Sample View to demonstrate how often SwiftUI redraws its views.

SwiftUIRendering.swift

import SwiftUI

struct SampleView: View {

    var texts = ["SwiftUI", "A new declarative UI framework", "Let us try to understand how SwiftUI renders its views"]
    
    @State var selected = 0
    @State var textFieldValue = ""
    @State var isSwitchOn = false
    
    var body: some View {
        VStack(spacing: 16) {
            TextField("Enter your name", text: $textFieldValue)
                .padding(EdgeInsets(top: 8, leading: 16, bottom: 8, trailing: 16))
                .background(Color(UIColor.secondarySystemFill))
                .cornerRadius(4)
            
            Toggle(isOn: $isSwitchOn, label: {
                Text("A simple Switch")
            })
            
            Picker(selection: $selected, label: Text(""), content: {
                Text("Word").tag(0)
                Text("Phrase").tag(1)
                Text("Sentence").tag(2)
            }).pickerStyle(SegmentedPickerStyle())
            
            HStack {
                Text(texts[selected])
                Spacer()
                Button(action: {
                    print("just checking")
                }, label: {
                    Image(systemName: "plus.circle.fill")
                        .foregroundColor(.blue)
                })
            }
            
            
        }.padding()

    }
}