Intercept custom action on TabView - swift

Question

I was recommended to use the standard components so, instead of building my own TabView, I used SwiftUI's TabView. I only need a custom action that doesn't activate a view but triggers an action.
I almost succeeded to do it with the following code:
import SwiftUI
struct ContentView: View {
#State var value: Int = 1
private var adapterValue: Binding<Int> {
Binding<Int>(get: {
if (self.value == 4) {
return 2
} else {
return self.value
}
}, set: {
if $0 == 4 {
self.value = 2
} else {
self.value = $0
}
})
}
var body: some View {
TabView(selection: self.adapterValue, content: {
Text("A").tabItem {
VStack {
Text("A")
}
}
.tag(1)
Text("B").tabItem {
VStack {
Text("B")
}
}
.tag(2)
Text("C").tabItem {
VStack {
Text("C")
}
}
.tag(3)
Text("D").tabItem {
VStack {
Text("D")
}
}
.tag(4)
})
}
}
It works well, except for when tab 2 (B) is activated and I press 4 (D), tab 4 (D) is activated. This should not happen, but I'm unsure what I'm missing.
I would like to understand the reason why this doesn't work as I expected and how I can prevent this behavior.

Answer 1

you could try this:
struct ContentView: View {
#State var value: Int = 1
var body: some View {
TabView(selection: $value) {
Text("A").tabItem {
VStack {
Text("A")
}
}
.tag(1)
Text("B").tabItem {
VStack {
Text("B")
}
}
.tag(2)
Text("C").tabItem {
VStack {
Text("C")
}
}
.tag(3)
Text("D").tabItem {
VStack {
Text("D")
}
}
.tag(4)
}
.onChange(of: value) { val in
if val == 4 {
self.value = 2
}
}
}
}