import SwiftUI struct RedrawOnViewModifier: ViewModifier { @State private var changeFlag: Bool init(changeFlag: Bool) { self.changeFlag = changeFlag } func body(content: Content) -> some View { content.opacity(changeFlag ? 1 : 1) } } extension View { func redrawOn(change flag: Bool) -> some View { modifier(RedrawOnViewModifier(changeFlag: flag)) } }