我试图创建一个可编辑的环境对象并将其放入列表中。例如，仅当我切换选项卡时（所以每当我离开 NavigationView 时），变量才会刷新，然后再回来。
以前同样适用于 ModalView。这可能是一个错误吗？还是我做错了什么？
import SwiftUI
import Combine
struct TestView: View {
@State var showSheet: Bool = false
@EnvironmentObject var feed: TestObject
func addObjects() {
var strings = ["one","two","three","four","five","six"]
for s in strings {
var testItem = TestItem(text: s)
self.feed.items.append(testItem)
}
}
var body: some View {
TabView {
NavigationView {
List(feed.items.indices, id:\.self) { i in
NavigationLink(destination: detailView(feed: self._feed, i: i)) {
HStack {
Text(self.feed.items[i].text)
Text("(\(self.feed.items[i].read.description))")
}
}
}
}
.tabItem({ Text("Test") })
.tag(0)
Text("Blank")
.tabItem({ Text("Test") })
.tag(0)
}.onAppear {
self.addObjects()
}
}
}
struct detailView: View {
@EnvironmentObject var feed: TestObject
var i: Int
var body: some View {
VStack {
Text(feed.items[i].text)
Text(feed.items[i].read.description)
Button(action: { self.feed.items[self.i].isRead.toggle() }) {
Text("Toggle read")
}
}
}
}
final class TestItem: ObservableObject {
init(text: String) {
self.text = text
self.isRead = false
}
static func == (lhs: TestItem, rhs: TestItem) -> Bool {
lhs.text < rhs.text
}
var text: String
var isRead: Bool
let willChange = PassthroughSubject<TestItem, Never>()
var read: Bool {
set {
self.isRead = newValue
}
get {
self.isRead
}
}
}
class TestObject: ObservableObject {
var willChange = PassthroughSubject<TestObject, Never>()
@Published var items: [TestItem] = [] {
didSet {
willChange.send(self)
}
}
}