Can the entire View be prevented from being redrawn every second when only a single @State property is updated every second by a Timer in SwiftUI?

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Yes, it is possible to prevent the entire View from being redrawn every second when only a single @State property is updated every second by a Timer in SwiftUI.

This can be achieved by using the @ObservedObject property wrapper instead of the @State property wrapper.

@ObservedObject is used to wrap an instance of a class that conforms to the ObservableObject protocol, which allows us to update specific properties without redrawing the entire View.

Here's an example:

class MyViewModel: ObservableObject {
    @Published var currentTime = Date()

    init() {
        Timer.scheduledTimer(withTimeInterval: 1, repeats: true) { _ in
            self.currentTime = Date()
        }
    }
}

struct ContentView: View {
    @ObservedObject var viewModel = MyViewModel()

    var body: some View {
        Text(viewModel.currentTime.description)
    }
}

In this example, the ViewModel class conforms to the ObservableObject protocol and contains a @Published property called currentTime.

The ContentView observes the viewModel using the @ObservedObject property wrapper, and only renders the Text view when the currentTime property changes.

By using @ObservedObject instead of @State, we ensure that only the Text view is redrawn when the currentTime property updates, instead of redrawing the entire View.