I'm trying to present a modal within a List. Modals have changed many times in the betas, but I believe I'm using the correct/latest way (as of Xcode Beta 7). However, when I'm triggering the modal from within a list, for each list item it opens once but then never again.
import SwiftUI
//This works perfectly fine
struct BasicTest : View {
struct SampleObject: Identifiable {
var id = UUID()
var name: String
}
let sampleObjects = [
SampleObject(name: "Buffalo"),
SampleObject(name: "Italy"),
SampleObject(name: "Portland"),
]
#State private var showModal:Bool = false
var body: some View {
Button(action: {
print("Modal to open")
self.showModal = true
}) {
Text("Show Modal")
}.sheet(isPresented: self.$showModal)
{
TestDetailView(name: "Example")
}
}
}
#if DEBUG
struct BasicTest_Previews: PreviewProvider {
static var previews: some View {
BasicTest()
}
}
#endif
//this one only opens once
struct ListTest : View {
struct SampleObject: Identifiable {
var id = UUID()
var name: String
}
let sampleObjects = [
SampleObject(name: "Buffalo"),
SampleObject(name: "Italy"),
SampleObject(name: "Portland"),
]
#State private var showModal:Bool = false
var body: some View {
List {
ForEach(sampleObjects) {
item in
Button(action: {
print("Modal to open")
self.showModal = true
}) {
Text("Show Modal for \(item.name)")
}.sheet(isPresented: self.$showModal)
{
TestDetailView(name: item.name)
}
}
}
}
}
#if DEBUG
struct ListTest_Previews: PreviewProvider {
static var previews: some View {
ListTest()
}
}
#endif
struct TestDetailView: View {
#Environment(\.presentationMode) var presentationMode
var name: String
var body: some View {
VStack {
Button(action: {
print("Button clicked")
self.presentationMode.wrappedValue.dismiss()
}) {
Image(systemName: "chevron.compact.down").font(Font.system(.largeTitle).bold())
}
Text(name)
}
}
}
No error messages exist that I can see, just a flash when trying to open a second time.
It’ll work if you create a view for list row and move .sheet() there
Related
I am facing an issue while popping to a specific view. Let me explain the hierarchy.
ContentView -> 2 tabs, TabAView and TabBView
Inside TabBView. There is 1 view used ConnectView: Where is a Button to connect. After tapping on the button of Connect, the user move to another View which is called as UserAppView. From Here User can check his profile and update also. After the Update API call, need to pop to UserAppView from UserFirstFormView.
Here is the code to understand better my problem.
ContentView.swift
struct ContentView: View {
enum AppPage: Int {
case TabA=0, TabB=1
}
#StateObject var settings = Settings()
#ObservedObject var userViewModel: UserViewModel
var body: some View {
NavigationView {
TabView(selection: $settings.tabItem) {
TabAView(userViewModel: userViewModel)
.tabItem {
Text("TabA")
}
.tag(AppPage.TabA)
TabBView(userViewModel: userViewModel)
.tabItem {
Text("Apps")
}
.tag(AppPage.TabB)
}
.accentColor(.white)
.edgesIgnoringSafeArea(.top)
.onAppear(perform: {
settings.tabItem = .TabA
})
.navigationBarTitleDisplayMode(.inline)
}
.environmentObject(settings)
}
}
This is TabAView:
struct TabAView: View {
#ObservedObject var userViewModel: UserViewModel
#EnvironmentObject var settings: Settings
init(userViewModel: UserViewModel) {
self.userViewModel = userViewModel
}
var body: some View {
Vstack {
/// code
}
.onAppear(perform: {
/// code
})
.environmentObject(settings)
}
}
This is another TabBView:
struct TabBView: View {
#ObservedObject var userViewModel: UserViewModel
init(userViewModel: UserViewModel) {
self.userViewModel = userViewModel
}
var body: some View {
VStack (spacing: 10) {
NavigationLink(destination: ConnectView(viewModel: ConnectViewModel(id: id!), userViewModel: userViewModel)) {
UserCardWidget()
}
}
}
}
There is 1 connectView used on the TabBView through which the user will connect. ConnectViewModel is used here to call connect API.
class ConnectViewModel: ObservableObject {
var id: String?
init(id: String) {
self.id = id
}
func connect(completion: #escaping () -> Void) {
APIService.shared.connectApp(id: self.id!) { connected in
DispatchQueue.main.async {
self.isConnected = connected ?? false
completion()
}
}
}
}
This is connect view
struct ConnectView: View {
#ObservedObject var connectViewModel: ConnectViewModel
#ObservedObject var userViewModel: UserViewModel
#State var buttonTitle = "CONNECT WITH THIS"
#State var isShowingDetailView = false
var body: some View {
VStack {
Spacer()
if let id = connectViewModel.id {
NavigationLink(destination: UserAppView(id: id, userViewModel: userViewModel), isActive: $isShowingDetailView) {
Button(buttonTitle, action: {
connectViewModel.connect {
buttonTitle = "CONNECTED"
isShowingDetailView = true
}
})
}
}
}
}
}
This is the UserAppViewModel where API is hit to fetch some user-related details:
class UserAppViewModel: ObservableObject {
var id = ""
func getdetails() {
APIService.shared.getDetails() { userDetails in
DispatchQueue.main.async {
/// code
}
}
}
}
This is UserAppView class
struct UserAppView: View {
#ObservedObject var userViewModel: UserViewModel
#State private var signUpInButtonClicked: Bool = false
#StateObject private var userAppViewModel = UserAppViewModel()
init(id: String, userViewModel: UserViewModel) {
self.id = id
self.userViewModel = userViewModel
}
var body: some View {
VStack {
Text(userAppViewModel.status)
VStack {
Spacer()
NavigationLink(
destination: ProfileView(userAppViewModel: userAppViewModel, isActive: $signUpInButtonClicked)) { EmptyView() }
if /// Condition {
Button(action: {
signUpInButtonClicked = true
}, label: {
ZStack {
/// code
}
.frame(maxWidth: 77, maxHeight: 25)
})
}
}.onAppear(perform: {
**userAppViewModel.getDetails**(id: id)
})
}
}
From Here, the User Can Navigate to ProfileView.
struct ProfileUpdateView: View {
#State private var navigationSelectionFirstFormView = false
#State private var navigationSelectionLastFormView = false
public var body: some View {
VStack {
NavigationLink(destination: UserFirstFormView(userAppViewModel: userAppViewModel), isActive: $navigationSelectionFirstFormView) {
EmptyView()
}
NavigationLink(destination: UserLastFormView(userAppViewModel: userAppViewModel), isActive: $navigationSelectionLastFormView) {
EmptyView()
}
}
.navigationBarItems(trailing: Button(action: {
if Condition {
navigationSelectionFirstFormView = true
} else {
navigationSelectionLastFormView = true
}
}, label: {
HStack {
Text("Action")
.foregroundColor(Color.blue)
}
})
)
}
}
Further, their user will move to the next screen to update the profile.
struct UserFirstFormView: View {
var body: some View {
VStack {
/// code
///
Button("buttonTitle", action: {
API Call completion: { status in
if status {
self.rootPresentationMode.wrappedValue.dismiss()
}
})
})
.frame(maxHeight: 45)
}
}
}
I am trying to pop from this view once the API response is received but nothing is working.
I have removed most of the code from a confidential point of view but this code will explain the reason and error. Please look into the code and help me.
You could use the navigation link with, tag: and selection: overload and let the viewmodel control what link is open, here a example
enum profileViews {
case view1
case view2}
in your viewModel add an published var that will hold the active view
#Published var activeView: profileViews?
then in your navigation link you can do it like this
NavigationLink(
destination: secondView(profileViewModel: ProfileViewModel ),
tag: profileViews.view1,
selection: self.$profileViewModel.activeView
){}
Then you could pop any view just updating the variable inside the view model
self.profileViewModel.activeView = nil
how to navigate out of a ActionSheet where I can only Pass a Text but not a NavigationLink?
Sample Code:
struct DemoActionSheetNavi: View {
#State private var showingSheet = false
var body: some View {
NavigationView {
Text("Test")
.actionSheet(isPresented: $showingSheet) {
ActionSheet(
title: Text("What do you want to do?"),
message: Text("There's only one choice..."),
buttons: [
.default(Text("How to navigate from here to HelpView???")),
])
}
}
}
}
You would need something like this:
struct DemoActionSheetNavi: View {
#State private var showingSheet = false
#State private var showingHelp = false
var body: some View {
NavigationView {
VStack {
Text("Test")
Button("Tap me") { self.showingSheet = true }
NavigationLink(destination: HelpView(isShowing: $showingHelp),
isActive: $showingHelp) {
EmptyView()
}
}
}
.actionSheet(isPresented: $showingSheet) {
ActionSheet(
title: Text("What do you want to do?"),
message: Text("There's only one choice..."),
buttons: [.cancel(),
.default(Text("Go to help")) {
self.showingSheet = false
self.showingHelp = true
}])
}
}
}
You have another state that programmatically triggers a NavigationLink (you could also do it using .sheet and modal presentation). You would also need to pass showingHelp as a #Binding to help view to be able to reset it.
struct HelpView: View {
#Binding var isShowing: Bool
var body: some View {
Text("Help view")
.onDisappear() { self.isShowing = false }
}
}
The code for the basic app from Anlil's answer works fine. If I edit the datamodel to be more like mine, with a multidimensional String array, I get something like:
import SwiftUI
import Combine
struct ContentView: View {
#EnvironmentObject var dm: DataManager
var body: some View {
NavigationView {
List {
NavigationLink(destination:AddView().environmentObject(self.dm)) {
Image(systemName: "plus.circle.fill").font(.system(size: 30))
}
ForEach(dm.array, id: \.self) { item in
NavigationLink(destination: DetailView(item: item)) {
Text(item[0])
}
}
}
}
}
}
struct DetailView: View {
var item : [String] = ["", "", ""]
var body: some View {
VStack {
Text(item[0])
Text(item[1])
Text(item[2])
}
}
}
struct AddView: View {
#EnvironmentObject var dm: DataManager
#State var item0 : String = "" // needed by TextField
#State var item1 : String = "" // needed by TextField
#State var item2 : String = "" // needed by TextField
#State var item : [String] = ["", "", ""]
var body: some View {
VStack {
TextField("Write something", text: $item0)
.textFieldStyle(.roundedBorder)
.padding(.horizontal)
TextField("Write something", text: $item1)
.textFieldStyle(.roundedBorder)
.padding(.horizontal)
TextField("Write something", text: $item2)
.textFieldStyle(.roundedBorder)
.padding(.horizontal)
Button(action: {
self.item = [self.item0, self.item1, self.item2]
print(self.item)
self.dm.array.append(self.item)
}) {
Text("Save")
}
}
}
}
class DataManager: BindableObject {
var willChange = PassthroughSubject<Void, Never>()
var array : [[String]] = [["Item 1","Item 2","Item 3"],["Item 4","Item 5","Item 6"],["Item 7","Item 8","Item 9"]] {
didSet {
willChange.send()
}
}
}
There are no errors and the code runs as expected. Before I'm going to rewrite my own code (with the lessons I've learned solar) it would be nice if the code could be checked.
I'm really impressed with SwiftUI!
If your "source of truth" is an array of some "model instances", and you just need to read values, you can pass those instance around like before:
import SwiftUI
import Combine
struct ContentView: View {
#EnvironmentObject var dm: DataManager
var body: some View {
NavigationView {
List(dm.array, id: \.self) { item in
NavigationLink(destination: DetailView(item: item)) {
Text(item)
}
}
}
}
}
struct DetailView: View {
var item : String
var body: some View {
Text(item)
}
}
class DataManager: BindableObject {
var willChange = PassthroughSubject<Void, Never>()
let array = ["Item 1", "Item 2", "Item 3"]
}
#if DEBUG
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView().environmentObject(DataManager())
}
}
#endif
You need to pass the EnvironmentObject only if some views are able to manipulate the data inside the instances... in this case you can easily update the EnvironmentObject's status and everything will auto-magically updated everywhere!
The code below shows a basic App with "list", "detail" and "add", so you can see 'environment' in action (the only caveat is that you have to manually tap < Back after tapped the Save button). Try it and you'll see the list that will magically update.
import SwiftUI
import Combine
struct ContentView: View {
#EnvironmentObject var dm: DataManager
var body: some View {
NavigationView {
List {
NavigationLink(destination:AddView().environmentObject(self.dm)) {
Image(systemName: "plus.circle.fill").font(.system(size: 30))
}
ForEach(dm.array, id: \.self) { item in
NavigationLink(destination: DetailView(item: item)) {
Text(item)
}
}
}
}
}
}
struct DetailView: View {
var item : String
var body: some View {
Text(item)
}
}
struct AddView: View {
#EnvironmentObject var dm: DataManager
#State var item : String = "" // needed by TextField
var body: some View {
VStack {
TextField("Write something", text: $item)
.textFieldStyle(.roundedBorder)
.padding(.horizontal)
Button(action: {
self.dm.array.append(self.item)
}) {
Text("Save")
}
}
}
}
class DataManager: BindableObject {
var willChange = PassthroughSubject<Void, Never>()
var array : [String] = ["Item 1", "Item 2", "Item 3"] {
didSet {
willChange.send()
}
}
}
#if DEBUG
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView().environmentObject(DataManager())
}
}
#endif
I'm trying to implement a dismiss button for my modal sheet as follows:
struct TestView: View {
#Environment(\.isPresented) var present
var body: some View {
Button("return") {
self.present?.value = false
}
}
}
struct DataTest : View {
#State var showModal: Bool = false
var modal: some View {
TestView()
}
var body: some View {
Button("Present") {
self.showModal = true
}.sheet(isPresented: $showModal) {
self.modal
}
}
}
But the return button when tapped does nothing. When the modal is displayed the following appears in the console:
[WindowServer] display_timer_callback: unexpected state (now:5fbd2efe5da4 < expected:5fbd2ff58e89)
If you force unwrap present you find that it is nil
How can I dismiss .sheet programmatically?
iOS 15+
Starting from iOS 15 we can use DismissAction that can be accessed as #Environment(\.dismiss).
There's no more need to use presentationMode.wrappedValue.dismiss().
struct SheetView: View {
#Environment(\.dismiss) var dismiss
var body: some View {
NavigationView {
Text("Sheet")
.toolbar {
Button("Done") {
dismiss()
}
}
}
}
}
Use presentationMode from the #Environment.
Beta 6
struct SomeView: View {
#Environment(\.presentationMode) var presentationMode
var body: some View {
VStack {
Text("Ohay!")
Button("Close") {
self.presentationMode.wrappedValue.dismiss()
}
}
}
}
For me, beta 4 broke this method - using the Environment variable isPresented - of using a dismiss button. Here's what I do nowadays:
struct ContentView: View {
#State var showingModal = false
var body: some View {
Button(action: {
self.showingModal.toggle()
}) {
Text("Show Modal")
}
.sheet(
isPresented: $showingModal,
content: { ModalPopup(showingModal: self.$showingModal) }
)
}
}
And in your modal view:
struct ModalPopup : View {
#Binding var showingModal:Bool
var body: some View {
Button(action: {
self.showingModal = false
}) {
Text("Dismiss").frame(height: 60)
}
}
}
Apple recommend (in WWDC 2020 Data Essentials in SwiftUI) using #State and #Binding for this. They also place the isEditorPresented boolean and the sheet's data in the same EditorConfig struct that is declared using #State so it can be mutated, as follows:
import SwiftUI
struct Item: Identifiable {
let id = UUID()
let title: String
}
struct EditorConfig {
var isEditorPresented = false
var title = ""
var needsSave = false
mutating func present() {
isEditorPresented = true
title = ""
needsSave = false
}
mutating func dismiss(save: Bool = false) {
isEditorPresented = false
needsSave = save
}
}
struct ContentView: View {
#State var items = [Item]()
#State private var editorConfig = EditorConfig()
var body: some View {
NavigationView {
Form {
ForEach(items) { item in
Text(item.title)
}
}
.navigationTitle("Items")
.toolbar {
ToolbarItem(placement: .primaryAction) {
Button(action: presentEditor) {
Label("Add Item", systemImage: "plus")
}
}
}
.sheet(isPresented: $editorConfig.isEditorPresented, onDismiss: {
if(editorConfig.needsSave) {
items.append(Item(title: editorConfig.title))
}
}) {
EditorView(editorConfig: $editorConfig)
}
}
}
func presentEditor() {
editorConfig.present()
}
}
struct EditorView: View {
#Binding var editorConfig: EditorConfig
var body: some View {
NavigationView {
Form {
TextField("Title", text:$editorConfig.title)
}
.toolbar {
ToolbarItem(placement: .confirmationAction) {
Button(action: save) {
Text("Save")
}
.disabled(editorConfig.title.count == 0)
}
ToolbarItem(placement: .cancellationAction) {
Button(action: dismiss) {
Text("Dismiss")
}
}
}
}
}
func save() {
editorConfig.dismiss(save: true)
}
func dismiss() {
editorConfig.dismiss()
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView(items: [Item(title: "Banana"), Item(title: "Orange")])
}
}
This looks like a very simple thing, but I can't figure out how to do this:
I have a List embedded in a NavigationView, containing a NavigationLink to view the detail of the item.
I have a save bar button where I would like to save the selected item. But how can I access the selected item?
It isn't visible in the button's action closure.
struct ItemList : View {
#EnvironmentObject var items: ItemsModel
var body: some View {
NavigationView {
List(items) { item in
NavigationLink(destination: ItemDetail(item: item)) {
Text(item.name)
}
}
.navigationBarTitle(Text("Item"))
.navigationBarItems(trailing: Button(action: {
self.save(/*item: item */) // How can I access item here?
}, label: {
Text("Save")
}))
}
}
func save(item: Item) {
print("Saving...")
}
}
Navigation links are not obligatory to accomplish this.
import SwiftUI
struct ContentView: View {
struct Ocean: Identifiable, Hashable {
let name: String
var id: Self { self }
}
private var oceans = [
Ocean(name: "Pacific"),
Ocean(name: "Atlantic"),
Ocean(name: "Indian"),
Ocean(name: "Southern"),
Ocean(name: "Arctic")
]
#State private var selectedOceans = [Ocean]()
#State private var multiSelection = Set<Ocean.ID>()
var body: some View {
VStack {
Text("Oceans")
List(oceans, selection: $multiSelection) {
Text($0.name)
}
.navigationTitle("Oceans")
.environment(\.editMode, .constant(.active))
.onTapGesture {
// Walkaround: try how it works without `asyncAfter()`
DispatchQueue.main.asyncAfter(deadline: .now() + 0.05, execute: {
selectedOceans = Array(multiSelection)
print(selectedOceans)
})
}
Divider()
Text("Selected oceans")
List(selectedOceans, selection: $multiSelection) {
Text($0.name)
}
}
Text("\(multiSelection.count) selections")
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}