SwiftUI：有条件的 onDelete

Posted 2023-02-24

【中文标题】SwiftUI：有条件的 onDelete

【英文标题】：SwiftUI: Conditional onDelete

【发布时间】：2020-10-05 17:26:40

【问题描述】：

我正在尝试创建一个仅允许用户在进入编辑模式后删除的列表。我试图尝试在 onDelete 修饰符中使用三元运算，但无法弄清楚。有什么建议吗？

这是我的代码：

struct ContentView: View 
    @State private var stuff = ["First", "Second", "Third"]
    @State private var check = false
    
    var body: some View 
        Form 
            Button(action:  check.toggle() , label:  Text(check ? "Editing" : "Edit") )
            
            ForEach(0..<stuff.count)  items in
                Section Text(stuff[items]) 
            
             .onDelete(perform: self.deleteItem)
               
        
    
    
    private func deleteItem(at indexSet: IndexSet) 
        self.stuff.remove(atOffsets: indexSet)
    

【参考方案1】：

我假设您正在寻找以下内容

var body: some View 
    Form 
        Button(action:  check.toggle() , label:  Text(check ? "Editing" : "Edit") )
        
        ForEach(0..<stuff.count)  items in
            Section Text(stuff[items]) 
        
         .onDelete(perform: self.deleteItem)
         .deleteDisabled(!check)             // << this one !!
    

【参考方案2】：

struct ContentView: View 
    @State private
    var stuff = ["First", "Second", "Third"]
    var body: some View 
        NavigationView 
            Form 
                ForEach(0..<stuff.count)  item in
                    Section 
                        Text(stuff[item])
                    
                
                .onDelete(
                    perform: delete)
            
            .navigationBarItems(
                trailing:
                    EditButton()
            )
            .navigationTitle("Test")
        
    


extension ContentView 
    private func delete(at indexSet: IndexSet) 
        stuff.remove(atOffsets: indexSet)