CODEWITHSUNDEEP
iosswiftswiftuipicker
Grayson
Grayson

Reputation: 23

Update SwiftUI picker minimum and maximum when navigating back to a view

I am developing a SwiftUI application that uses pickers. I have 6 pickers that I want to be able to set the minimum and maximum values for. I have a separate view with steppers to set the minimum and maximum of each picker. All of the variables are stored in the environment. Right now, the pickers do not update when navigating from the settings view back to the main view. They do not change until after you move the pickers. Is there a way to have to pickers minimum and maximum values change when the view navigates back rather than having to move the pickers first? This is an example of one of my pickers:

Picker(selection: self.$ticket.pick1, label: Text("")) {
         ForEach(self.ticket.min1 ... self.ticket.max1, id: \.self) {
               Text("\($0)").frame(width: geometry.size.width / 6)
         }
}

Here is an example of one of the minimum and maximum steppers:

Text("Pick One").fontWeight(.bold)
Stepper(value: $ticket.min1, in: 1...100, label: {Text("Minimum: \(ticket.min1)")})
Stepper(value: $ticket.max1, in: 1...100, label: {Text("Maximum: \(ticket.max1)")})

Upvotes: 1

Views: 1016

Answers (1)

E.Coms
E.Coms

Reputation: 11539

When you need to change a picker range realtime, you may consider .id(). The following example can solve this specific question. It may involve other situations in a real complex situation, like data binding. But that's another story.

struct Ticket : Hashable{
     var min1 : Int
     var max1 : Int
     var pick1 : Int
}

struct CoolPickers: View {
      @State var ticket: Ticket = Ticket(min1: 1, max1: 10, pick1: 2)

      var body: some View {
            GeometryReader { geometry in
                 NavigationView{
                      VStack{
                            NavigationLink("Next", destination: SettingPickersView(ticket: self.$ticket))
                        Picker(selection: self.$ticket.pick1, label: Text("")) {
                            ForEach(self.ticket.min1 ... self.ticket.max1, id: \.self) {
                                    Text("\($0)")
                                    .frame(width: geometry.size.width / 6)
                                }
                        }.id(self.ticket)
                      }
                 }
            }
      }
}

struct SettingPickersView: View {
       @Binding var ticket: Ticket

       var body: some View {
             Group{
                  Text("Pick One").fontWeight(.bold)
                  Stepper(value: $ticket.min1, in: 1...100, label: {Text("Minimum: \(ticket.min1)")})
                  Stepper(value: $ticket.max1, in: 1...100, label: {Text("Maximum: \(ticket.max1)")})
             }
       }
}

Upvotes: 1

Related Questions