Swift UI DatePicker赢得';t更新@ObservedObject值
我使用一个类来存储@Published变量,但当我试图将在自定义日期选择器上选择的值传递给类中的@ObservedObject时,我收到以下错误:Swift UI DatePicker赢得';t更新@ObservedObject值,swift,datepicker,swiftui,combine,observedobject,Swift,Datepicker,Swiftui,Combine,Observedobject,我使用一个类来存储@Published变量,但当我试图将在自定义日期选择器上选择的值传递给类中的@ObservedObject时,我收到以下错误: TimePicker(time: self.$time.**timeSelected**) 无法转换“Binding”(aka)类型的值 “Binding”)到预期的参数类型“TimeModel” 如何使用选择器值更新@ObservedObject 完整代码: struct ContentView: View { @Observe
TimePicker(time: self.$time.**timeSelected**)
无法转换“Binding”(aka)类型的值
“Binding”)到预期的参数类型“TimeModel”
如何使用选择器值更新@ObservedObject
完整代码:
struct ContentView: View {
@ObservedObject var time = TimeModel()
var body: some View {
ZStack{
VStack{
TimePicker(time: self.$time.timeSelected)
Text("You chose \(time.timeSelected/60) minutes")
}
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
class TimeModel: ObservableObject{
@Published var timeSelected: TimeInterval = 1.0
}
struct TimePicker: UIViewRepresentable {
@ObservedObject var time = TimeModel()
func makeUIView(context: Context) -> UIDatePicker {
let datePicker = UIDatePicker()
datePicker.datePickerMode = .countDownTimer
datePicker.addTarget(context.coordinator,
action: #selector(Coordinator.updateTime),
for: .valueChanged)
return datePicker
}
func updateUIView(_ datePicker: UIDatePicker, context: Context) {
datePicker.minuteInterval = 5
datePicker.countDownDuration = time.timeSelected
}
func makeCoordinator() -> Coordinator {
Coordinator(self)
}
class Coordinator: NSObject {
let parent: TimePicker
init(_ parent: TimePicker) {
self.parent = parent
}
@objc func updateTime(datePicker: UIDatePicker) {
parent.time.timeSelected = datePicker.countDownDuration
}
}
}
您需要引用相同的TimeModel
实例
解决方案是将时间模型
传递给时间选择器
:
struct TimePicker: UIViewRepresentable {
@ObservedObject var time: TimeModel // <- declare only
...
}
struct ContentView: View {
@ObservedObject var time = TimeModel()
var body: some View {
ZStack {
VStack {
TimePicker(time: time) // <- pass `TimeModel` here
Text("You chose \(time.timeSelected / 60) minutes")
}
}
}
}
实际上,将默认时间设置为1秒。谢谢您的快速修复@pawello2222为什么要在TimePicker结构下声明而不是初始化TimeModel?@ThomSides在这两种情况下,您都希望引用相同的
TimeModel
实例,因此只需要创建一次,然后传递。
@Published var timeSelected: TimeInterval = 1.0