eecs441staff

// UM EECS 441

import SwiftUI

struct Froggy: ViewModifier {
    func body(content: Content) -> some View {
        content
            .font(.custom("Times New Roman", size: 32))
            .foregroundColor(.green)
            .bold()

eecs441staff

// UM EECS 441

import SwiftUI

func Haiku() -> String {
    "Furu ike ya kawazu tobikomu mizu no oto"
    /*
     "Furu ike ya"
    "kawazu tobikomu"
    "mizu no oto"

eecs441staff

// UM EECS 441

import SwiftUI

struct ContentView: View {
    @State var count = 0
    
    var body: some View {
        let _ = print("hello")
        

eecs441staff

// UM EECS 441

import SwiftUI

struct Music {
    var title = "Ninth Symphony"
    var composer = "Beethoven"
    var playlist = "Classical"
}

eecs441staff

// UM EECS 441

import SwiftUI

@propertyWrapper
struct SimpleState<T>: DynamicProperty {
    private var _state: State<T>    // references SwiftUI memory outside of struct
    var wrappedValue: T {
        get { _state.wrappedValue }  // accesses reference to SwiftUI memory
        nonmutating set { _state.wrappedValue = newValue }    // no change to reference

eecs441staff

// UM EECS 441

import SwiftUI
import Observation

@Observable // for subscription
final class HeapStore<T> {
    var value: T
    init(initValue: T) {
        value = initValue

eecs441staff

// UM EECS 441

import SwiftUI

@main
struct StateValueApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
                .environment(A(1))

eecs441staff

// UM EECS 441

import SwiftUI
import Observation

@Observable
final class RefCounter {
    var count = 0
    var name = "counter"
}

eecs441staff

// UM EECS 441

import SwiftUI
import Observation

@Observable
final class RefCounter {
    var count = 0
    var name = "counter"
}

eecs441staff

// UM EECS 441

import SwiftUI
import Observation

@Observable
final class RefCounter {
    var count = 0
    @ObservationIgnored var name = "counter"
    func inc() { count += 1 }