
                        
                        NavigationLink(destination: zettelDetailView(uuid: x.id, info: x)) 
                            Text("\(x.id)")
                            
                        

                        
                    .onDelete(perform: delete)
                    
                .navigationBarTitle("Einkaufszettel")
                .navigationBarItems(trailing: Button(action: 
                    self.addRow()
                ) 
                    Image(systemName: "plus.app.fill")
                )
                
            

         .alert(isPresented: $showingAlert) 
                Alert(title: Text(" meImportantssage"), message: Text("Wear sunscreen"), dismissButton: .default(Text("Got it!")))
            
            
            
            
        

        
    
    
    func delete(at offsets: IndexSet) 
                
        zettelInfos.remove(atOffsets: offsets)
        self.showingAlert = true
                
    
    
    
        private func addRow() 
            
            let dateAndTime = Date()
            let dfDay = DateFormatter()
            let dfTime = DateFormatter()
            
            dfDay.dateFormat = "dd.MM.yyyy"
            dfTime.dateFormat = "HH:mm:ss"

            let day = dfDay.string(from: dateAndTime)
            let time = dfTime.string(from: dateAndTime)
            
            
            let x = CreateInfo(id: UUID().uuidString, name: "Neuer Zettel", time: time, day: day, isDeleted: false)
            
            saveZettelData(x: x)
            zettelInfos.append(x)
            

        
    

所以我的问题是，如何将 ForEach 中的 x 变量解析为删除函数？

我为什么要这个？ -> foreach 中的 x 变量有一个 UUID，我需要来自 x 的 UUID

有没有人知道一种方法，我如何从x 获取 UUID？

这是我的第一个 swift 应用程序，我正在努力学习它，但在某些情况下，它与我所知道的其他语言不同。通常我会将一个值解析为一个删除函数，然后遍历它以查找和删除特定的行/数据，但我猜想它是另一种方式。

【参考方案1】：

这是一种方法

func delete(at offsets: IndexSet) 
            
    let index = offsets[offsets.startIndex]
    let x = zettelInfos[index]

    // ... do anything needed with x.id now

    zettelInfos.remove(atOffsets: offsets)
    self.showingAlert = true