如何在 Swift UI 中每小时更改显示（例如星巴克咖啡应用程序）

Question

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我希望 Swift UI 显示在像星巴克应用程序一样在指定时间导航查看（“早上好”在 5:00，“下午好”在 12:00，“晚安”在 17:00）。请告诉我。

Answer 1

您可以将当前时间与为每个标题设置的时间进行比较，以达到您想要的效果

import SwiftUI

struct SwiftUIView: View {
    // MARK: - PROPERTIES
    
    @State private var navigationTitle = ""
    
    // MARK: - BODY
    
    var body: some View {
        NavigationView {
            VStack{    
            }//: VSTACK
            .navigationTitle(navigationTitle) //TITLE
        }//: NAVIGATION
        .onAppear {
            let morningTime = "05:00:00"
            let noonTime = "12:00:00"
            let nightTime = "17:00:00"
            //DateFormatter
            let dateFormatter = DateFormatter()
            dateFormatter.dateFormat = "hh:mm:ss"
            let currentTime = dateFormatter.string(from: Date())
            //Conditions to compare time
            if currentTime >= morningTime && currentTime < noonTime{
                navigationTitle = "Good Morning"
            }else if currentTime >= noonTime && currentTime < nightTime{
                navigationTitle = "Good Afternoon"
            }else{
                navigationTitle = "Good Night"
            }
        }
    }
}

// MARK: - PREVIEW

struct SwiftUIView_Previews: PreviewProvider {
    static var previews: some View {
        SwiftUIView()
    }
}