静态@state 字符串字段

Question

我有文本字段，我需要使用静态函数更改文本字段中的文本。

import SwiftUI

struct MainScreen: View
{
   @State static var mytext = "TEXT"
   var body: some View
   {
       Text(MainScreen.mytext)
   }

   public static func showtext(newtext: String)
   {
       MainScreen.mytext = newtext
   }
}

我该怎么做？或者，如果我将使用 @State var mytext = "TEXT"?

，我怎样才能在静态函数中获得 MainScreen.self

P.S.: 对不起我的英文)))

Answer 1

我不明白你为什么坚持使用静态函数来改变你的文本...

也许我错了，但试试这个：

struct MainScreen: View {
@State var myText: String = "Default Text"
var body: some View {
    Text("\(myText)")
}

func changeText(newText: String) {
    self.myText = "New Text Now"
}
}

它对我有用，希望对你也有帮助。

Answer 2

与需要这样做的原因无关，请在下面找到实现请求行为的可能方法。测试并适用于 Xcode 11.2 / iOS 13.2

import Combine

struct MainScreen: View
{
    // shared publisher
    static let publisher = PassthroughSubject<String, Never>()

    @State private var mytext = "TEXT" // << !! can be only per-view, make always private
    var body: some View
    {
        VStack {
            Text(mytext)
                .onReceive(MainScreen.publisher) { value in // listen for shared publisher
                    self.mytext = value // update with new value
            }

            // this button is just for demo
            Button("Show") { MainScreen.showtext(newtext: "Updated Text!") }
        }
    }

    public static func showtext(newtext: String)
    {
        MainScreen.publisher.send(newtext) // post via shared publisher
    }
}

静态@state 字符串字段

Static @state string field

field

class

swift

swiftui