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Problems using a View Model array

Forums > SwiftUI

getting index out of range.....

New to Swift so anyhelp would be greatly appreciated!

import SwiftUI

@Observable class ViewModule { init() {} var name = "" }

var viewModel: [ViewModule] = []

struct ContentView: View { var body: some View { VStack { Button ("Test") { viewModel[0].name = "test" //get index out of range } } } }

Preview {




That because you do not have any items in the array and trying to change an item.

You need to .append(value: Hashable>) to the array in the Button action


Hello. Why do you want to use an array of @Observable object?

If you want to use ViewModel, i think you should do this way:

Define a model:

struct TestData  {
  var name: String

Define a viewModel:

class ViewModel {
  var testData = [TestData]()

in your view:

struct ContentView: View {
      @State var viewModel = ViewModel()

       var body: some View {
             Button {
                   viewModel.testData.append(TestData(name: "TestName"))
             } label: {
                 Text("Add item")


How might this work if you then tried to access the same array from a second ViewModel?


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