SwiftUI 不同目的地的導航欄項目

Question

我有一個帶有添加按鈕 (NavigationBarItem) 的導航視圖，我想在每個選項卡中設置不同的導航欄項目目的地。

enum Tab: String {
    case income = "Income"
    case expenses = "Expenses"
    case budgets = "Budget"
    case investment = "Investment"
    case assets = "Asset"  
}

我已經嘗試將視圖作為原始值提供給結構，但這是不可能的。 我怎樣才能做到這一點？

var body: some View {
    NavigationView {
        TabView(selection: $selection) {
            Text("Place Holder Income")
                .tabItem {
                    Label("Income", systemImage: "star")
                }
                .tag(Tab.income)
                .navigationBarHidden(false)
            
            ExpensesView()
                .tabItem {
                    Label("Expenses", systemImage: "star")
                }
                .tag(Tab.expenses)
                .navigationBarHidden(false)
            
            Text("Place Holder Budgets")
                .tabItem {
                    Label("Budgets", systemImage: "star")
                }
                .tag(Tab.budgets)
                .navigationBarHidden(false)
            
            Text("Place Holder Investment")
                .tabItem {
                    Label("Investment", systemImage: "star")
                }
                .tag(Tab.investment)
                .navigationBarHidden(false)
            
            Text("Place Holder Assets")
                .tabItem {
                    Label("Assets", systemImage: "star")
                }
                .tag(Tab.assets)
                .navigationBarHidden(false)
    }
        .navigationTitle(selection.rawValue)
        .navigationBarItems(
            trailing:
                NavigationLink("Add", destination: AddExpensesView())
        )
    
    }
}

Answer 1

您可以添加一個 function（在您看來）路由到正確的目的地（取決於“選擇”屬性的值）。

@ViewBuilder func addView() -> some View {
        switch selection {
        case .income: Text("Income destination")
        case .expenses: Text("Expenses destination")
        default: Rectangle()
        }
    }

您的NavigationLink調用此視圖生成器：

NavigationLink("Add", destination: addView())