I'm struggling with the following issue: I'm trying to build a very simple app that lets you add items in a dedicated view that can be collapsed. I managed to write a simple function that lets me add multiple of these custom collapsable views. It's my first app so I wanted to follow the MVVM protocol. I think I got confused along the way because now every item I add gets automatically added to all the custom collapsable views I made. Is there any way to fix this? I thought using the UUID would solve this issue.. I'm guessing that I have to customise the "saveButtonPressed" function, but I don't know how to tell it to only add the item to the view where I pressed the "plus" button..
struct ItemModel: Identifiable, Equatable {
let id: String
let title: String
init(id: String = UUID().uuidString, title: String) {
self.id = id
self.title = title
}
func updateCompletion() -> ItemModel {
return ItemModel(id: id, title: title)
}
}
--
import Foundation
struct CollapsableItem: Equatable, Identifiable, Hashable {
let id: String
var title: String
init(id: String = UUID().uuidString, title: String) {
self.id = id
self.title = title
}
func updateCompletion() -> CollapsableItem {
return CollapsableItem(id: id, title: title)
}
}
class ListViewModel: ObservableObject {
@Published var items: [ItemModel] = []
init() {
getItems()
}
func getItems() {
let newItems = [
ItemModel(title: "List Item1"),
ItemModel(title: "List Item2"),
ItemModel(title: "List Item3"),
]
items.append(contentsOf: newItems)
}
func addItem(title: String) {
let newItem = ItemModel(title: title)
items.append(newItem)
}
func updateItem(item: ItemModel) {
if let index = items.firstIndex(where: { $0.id == item.id}) {
items[index] = item.updateCompletion()
}
}
}
--
class CollapsedViewModel: ObservableObject {
@Published var collapsableItems: [CollapsableItem] = []
@Published var id = UUID().uuidString
init() {
getCollapsableItems()
}
func getCollapsableItems() {
let newCollapsableItems = [
CollapsableItem(title: "Wake up")
]
collapsableItems.append(contentsOf: newCollapsableItems)
}
func addCollapsableItem(title: String) {
let newCollapsableItem = CollapsableItem(title: title)
collapsableItems.append(newCollapsableItem)
}
func updateCollapsableItem(collapsableItem: CollapsableItem) {
if let index = collapsableItems.firstIndex(where: { $0.id ==
collapsableItem.id}) {
collapsableItems[index] =
collapsableItem.updateCompletion()
}
}
}
struct ListRowView: View {
@EnvironmentObject var listViewModel: ListViewModel
let item: ItemModel
var body: some View {
HStack() {
Text(item.title)
.font(.body)
.fontWeight(.bold)
.foregroundColor(.white)
.multilineTextAlignment(.center)
.lineLimit(1)
.frame(width: 232, height: 16)
}
.padding( )
.frame(width: 396, height: 56)
.background(.gray)
.cornerRadius(12.0)
}
}
struct CollapsedView2<Content: View>: View {
@State var collapsableItem: CollapsableItem
@EnvironmentObject var collapsedViewModel: CollapsedViewModel
@State private var collapsed: Bool = true
@EnvironmentObject var listViewModel: ListViewModel
@State var label: () -> Text
@State var content: () -> Content
@State private var show = true
var body: some View {
ZStack{
VStack {
HStack{
Button(
action: { self.collapsed.toggle() },
label: {
HStack() {
Text("Hello")
.font(.title2.bold())
Spacer()
Image(systemName: self.collapsed ? "chevron.down" :
"chevron.up")
}
.padding(.bottom, 1)
.background(Color.white.opacity(0.01))
}
)
.buttonStyle(PlainButtonStyle())
Button(action: saveButtonPressed, label: {
Image(systemName: "plus")
.font(.title2)
.foregroundColor(.white)
})
}
VStack {
self.content()
}
ForEach(listViewModel.items) { item in ListRowView (item: item)
}
.lineLimit(1)
.fixedSize(horizontal: true, vertical: true)
.frame(minWidth: 396, maxWidth: 396, minHeight: 0, maxHeight: collapsed ?
0 : .none)
.animation(.easeInOut(duration: 1.0), value: show)
.clipped()
.transition(.slide)
}
}
}
func saveButtonPressed() {
listViewModel.addItem(title: "Hello")
}
}
struct ListView: View {
@EnvironmentObject var listViewModel: ListViewModel
@EnvironmentObject var collapsedViewModel: CollapsedViewModel
var body: some View {
ZStack{
ScrollView{
VStack{
HStack{
Text("MyFirstApp")
.font(.largeTitle.bold())
Button(action: newCollapsablePressed, label: {
Image(systemName: "plus")
.font(.title2)
.foregroundColor(.white)
})
}
.padding()
.padding(.leading)
ForEach(collapsedViewModel.collapsableItems) { collapsableItem in
CollapsedView2 (collapsableItem: collapsableItem,
label: { Text("") .font(.title2.bold()) },
content: {
HStack {
Text("")
Spacer() }
.frame(maxWidth: .infinity)
})
}
.padding()
}
}
.frame(maxWidth: .infinity, maxHeight: .infinity)
.statusBar(hidden: false)
.navigationBarHidden(true)
}
}
func newCollapsablePressed() {
collapsedViewModel.addCollapsableItem(title: "hello2")
}
}
Would love to understand how I could fix this!
There is the anwser for your comment about add item in each CollapsedView2. Because ListViewModel is not ObservableObject (ListViewModel is difference from each CollapsableItem). You should use "@State var items: [ItemModel]".
struct CollapsedView2<Content: View>: View {
@State var collapsableItem: CollapsableItem
// @State var listViewModel = ListViewModel()
@State var collapsed: Bool = true
@State var label: () -> Text
@State var content: () -> Content
@State private var show = true
@State var items: [ItemModel] = []
@State var count = 1
var body: some View {
VStack {
HStack{
Text("Hello")
.font(.title2.bold())
Spacer()
Button( action: { self.collapsed.toggle() },
label: {
Image(systemName: self.collapsed ? "chevron.down" : "chevron.up")
}
)
.buttonStyle(PlainButtonStyle())
Button(action: saveButtonPressed, label: {
Image(systemName: "plus")
.font(.title2)
// .foregroundColor(.white)
})
}
VStack {
self.content()
}
ForEach(items) { item in
ListRowView (item: item)
}
.lineLimit(1)
.fixedSize(horizontal: true, vertical: true)
.frame(minHeight: 0, maxHeight: collapsed ? 0 : .none)
.animation(.easeInOut(duration: 1.0), value: show)
.clipped()
.transition(.slide)
}
}
func saveButtonPressed() {
addItem(title: "Hello \(count)")
count += 1
}
func addItem(title: String) {
let newItem = ItemModel(title: title)
items.append(newItem)
}
func updateItem(item: ItemModel) {
if let index = items.firstIndex(where: { $0.id == item.id}) {
items[index] = item.updateCompletion()
}
}
}