how can I refresh another cell when change observedObject - ios

Question

When I select a cell, I want to deselect it from the other cell. After making the selection, I cannot remove the selection from the previous cell. What is the reason of this ? Sorry. I know little English.
Enum
enum Page {
case newest
case populer
case iPhone
case iPad
case mac
case watch
}
ViewModel
class MainViewModel: ObservableObject {
#Published var selectedTab = Page.newest
}
Category Model
struct Category: Identifiable {
var id = UUID()
var title: String
var icon: String
var color: Color
var page: Page
}
Basic Category
let basicCategory = [
Category(title: "En Yeniler", icon: "flame", color: .red, page: .newest),
Category(title: "Popüler", icon: "star", color: .yellow, page: .populer),
]
Cell
struct TabView: View {
var title: String = ""
var icon: String = ""
var color: Color
var page: Page
#ObservedObject var macMainVM = MainViewModel()
var body: some View {
Button(action: {
withAnimation(.spring(response: 0.5, dampingFraction: 0.6, blendDuration: 0)) {
self.macMainVM.selectedTab = self.page
}
}) {
VStack {
Image(systemName: icon)
.imageScale(.large)
.foregroundColor(color)
Text(title)
.font(.custom("Oswald-Light", size: 14))
.fixedSize()
}
.padding(5)
//I emphasize the choice here
.background(self.macMainVM.selectedTab == self.page ? RoundedRectangle(cornerRadius: 10).stroke(color) : nil)
}
.buttonStyle(PlainButtonStyle())
}
}
ForEach
VStack {
ForEach(basicCategory, id: \.id) { item in
TabView(title: item.title, icon: item.icon, color: item.color, page: item.page)
}
}

Answer 1

Updated my answer with the working answer.
The problem was that you were using #ObservedObject instead of a #StateObject
Always use #StateObject for the parent view and #ObservedObject for the children view.
import SwiftUI
struct stackT: View {
#StateObject var macMainVM = MainViewModel()
var body: some View {
VStack {
ForEach(basicCategory, id: \.id) { item in
TabView(macMainVM: macMainVM, title: item.title, icon: item.icon, color: item.color, page: item.page)
}
}
}
}
struct stackT_Previews: PreviewProvider {
static var previews: some View {
stackT()
}
}
struct TabView: View {
#ObservedObject var macMainVM: MainViewModel
var title: String = ""
var icon: String = ""
var color: Color
let page: Page
var body: some View {
Button(action: {
withAnimation(.spring(response: 0.5, dampingFraction: 0.6, blendDuration: 0)) {
DispatchQueue.main.async {
self.macMainVM.globalTab = page
print(macMainVM.globalTab)
}
}
}) {
VStack {
Image(systemName: icon)
.imageScale(.large)
.foregroundColor(color)
Text(title)
.font(.custom("Oswald-Light", size: 14))
.fixedSize()
}
.padding(5)
//I emphasize the choice here
.background(self.macMainVM.globalTab == self.page ? RoundedRectangle(cornerRadius: 10).stroke(color) : RoundedRectangle(cornerRadius: 10).stroke(.clear))
}
.buttonStyle(PlainButtonStyle())
}
}
class MainViewModel: ObservableObject {
#Published var globalTab = Page.newest
}
enum Page {
case newest
case populer
case iPhone
case iPad
case mac
case watch
case none
}
struct Category: Identifiable {
var id = UUID()
var title: String
var icon: String
var color: Color
var page: Page
}
let basicCategory = [
Category(title: "En Yeniler", icon: "flame", color: .red, page: .newest),
Category(title: "Popüler", icon: "star", color: .yellow, page: .populer),
Category(title: "Another", icon: "book", color: .blue, page: .mac)
]

Answer 2

Below are the approaches for single selection and multiple selection.
For single selection you can pass Page as Bindings to subView.
For multiple selection you can maintain a boolean state array, that can tell if current cell was already selected or not.
Single Selection
import SwiftUI
enum Page:String {
case newest
case populer
case iPhone
case iPad
case mac
case watch
}
struct Category: Identifiable {
var id = UUID()
var title: String
var icon: String
var color: Color
var page: Page
}
class MainViewModel: ObservableObject {
#Published var selectedTab = Page.newest
}
struct TabView: View {
var title: String = ""
var icon: String = ""
var color: Color = .red
var page: Page
#Binding var macMainVM :Page
var body: some View {
Button(action: {
withAnimation(.spring(response: 0.5, dampingFraction: 0.6, blendDuration: 0)) {
self.macMainVM = self.page
}
}) {
VStack {
Text("Tap")
.font(.custom("Oswald-Light", size: 14))
.fixedSize()
}
.padding(5)
//I emphasize the choice here
.background(self.macMainVM == self.page ? RoundedRectangle(cornerRadius: 10).stroke(color) : nil)
}
.buttonStyle(PlainButtonStyle())
}
}
struct mainView:View{
let basicCategory = [
Category(title: "En Yeniler", icon: "flame", color: .red, page: .newest),
Category(title: "Popüler", icon: "star", color: .yellow, page: .populer),
]
#ObservedObject var macMainVM = MainViewModel()
var body: some View {
VStack {
ForEach(basicCategory.indices) { index in
TabView(page: basicCategory[index].page,macMainVM: $macMainVM.selectedTab)
}
}
}
}
Multiple Selection
import SwiftUI
enum Page:String {
case newest
case populer
case iPhone
case iPad
case mac
case watch
}
class MainViewModel: ObservableObject {
#Published var selectedTab = Page.newest
var stateArray:[Bool] = []
}
struct Category: Identifiable {
var id = UUID()
var title: String
var icon: String
var color: Color
var page: Page
}
struct TabView: View {
var title: String = ""
var icon: String = ""
var color: Color = Color.red
var page: Page
var count = 0
var onIndex:Int
#ObservedObject var macMainVM = MainViewModel()
init(totalPage:Int,page:Page,onIndex:Int) {
self.count = totalPage
self.page = page
self.onIndex = onIndex
macMainVM.stateArray = [Bool](repeating: false, count: totalPage)
}
var body: some View {
Button(action: {
withAnimation(.spring(response: 0.5, dampingFraction: 0.6, blendDuration: 0)) {
if macMainVM.stateArray[onIndex] == false{
macMainVM.stateArray[onIndex] = true
}else{
macMainVM.stateArray[onIndex] = false
}
macMainVM.selectedTab = self.page
}
}) {
VStack {
Text("Tap")
.font(.custom("Oswald-Light", size: 14))
.fixedSize()
}
.padding(5)
//I emphasize the choice here
.background(macMainVM.stateArray[onIndex] ? RoundedRectangle(cornerRadius: 10).stroke(color) : nil)
}
.buttonStyle(PlainButtonStyle())
}
}
struct mainView:View{
let basicCategory = [
Category(title: "En Yeniler", icon: "flame", color: .red, page: .newest),
Category(title: "Popüler", icon: "star", color: .yellow, page: .populer),
]
//var model = MainViewModel()
var body: some View {
VStack {
ForEach(basicCategory.indices) { index in
TabView(totalPage: basicCategory.count, page: basicCategory[index].page, onIndex: index)
}
}
}
}
NOTE-: I haven’t explained what I did in deep, because it will be more understandable by looking into code.

Answer 3

The most Easy way: You should just use shared object, which you are creating new one every time! I did not edit your code! I just used a shared model! that was all I done! Or you can use environmentObject, and that would also solve the issue without shared one! both way is working!
import SwiftUI
struct ContentView: View {
var body: some View {
VStack {
ForEach(basicCategory, id: \.id) { item in
TabView(title: item.title, icon: item.icon, color: item.color, page: item.page)
}
}
.background(Color.gray)
}
}
enum Page {
case newest
case populer
case iPhone
case iPad
case mac
case watch
}
class MainViewModel: ObservableObject {
static let shared: MainViewModel = MainViewModel() // <<: Here
#Published var selectedTab = Page.newest
}
struct Category: Identifiable {
var id = UUID()
var title: String
var icon: String
var color: Color
var page: Page
}
let basicCategory = [
Category(title: "En Yeniler", icon: "flame", color: .red, page: .newest),
Category(title: "Popüler", icon: "star", color: .yellow, page: .populer),
Category(title: "iPhone", icon: "iphone.homebutton", color: .yellow, page: .iPhone),
Category(title: "ipad", icon: "ipad.homebutton", color: .yellow, page: .iPad),
]
struct TabView: View {
let title: String
let icon: String
let color: Color
let page: Page
#ObservedObject var macMainVM = MainViewModel.shared // <<: Here
var body: some View {
Button(action: {
withAnimation(.spring(response: 0.5, dampingFraction: 0.6, blendDuration: 0)) {
macMainVM.selectedTab = page
}
}) {
VStack {
Image(systemName: icon)
.imageScale(.large)
.foregroundColor(color)
Text(title)
.font(.custom("Oswald-Light", size: 14))
.fixedSize()
}
.padding(5)
.background(macMainVM.selectedTab == page ? RoundedRectangle(cornerRadius: 10).stroke(color) : nil)
}
.buttonStyle(PlainButtonStyle())
}
}