xcode - SwiftUI: how to create custom UIDatePicker
问题描述
I succeeded to create UIDatePicker inside SwifUI, but when I change the date wheel in picker the date value not update, here is my code:
struct DatePicker: UIViewRepresentable {
@Binding var date: Date
func makeUIView(context: Context) -> UIDatePicker {
let view = UIDatePicker()
view.datePickerMode = .date
return view
}
func updateUIView(_ uiView: UIDatePicker, context: Context) {
uiView.date = date
}
}
Then I call it from the view like this:
struct SwiftUIView: View {
@State var date = Date()
var body: some View {
DatePicker(date: self.$date)
}
}
解决方案
带有可选参数的扩展DatePicker方法(基于@Asperi 答案)。
struct DatePickerUIKit: UIViewRepresentable {
@Binding private var selection: Date
private let range: ClosedRange<Date>?
private var minimumDate: Date? {
range?.lowerBound
}
private var maximumDate: Date? {
range?.upperBound
}
private var minuteInterval: Int
private let datePicker = UIDatePicker()
init(selection: Binding<Date>, in range: ClosedRange<Date>?, minuteInterval: Int = 1) {
self._selection = selection
self.range = range
self.minuteInterval = minuteInterval
}
func makeUIView(context: Context) -> UIDatePicker {
datePicker.datePickerMode = .dateAndTime
datePicker.minuteInterval = minuteInterval
datePicker.minimumDate = minimumDate
datePicker.maximumDate = maximumDate
datePicker.addTarget(context.coordinator, action: #selector(Coordinator.changed(_:)), for: .valueChanged)
return datePicker
}
func updateUIView(_ uiView: UIDatePicker, context: Context) {
datePicker.date = selection
}
func makeCoordinator() -> DatePickerUIKit.Coordinator {
Coordinator(selection: $selection, in: range, minuteInterval: minuteInterval)
}
class Coordinator: NSObject {
private let selection: Binding<Date>
private let range: ClosedRange<Date>?
private let minuteInterval: Int
init(selection: Binding<Date>, in range: ClosedRange<Date>? = nil, minuteInterval: Int = 1) {
self.selection = selection
self.range = range
self.minuteInterval = minuteInterval
}
@objc func changed(_ sender: UIDatePicker) {
self.selection.wrappedValue = sender.date
}
}
}
例如设置分钟间隔,SwiftUI尚不支持:
@State var dateFrom = Date()
let minMaxRange = Date().dateAtStartOf(.day)...Date().dateAtEndOf(.day) + 3.days
DatePickerUIKit(selection: $dateFrom,
range: minMaxRange, minuteInterval: 30)
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