Mastering SwiftUI’s onChange

Starting from iOS 14, SwiftUI provides the onChange modifier for views. By using onChange, we can observe specific values in the view and trigger actions when they change. This article will introduce the characteristics, usage, precautions, and alternative solutions of onChange.

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How to use onChange

The definition of onChange is as follows:

func onChange<V>(of value: V, perform action: @escaping (V) -> Void) -> some View where V : Equatable

onChange calls the operation within the closure when a specific value changes.

struct OnChangeDemo:View{
    @State var t = 0
    var body: some View{…