為什么我不能在我的SwiftUI專案中使用多個“.alert”對話框？

我想洗掉串列項，當我洗掉串列項時，它會顯示確認對話框，如.alert對話框。我有下面的代碼，如果我想洗掉串列項.alert對話框是有效的，但是如果我嘗試洗掉所有串列項，.alert對話框不起作用，并且我無法洗掉所有專案，我不知道我錯過了什么？我想很可能是因為我有兩個.alert對話而且它們是沖突的，知道嗎？

 struct CustomView: View {

    @State private var selectedUsers: CustomModel?
    @State var users: [CustomModel]
    @State private var selectDelete = false
    @State private var selectAllDelete = false

    var body: some View {
        ScrollView(.vertical, showsIndicators: false, content: {  
            VStack(content: {
                ForEach(users){ user in
                    CustomRowView(user: user)
                        .contextMenu {
                            Button(action: {

                            selectDelete = true

                            }) {
                                Text("remove") 
                            }
                     Button(action: {
                           selectAllDelete = true
                            }) {
                                Text("remove all") 
                            }
                        }
                       
                        .alert(isPresented: $selectDelete) {
                            Alert(title: Text("title"),
                                message: Text("message"),
                                primaryButton: .destructive(Text("Delete")) {
                                      self.delete(item: data)
                                },
                                secondaryButton: .cancel()
                            )
                        }
                       .alert(isPresented: $selectAllDelete) {
                            Alert(title: Text("title"),
                                message: Text("message"),
                                primaryButton: .destructive(Text("Delete")) {
                                           self.datas.removeAll()
                                },
                                secondaryButton: .cancel()
                            )
                         }
                        .onDelete { (indexSet) in
                            self.users.remove(atOffsets: indexSet)
                        }
                 }
            })
        })
    }

    private func delete(item user: CustomModel) {
        if let index = users.firstIndex(where: { $0.id == user.id }) {
            users.remove(at: index)
        }
    }
}

模型：

struct CustomModel: Identifiable{
var id = UUID().uuidString
var name: String
}

var users = [

CustomModel(name: "david"),
CustomModel(name: "marry"),
CustomModel(name: "henry"),
CustomModel(name: "nadi"), ]

uj5u.com熱心網友回復：

您可以創建警報型別并使用 switch 陳述句對其進行處理。

enum AlertType {
    case selectDelete
    case selectAllDelete
}

private var alertType: AlertType?
@State private var isAlertPresented = false

...

Button(action: {
    alertType = .selectDelete
    isAlertPresented = true
}) {
    Text("remove all") 
}

...

.alert(isPresented: $isAlertPresented) {
    presentAlert()
}

...

func presentAlert() -> Alert {
    switch alertType {
    case .selectDelete:
        return Alert(title: Text("title"), 
            message: Text("message"),
            primaryButton: .destructive(Text("Delete")) {
                self.delete(item: data)
            },
            secondaryButton: .cancel())
    case .selectAllDelete:
        return Alert(title: Text("title"), 
            message: Text("message"), 
            primaryButton: .destructive(Text("Delete")) {
                self.datas.removeAll()
            },
            secondaryButton: .cancel())
    default:
        return Alert(title: Text(""))
    }
}

uj5u.com熱心網友回復：

如果您將修改器應用于每個Button，它將起作用。此外，您可能會發現確認對話框更適合此任務。

將您的按鈕移動到自定義視圖中也會有所幫助，因為主體有 10 個視圖限制。

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