DatePickerNullable.swift

import SwiftUI

struct DatePickerNullable: View {
    let title: String
    @Binding var selected: Date?
    let defaultDate: Date
    
    var body: some View {
        HStack {
            if let date = Binding($selected) {
                DatePicker(
                    title,
                    selection: date,
                    displayedComponents: [.date, .hourAndMinute]
                )
                .datePickerStyle(.field)
                Button(action: {
                    selected = nil
                }) {
                    Image(systemName: "xmark.circle").font(.title2)
                }
                .padding(.trailing)
            } else {
                Button(action: {
                    selected = defaultDate
                }) {
                    HStack {
                        Text("\(title) is empty")
                        Image(systemName: "plus.circle")
                    }
                }
                .background(Color.clear)
                Spacer()
            }
        }
    }
}

I made a lot of corrections on this gist because I noticed that the previous version led to memory leaks