首页 > 解决方案 > 如何在 SwiftUI 中使用枚举控制视图状态

问题描述

如果这是一个愚蠢的问题,我深表歉意,我是 Swift 和编程的新手。我试图弄清楚如何使用枚举在 SwiftUI 中控制我的视图状态。我试图将我的其他视图结构ContentView保留currentViewContentView. 例如,如果我点击 中的按钮StartView,如何影响currentView不同结构中的变量 ?

struct ContentView: View {
    
    enum ViewType {
        case start
        case settings
        case game
        case finish
    }
    
    @State var currentView = ViewType.start
    
    var body: some View {
        
        Group {
            
            if currentView == .start {
                StartView()
    
            } else if currentView == .settings {
                SettingsView()
                
            } else if currentView == .game {
                GameView()
                
            } else if currentView == .finish {
                GameOverView()
            }
        }
    }
}

struct StartView: View {
    
    var body: some View {
        Text("start")
        Button(action: {
            // How can I update my view state from within this struct?
        }, label: {
            Text("Button")
        })
    }
}

任何帮助或资源链接将不胜感激。

谢谢你。

标签: swiftstructswiftuienumsviewstate

解决方案


正如工作狗评论@Binding的那样,只需在每个子视图中添加s :

struct StartView: View {
    @Binding var currentView: ViewType
}
struct SettingsView: View {
    @Binding var currentView: ViewType
}
struct GameView: View {
    @Binding var currentView: ViewType
}
struct GameOverView: View {
    @Binding var currentView: ViewType
}

然后,只需将 传递@State给他们每个人。在每个子视图中所做的所有更改都@Binding var currentView将同步到ContentView's currentView

if currentView == .start {
    StartView(currentView: $currentView)
} else if currentView == .settings {
    SettingsView(currentView: $currentView)
} else if currentView == .game {
    GameView(currentView: $currentView)
} else if currentView == .finish {
    GameOverView(currentView: $currentView)
}

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