Using onAppear on ForEach - ios

Question

I created View which contains List and under List is Section:
struct SwiftUIView: View {
var body: some View {
List {
Section {
EmptyView()
} header: {
Text("Some header text")
}
NewView()
}
}
}
NewView and SomeViewModel code:
class SomeViewModel: ObservableObject {
#Published var data: [String] = []
func onAppear(){
data = ["One", "Two", "Three"]
}
}
struct NewView: View {
#State private var viewModel = SomeViewModel()
var body: some View {
ForEach(viewModel.data, id: \.self){
Text($0)
}
.onAppear(perform: viewModel.onAppear)
}
}
Problem here is that onAppear modifier is not called on ForEach. When I added Text and use onAppear modifier on it, then it is working, but I don't need one more View. I tried to use EmptyView also, but again, onAppear is not called. Is there any way to call modifiers on ForEach?

Answer 1

Try this approach to call onAppear()
struct ContentView: View {
var body: some View {
NewView()
}
}
class SomeViewModel: ObservableObject {
#Published var data: [String] = []
func onAppear() {
data = ["One", "Two", "Three"]
print("----> in SomeViewModel onAppear")
}
}
struct NewView: View {
#StateObject var viewModel = SomeViewModel() // <-- here
var body: some View {
ForEach(viewModel.data, id: \.self){
Text($0)
}
.onAppear{
viewModel.onAppear() // <-- here
}
}
}

Answer 2

I think you should use init instead of onAppear to init the model
class SomeViewModel: ObservableObject {
#Published var data: [String] = []
init() {
data = ["One", "Two", "Three"]
}
}
struct NewView: View {
#State private var viewModel = SomeViewModel()
var body: some View {
ForEach(viewModel.data, id: \.self){
Text($0)
}
}
}