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I'm working on an iPad app that's essentially a large form (with text fields, pickers, etc).Initially I made the whole UI using @State variables just to get the UI behaviour working, now I want to transition to using @Published vars in view models, etc. I do desire bidirectional binding.When I moved all the @State Strings to @ObservedObject and @Published the performance of typing in the text fields became very slow and choppy.It seems worse the more I add. Performance was buttery smooth with @State, but as soon as I made them the view model @ObservedObject things went downhill.Using Xcode 11.2.1 and iPad simulator (though it's still choppy in an iPhone simulator). 2018 MBP.Either I'm misunderstanding the way @ObservedObject and @Published works and it's chasing it's tail or something, or there could be a problem in Combine/SwiftUI somewhere?I've included some demo code, even half this many elements still results in a noticable choppy experience.import SwiftUI import Combine struct ContentView: View { //Slow @ObservedObject var viewModel: ViewModel = ViewModel() //Smooth //@State var viewModel: ViewModel = ViewModel() var body: some View { Form { Section { Group { HStack { Text("Derp") TextField("Derp", text: $viewModel.field1) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field2) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field3) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field4) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field5) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field6) } } Group { HStack { Text("Derp") TextField("Derp", text: $viewModel.field7) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field8) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field9) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field10) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field11) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field12) } } Group { HStack { Text("Derp") TextField("Derp", text: $viewModel.field13) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field14) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field15) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field16) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field17) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field18) } } Group { HStack { Text("Derp") TextField("Derp", text: $viewModel.field19) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field20) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field21) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field22) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field23) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field24) } } Group { HStack { Text("Derp") TextField("Derp", text: $viewModel.field19) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field20) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field21) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field22) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field23) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field24) } } Group { HStack { Text("Derp") TextField("Derp", text: $viewModel.field19) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field20) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field21) } HStack { Text("Derp") TextField("Derp", text: $viewModel.field22) } } } } } } class ViewModel: ObservableObject { @Published var field1: String = "" @Published var field2: String = "" @Published var field3: String = "" @Published var field4: String = "" @Published var field5: String = "" @Published var field6: String = "" @Published var field7: String = "" @Published var field8: String = "" @Published var field9: String = "" @Published var field10: String = "" @Published var field11: String = "" @Published var field12: String = "" @Published var field13: String = "" @Published var field14: String = "" @Published var field15: String = "" @Published var field16: String = "" @Published var field17: String = "" @Published var field18: String = "" @Published var field19: String = "" @Published var field20: String = "" @Published var field21: String = "" @Published var field22: String = "" @Published var field23: String = "" @Published var field24: String = "" }