当我在 SwiftUI 中使用 EnvironmentObject 时，选择器正在弹回

Posted 2023-02-24

【中文标题】当我在 SwiftUI 中使用 EnvironmentObject 时，选择器正在弹回

【英文标题】：Picker is springing back when I use an EnvironmentObject in SwiftUI

【发布时间】：2020-01-17 08:14:46

【问题描述】：

我创建了一个安静简单的 Picker，并希望将 EnvironmentObject 用作​​数据源，但是当我使用它时，Picker 总是弹回默认值。

class HobbiesOfUser: ObservableObject 
@Published var hobbies = ["Swimming", "Football", "Hockey", "Rugby", "Other"]

struct ContentView: View 

    @EnvironmentObject var hobbiesOfUser: HobbiesOfUser
//   @State var hobbiesOfUser = ["Swimming", "Football", "Hockey", "Rugby", "Other"]

    var body: some View 
                            Picker(selection: $hobbiesOfUser.hobbies, label: Text("")) 
                            ForEach(0 ..< hobbiesOfUser.hobbies.count) 
                                Text(self.hobbiesOfUser.hobbies[$0]).tag($0)
                            .labelsHidden()
        
    

我尝试过选择另一种形式的 Picker，但它有同样的问题

【参考方案1】：

选择应该是数组的一项，而不是完整的数组，如下

@EnvironmentObject var hobbiesOfUser: HobbiesOfUser

@State private var selected = "Swimming"
var body: some View 
        Picker(selection: $selected, label: Text("")) 
        ForEach(0 ..< hobbiesOfUser.hobbies.count) 
            Text(self.hobbiesOfUser.hobbies[$0]).tag($0)
        .labelsHidden()