我现在有文本,我想每秒使用警报更新该文本。
这是我完成的代码。
struct CountDownView : View {
var body: some View {
VStack{
Text("Update text with timer").lineLimit(nil).padding(20)
}.navigationBarTitle(Text("WWDC"), displayMode:.automatic)
}
}
使用 combine:
struct CurrentDateView : View {
@State var now = Date()
let timer = Timer.publish(every: 1, on: .current, in: .common).autoconnect()
var body: some View {
Text("(now)")
.onReceive(timer) {
self.now = Date()
}
}
}
我已经设法使用警报更新文本。
我已将日期声明为 State
因此无论何时使用警报文本更改日期,也会更新。
struct CurrentDateView : View {
@State var newDate = Date()
let timer = Timer.publish(every: 1, on: .current, in: .common).autoconnect()
var body: some View {
Text("(newDate)")
.onReceive(timer) {
self.newDate = Date()
}
}
}
原始样本位于:
https://www.hackingwithswift.com/quick-start/swiftui/how-to-use-a-timer-with-swiftui
我确实使用这种方法定期更新我的一个电话......
另请参阅:
https://developer.apple.com/documentation/combine/replacing-foundation-timers-with-timer-publishers
struct ContentView: View {
@State var msg = ""
var body: some View {
let timer = Timer.publish(every: 1, on: .current, in: .common).autoconnect()
Text(msg)
.onReceive(timer) { input in
msg = MyManager.shared.ifo ?? "not yet received"
}
}
}
我确实必须以其他方式致电网络,但在这里我只是定期打电话给我的一些经理。
停止计时器(如来自hackingSwift的链接。您可以使用:
self.timer.upstream.connect().cancel()