[SwiftUI] 왜 $를 붙인 Binding 값을 사용하나요?

// // FrameworkDetailView.swift // AppleFramework-SwiftUI // // Created by tonyyun on 10/27/23. // import SwiftUI struct FrameworkDetailView: View { @StateObject var viewModel: FrameworkDetailViewModel var body: some View { VStack(spacing: 20) { Spacer() Image(viewModel.framework.imageName) .resizable() .frame(width: 80, height: 80) Text(viewModel.framework.name) .font(.system(size: 24, weight: .bold)) Text(viewModel.framework.description) Spacer() Button(action: { viewModel.isSafariPresented = ...