Update ProgressView value from another ViewController without using #Binding? - ios

Question

Currently I declare my ProgressView in my main view controller which gets it's value from a #State variable. On a button press i change the value of the variable which then updates the value of my progress bar.
I want to make changes to this ProgressView, but using a button on a separate view controller. I've tried to use Binding, but due to the way I am using WatchTabView, this forces me to declare a #Binding variable within my App struct, which isn't possible.
Not sure if I'm overthinking this, but how can i update my progress bar from another view?
Main View
struct ViewController: View {
#State var progressBarValue = 5.0
var body: some View {
ScrollView{
ProgressView("Effort", value: progressBarValue, total: 20)
VStack {
Button{
progressBarValue += 5.0
}label:{
Text("Click")
}
Other View
struct OtherViewController: View{
...
Button{
//I want to increase progressBarValue by clicking here
}label:{
Text("Click")
}
...
}

Answer 1

First please read this post:
What's the difference between a View and a ViewController?
Then read this: https://developer.apple.com/documentation/combine/observableobject
Also, read this: https://www.hackingwithswift.com/quick-start/swiftui/whats-the-difference-between-observedobject-state-and-environmentobject
Finally, come back to this example:
class MyViewController: ObservableObject {
#Published private(set) progress: Float = 0
func updateProgress(by value: Float) {
progress += value
}
}
Parent View:
struct ParentView: View {
#ObservedObject var myController = MyViewController()
var body: some View {
MainChildView()
.environmentObject(myController) //this is one of the ways of passing down an ObservableObject to all underlying views.
//your progress view code can go here
}
}
MainChildView
struct MainChildView: View {
//no need to pass anything into this view because of the EnvironmentObject.
var body: some View {
ChildView()
}
}
ChildView
struct ChildView: View {
#EnvironmentObject var myController: MyViewController //EnvironmentObject will search for MyViewController declared somewhere in one of the parent views
var body: some View {
//your progress view code can go here
Button("Tap", action: {
myController.updateProgress(by: 5)
})
}
}