Using HalfASheet (https://github.com/franklynw/HalfASheet).
I have a View called ProjectsView, and in the ZStack in ProjectsView I have ProjectSorting and SortingView(both injected with the EnvironmentObject). I want the Text(🟩) in ProjectSorting to be changed, and the HStack(🟦) in SortingView to have a checkmark, both depending on the value of the sorting variable in SortingValues. Users can change the value of the sorting by pressing the Button in SortingView.
For whatever reason, the Text(🟩) in ProjectSorting does not change at all. And the HStack(🟦) in SortingView only gets the checkmark when its ancestor stack has another Text(🟨) which includes the #State variable from the environment, which I find very weird.
What should I change? Is there any way I can make this work using #EnvironmentObject? I'm a newbie and couldn't really understand other wrappers so I'd like to make this work within #State, #Binding, #EnvirionmentObject.
Thanks in advance.
SortingValues.swift
import Combine
class SortingValues: ObservableObject {
#Published var sorting = "Top Rated"
}
ProjectsView.swift
struct ProjectsView: View {
#Binding var isPresented: Bool
#State var showSortingSheet = false
var body: some View {
ZStack {
NavigationView {
VStack(spacing: 0) {
ProjectsTopView(isPresented: $isPresented)
ProjectSorting(showSortingSheet: $showSortingSheet)
.environmentObject(SortingValues())
ProjectList()
}
.navigationBarHidden(true)
}
SortingView(showSortingSheet: $showSortingSheet)
.environmentObject(SortingValues())
}
}
}
ProjectSorting.swift
import SwiftUI
struct ProjectSorting: View {
#EnvironmentObject var sortingValues: SortingValues
#Binding var showSortingSheet: Bool
#State var sortingValue = ""
var body: some View {
VStack {
HStack {
Text("Projects")
Spacer()
Button {
showSortingSheet.toggle()
} label: {
HStack(spacing: 3) {
Image("sortingArrows")
Text(sortingValue) // < 🟩 this is the Text I want to be changed
}
}
}
// Another HStack goes here
}
.onReceive(sortingValues.$sorting) { sorting in
print("This is ProjectSorting. sorting:", sorting) // < this does not print when I close the half sheet
sortingValue = sorting
}
}
}
SortingView.swift
import SwiftUI
import HalfASheet
struct SortingView: View {
#EnvironmentObject var sortingValues: SortingValues
#Binding var showSortingSheet: Bool
#State var sortingValue = ""
var body: some View {
VStack {
HalfASheet(isPresented: $showSortingSheet) {
let sorting = ["Most Recent", "Most Reviewed", "Top Rated", "Lowest Price", "Highest Price"]
VStack(alignment: .leading) {
ForEach(sorting, id: \.self) { sorting in
VStack(alignment: .leading, spacing: 14) {
Button (action: {
sortingValues.sorting = sorting
}, label: {
HStack { // 🟦
Text(sorting)
Spacer()
if sorting == sortingValue { // < this is where I add the checkmark
Image(systemName: "checkmark")
}
}
.foregroundColor(.primary)
})
if sorting != "Highest Price" {
Divider()
}
}
}
}
}
.height(.fixed(325))
// Text("Inside VStack, outside HalfASheet") // adding this Text DOES NOT make the HStack have a checkmark
Text("Inside VStack, outside HalfASheet: \(sortingValue)") // 🟨 adding this Text DOES make the HStack have a checkmark
}
.onReceive(sortingValues.$sorting) { sorting in
// the two printing lines below print correctly every time I tap the Button
print("This is SortingView. sorting:", sorting)
print("sortingValues.sorting: \(sortingValues.sorting)")
sortingValue = sorting
}
}
}
Your SortingView and ProjectSorting both access an environment object of type SortingValues, but you're passing new, separate instances to each. So the change you make in one place isn't being reflected in the other, because each view is communicating with one of two completely different objects of the same type.
If you want them to interact with the same object instance, you need to declare it at a point that's above both in the object hierarchy and make sure that that single instance is passed into both. For example:
struct ProjectsView: View {
#Binding var isPresented: Bool
#State var showSortingSheet = false
#StateObject var sortingValues = SortingValues()
var body: some View {
ZStack {
NavigationView {
VStack(spacing: 0) {
ProjectsTopView(isPresented: $isPresented)
ProjectSorting(showSortingSheet: $showSortingSheet)
.environmentObject(sortingValue)
ProjectList()
}
.navigationBarHidden(true)
}
SortingView(showSortingSheet: $showSortingSheet)
.environmentObject(sortingValues)
}
}
}
But you can go one step further. Because environment objects and values propagate down the view hierarchy automatically, you can replace two separate .environmentObject calls with one:
struct ProjectsView: View {
#Binding var isPresented: Bool
#State var showSortingSheet = false
#StateObject var sortingValues = SortingValues()
var body: some View {
ZStack {
NavigationView {
VStack(spacing: 0) {
ProjectsTopView(isPresented: $isPresented)
ProjectSorting(showSortingSheet: $showSortingSheet)
ProjectList()
}
.navigationBarHidden(true)
}
SortingView(showSortingSheet: $showSortingSheet)
}
.environmentObject(sortingValues)
}
}
There are probably better ways of dealing with reacting to changes in your observed model rather than duplicating variable values in a local state variable -- but ensuring that all your views are using the same shared environment object should get you on your way.
Set property wrapper to pop view "#Environment(.presentationMode) var presentationMode" but it is reloading view again and again. Why it is happening? any solution?
What i have observed except #Environment(.presentationMode) we should use bool value binding with controller, Please check code:
struct newView: View {
#State private var isActiveView: Bool = false
var body: some View {
VStack(alignment: .center) {
NavigationLink(destination: PushedView(isActiveView: $isActiveView), isActive: $isActiveView) {
Text("Create Account")
}
}
}
}
And on pushed screen check the code:
`struct PushedView: View {
#Binding var isActiveView: Bool
var body: some View {
NavigationView {
VStack {
Text(“Back”).onTapGesture {
isActiveView = false // to pop into previous view
}
}
}
}
}
`
I have a NavigationView which is showing a different view via fullScreenCover when I press a Button. Now I need to know when my view from where I pressed the Button is getting visible again and what was the view before. In the view shown by the fullScreenCover im using #Environment(\.dismiss) var dismiss to dismiss it.
So here is my concrete use case:
I have my main screen with two Buttons A and B.
A is showing sub view 1 and B is showing sub view 2.
When I dismiss one of these sub screens I need to know if I was in A view 1 or 2 before.
Is this somehow possible?
You can use the .onDisappear on the view that is linked on the destination of the NavigationLink. See this example:
import SwiftUI
struct ContentView: View {
#State var selectedSubView: ViewSelection = ViewSelection.zero
var body: some View {
NavigationView {
VStack {
// Version 1
NavigationLink (
destination: SubView1()
.onDisappear {
self.selectedSubView = .one
print(self.selectedSubView) // debug
},
label: {
Text("To ViewOne").padding()
})
// Version 2
NavigationLink (
destination: SubView2()
.onDisappear {
self.selectedSubView = .two
print(self.selectedSubView) // debug
},
label: {
Text("To ViewTwo")
.padding()
})
}
}
}
}
struct SubView1: View {
var body: some View {
Text("View 1")
}
}
struct SubView2: View {
var body: some View {
Text("View 2")
}
}
enum ViewSelection {
case one
case two
case zero
}
You can use .fullScreenCover with an onDismiss closure.
(Here I used .sheet because it's easier to test, but it's the same)
struct SwiftUIView4: View {
#State private var destination: Destination?
#State private var showed: Destination?
#State private var dismissed: Destination?
var body: some View {
VStack {
HStack {
Button("A") {
destination = .firstView
showed = .firstView
}.padding()
Spacer()
Button("B") {
destination = .secondView
showed = .secondView
}.padding()
}
Text("Just dismissed : \(dismissed?.rawValue ?? "nothing")")
.sheet(item: $destination, onDismiss: {
dismissed = showed
}, content: { destination in
switch destination {
case .firstView: Text("A clicked")
case .secondView: Text("B clicked")
}
})
}
}
}
enum Destination: String, Identifiable {
case firstView, secondView
var id: Destination { self }
}
Or you could use a custom Binding for the item parameter of your .fullScreenCover :
struct SwiftUIView4: View {
#State private var showed: Destination?
#State private var dismissed: Destination?
var body: some View {
VStack {
HStack {
Button("A") {
showed = .firstView
}.padding()
Spacer()
Button("B") {
showed = .secondView
}.padding()
}
Text("Just dismissed : \(dismissed?.rawValue ?? "nothing")")
.sheet(item: .init(get: {showed}, set: {
dismissed = showed // HERE
showed = $0 // <<<<
})) { destination in
switch destination {
case .firstView: Text("A clicked")
case .secondView: Text("B clicked")
}
}
}
}
}
I'm new to SwiftUI and struggling to move MainView to LoginView by clicking Text() in ChildView.
I tried make NavigationView and NavigationLink like this code but it's not working. It's much more complex in real code but I show only simple structure of my code to explain.
struct ContentView: View {
#State private var currViewIdx: Int = 0
var body: some View {
NavigationView {
CurrentView(currViewIdx: $currViewIdx)
}
}
}
struct CurrentView: View {
#Binding var currViewIdx: Int
var body: some View {
if self.currViewIdx == 0 {
HomeView()
.onTapGesture {
self.currViewIdx = 0
}
} else {
//SomeView.onTapGesture(self.currViewIdx = 1)
}
}
}
struct HomeView: View {
var body: some View {
NavigationLink(destination: TestView()) {
Text("Go TestView")
.contentShape(Rectangle())
}
}
}
struct TestView: View {
var body: some View {
Text("Here is Test View")
}
}
I think, the top hierarchy view, ContentView, has NavigationView and it should be changed when I click Text("Go TestView") in HomeView because it's in NavagationLink.
But the ContentView is not changed to TestView although I touch Text("Go TestView"). How to solve this problem? I considered way to add one more State value to change top level view, but it seems not good if I'll make lots of more values
Thank you
I couldn't find any reference about any ways to make a pop or a dismiss programmatically of my presented view with SwiftUI.
Seems to me that the only way is to use the already integrated slide dow action for the modal(and what/how if I want to disable this feature?), and the back button for the navigation stack.
Does anyone know a solution?
Do you know if this is a bug or it will stays like this?
This example uses the new environment var documented in the Beta 5 Release Notes, which was using a value property. It was changed in a later beta to use a wrappedValue property. This example is now current for the GM version. This exact same concept works to dismiss Modal views presented with the .sheet modifier.
import SwiftUI
struct DetailView: View {
#Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>
var body: some View {
Button(
"Here is Detail View. Tap to go back.",
action: { self.presentationMode.wrappedValue.dismiss() }
)
}
}
struct RootView: View {
var body: some View {
VStack {
NavigationLink(destination: DetailView())
{ Text("I am Root. Tap for Detail View.") }
}
}
}
struct ContentView: View {
var body: some View {
NavigationView {
RootView()
}
}
}
SwiftUI Xcode Beta 5
First, declare the #Environment which has a dismiss method which you can use anywhere to dismiss the view.
import SwiftUI
struct GameView: View {
#Environment(\.presentationMode) var presentation
var body: some View {
Button("Done") {
self.presentation.wrappedValue.dismiss()
}
}
}
iOS 15+
Starting from iOS 15 we can use a new #Environment(\.dismiss):
struct SheetView: View {
#Environment(\.dismiss) var dismiss
var body: some View {
NavigationView {
Text("Sheet")
.toolbar {
Button("Done") {
dismiss()
}
}
}
}
}
(There's no more need to use presentationMode.wrappedValue.dismiss().)
Useful links:
DismissAction
There is now a way to programmatically pop in a NavigationView, if you would like. This is in beta 5. Notice that you don't need the back button. You could programmatically trigger the showSelf property in the DetailView any way you like. And you don't have to display the "Push" text in the master. That could be an EmptyView(), thereby creating an invisible segue.
import SwiftUI
struct ContentView: View {
var body: some View {
NavigationView {
MasterView()
}
}
}
struct MasterView: View {
#State private var showDetail = false
var body: some View {
VStack {
NavigationLink(destination: DetailView(showSelf: $showDetail), isActive: $showDetail) {
Text("Push")
}
}
}
}
struct DetailView: View {
#Binding var showSelf: Bool
var body: some View {
Button(action: {
self.showSelf = false
}) {
Text("Pop")
}
}
}
#if DEBUG
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
#endif
I recently created an open source project called swiftui-navigation-stack (https://github.com/biobeats/swiftui-navigation-stack) that contains the NavigationStackView, an alternative navigation stack for SwiftUI. It offers several features described in the readme of the repo. For example, you can easily push and pop views programmatically. I'll show you how to do that with a simple example:
First of all embed your hierarchy in a NavigationStackVew:
struct RootView: View {
var body: some View {
NavigationStackView {
View1()
}
}
}
NavigationStackView gives your hierarchy access to a useful environment object called NavigationStack. You can use it to, for instance, pop views programmatically as asked in the question above:
struct View1: View {
var body: some View {
ZStack {
Color.yellow.edgesIgnoringSafeArea(.all)
VStack {
Text("VIEW 1")
Spacer()
PushView(destination: View2()) {
Text("PUSH TO VIEW 2")
}
}
}
}
}
struct View2: View {
#EnvironmentObject var navStack: NavigationStack
var body: some View {
ZStack {
Color.green.edgesIgnoringSafeArea(.all)
VStack {
Text("VIEW 2")
Spacer()
Button(action: {
self.navStack.pop()
}, label: {
Text("PROGRAMMATICALLY POP TO VIEW 1")
})
}
}
}
}
In this example I use the PushView to trigger the push navigation with a tap. Then, in the View2 I use the environment object to programmatically come back.
Here is the complete example:
import SwiftUI
import NavigationStack
struct RootView: View {
var body: some View {
NavigationStackView {
View1()
}
}
}
struct View1: View {
var body: some View {
ZStack {
Color.yellow.edgesIgnoringSafeArea(.all)
VStack {
Text("VIEW 1")
Spacer()
PushView(destination: View2()) {
Text("PUSH TO VIEW 2")
}
}
}
}
}
struct View2: View {
#EnvironmentObject var navStack: NavigationStack
var body: some View {
ZStack {
Color.green.edgesIgnoringSafeArea(.all)
VStack {
Text("VIEW 2")
Spacer()
Button(action: {
self.navStack.pop()
}, label: {
Text("PROGRAMMATICALLY POP TO VIEW 1")
})
}
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
RootView()
}
}
the result is:
Alternatively, if you don't want to do it programatically from a button, you can emit from the view model whenever you need to pop.
Subscribe to a #Published that changes the value whenever the saving is done.
struct ContentView: View {
#ObservedObject var viewModel: ContentViewModel
#Environment(\.presentationMode) var presentationMode
init(viewModel: ContentViewModel) {
self.viewModel = viewModel
}
var body: some View {
Form {
TextField("Name", text: $viewModel.name)
.textContentType(.name)
}
.onAppear {
self.viewModel.cancellable = self.viewModel
.$saved
.sink(receiveValue: { saved in
guard saved else { return }
self.presentationMode.wrappedValue.dismiss()
}
)
}
}
}
class ContentViewModel: ObservableObject {
#Published var saved = false // This can store any value.
#Published var name = ""
var cancellable: AnyCancellable? // You can use a cancellable set if you have multiple observers.
func onSave() {
// Do the save.
// Emit the new value.
saved = true
}
}
Please check Following Code it's so simple.
FirstView
struct StartUpVC: View {
#State var selection: Int? = nil
var body: some View {
NavigationView{
NavigationLink(destination: LoginView().hiddenNavigationBarStyle(), tag: 1, selection: $selection) {
Button(action: {
print("Signup tapped")
self.selection = 1
}) {
HStack {
Spacer()
Text("Sign up")
Spacer()
}
}
}
}
}
SecondView
struct LoginView: View {
#Environment(\.presentationMode) var presentationMode
var body: some View {
NavigationView{
Button(action: {
print("Login tapped")
self.presentationMode.wrappedValue.dismiss()
}) {
HStack {
Image("Back")
.resizable()
.frame(width: 20, height: 20)
.padding(.leading, 20)
}
}
}
}
}
You can try using a custom view and a Transition.
Here's a custom modal.
struct ModalView<Content>: View where Content: View {
#Binding var isShowing: Bool
var content: () -> Content
var body: some View {
GeometryReader { geometry in
ZStack(alignment: .center) {
if (!self.isShowing) {
self.content()
}
if (self.isShowing) {
self.content()
.disabled(true)
.blur(radius: 3)
VStack {
Text("Modal")
}
.frame(width: geometry.size.width / 2,
height: geometry.size.height / 5)
.background(Color.secondary.colorInvert())
.foregroundColor(Color.primary)
.cornerRadius(20)
.transition(.moveAndFade) // associated transition to the modal view
}
}
}
}
}
I reused the Transition.moveAndFade from the Animation Views and Transition tutorial.
It is defined like this:
extension AnyTransition {
static var moveAndFade: AnyTransition {
let insertion = AnyTransition.move(edge: .trailing)
.combined(with: .opacity)
let removal = AnyTransition.scale()
.combined(with: .opacity)
return .asymmetric(insertion: insertion, removal: removal)
}
}
You can test it - in the simulator, not in the preview - like this:
struct ContentView: View {
#State var isShowingModal: Bool = false
func toggleModal() {
DispatchQueue.main.asyncAfter(deadline: .now() + 3) {
withAnimation {
self.isShowingModal = true
}
DispatchQueue.main.asyncAfter(deadline: .now() + 3) {
withAnimation {
self.isShowingModal = false
}
}
}
}
var body: some View {
ModalView(isShowing: $isShowingModal) {
NavigationView {
List(["1", "2", "3", "4", "5"].identified(by: \.self)) { row in
Text(row)
}.navigationBarTitle(Text("A List"), displayMode: .large)
}.onAppear { self.toggleModal() }
}
}
}
Thanks to that transition, you will see the modal sliding in from the trailing edge, and the it will zoom and fade out when it is dismissed.
The core concept of SwiftUI is to watch over the data flow.
You have to use a #State variable and mutate the value of this variable to control popping and dismissal.
struct MyView: View {
#State
var showsUp = false
var body: some View {
Button(action: { self.showsUp.toggle() }) {
Text("Pop")
}
.presentation(
showsUp ? Modal(
Button(action: { self.showsUp.toggle() }) {
Text("Dismiss")
}
) : nil
)
}
}
I experienced a compiler issue trying to call value on the presentationMode binding. Changing the property to wrappedValue fixed the issue for me. I'm assuming value -> wrappedValue is a language update. I think this note would be more appropriate as a comment on Chuck H's answer but don't have enough rep points to comment, I also suggested this change as and edit but my edit was rejected as being more appropriate as a comment or answer.
This will also dismiss the view
let scenes = UIApplication.shared.connectedScenes
let windowScene = scenes.first as? UIWindowScene
let window = windowScene?.windows.first
window?.rootViewController?.dismiss(animated: true, completion: {
print("dismissed")
})