SwiftUI Modal Inherits SearchBar during Sheet Presentation - ios

Consider the following example with a list and a button wrapped in a HStack that opens up a sheet:
struct ContentView: View {
#State var text: String = ""
#State var showSheet = false
var body: some View {
NavigationView {
List {
HStack {
button
}
Text("Hello World")
}
.searchable(text: $text)
}
}
var button: some View {
Button("Press", action: { showSheet = true })
.sheet(isPresented: $showSheet) {
modalView
}
}
var modalView: some View {
NavigationView {
List {
Text("Test")
}
}
}
}
On press of the button, a modal is presented to the user. However, the searchable modifier gets passed to the modal, see this video.
Now if the HStack is removed, everything works fine:
List {
button
Text("Hello World")
}
In addition, everything works also fine if the modal is not a NavigationView:
var modalView: some View {
List {
Text("Test")
}
}
Does somebody know what the problem here might be or is it once again one of those weird SwiftUI bugs?

putting the sheet, outside of the button and the List, works for me. I think .sheet is not meant to be inside a List, especially where searchable is operating.
struct ContentView: View {
#State var text: String = ""
#State var showSheet = false
var body: some View {
NavigationView {
List {
HStack {
button
}
Text("Hello World")
}
.searchable(text: $text)
}
.sheet(isPresented: $showSheet) {
modalView
}
}
var button: some View {
Button("Press", action: { showSheet = true })
}
var modalView: some View {
NavigationView {
List {
Text("Test")
}
}
}
}

Another workaround is to use navigationBarHidden = true, but then you must live without the navigation bar in the sheet view.
var modalView: some View {
NavigationView {
List {
Text("Test")
}
.navigationBarHidden(true)
}
}
Btw, on iPadOS it helps to use .searchable(text: $text, placement: .sidebar)

Related

Why is NavigationLink not working inside of a SwiftUI alert?

I have an alert that upon tapping I would like to return the user back to another view. The alert is showing, but why does it not navigate upon tapping?
VStack{
.alert("End of available content", isPresented: $model.alertIsPresented) {
NavigationLink(destination: SearchView()) {
Button("OK", role:.cancel) {}
}
}
}
Because NavigationLink needs to be inside of a hierarchy using NavigationView. An alert is a modal presented outside of that structure.
If you would like to programmatically navigate, you can use the isActive property of a NavigationLink within the NavigationView hierarchy.
struct ContentView : View {
#State private var alertIsPresented = false
#State private var navLinkActive = false
var body: some View {
NavigationView {
VStack{
Button("Present alert") {
alertIsPresented = true
}
.alert("End of available content", isPresented: $alertIsPresented) {
Button("Navigate") {
navLinkActive = true
}
}
NavigationLink(isActive: $navLinkActive, destination: { SearchView() }, label: {
EmptyView()
})
}
}
}
}
struct SearchView : View {
var body: some View {
Text("Search")
}
}

SwiftUI. Present a detail view pushed from the root view as the initial application view

I have two SwiftUI views, the first view has a navigation link to the second view and I want to show the second view that is "pushed" out of the first view, as the initial application view.
This is the behavior of the iOS Notes app, where users see a list of notes as the initial view controller and can return to the folder list with the back navigation button.
Can I implement this with SwiftUI and how?
Here is a simple demo. Prepared & tested with Xcode 11.7 / iOS 13.7
struct ContentView: View {
#State private var isActive = false
var body: some View {
NavigationView {
NavigationLink(destination: Text("Second View"), isActive: $isActive) {
Text("First View")
}
}
.onAppear { self.isActive = true }
}
}
you can add another state variable to hide the first view until the second view appears on the screen.
struct ContentView1: View {
#State private var isActive = false
#State private var showView = false
var body: some View {
NavigationView {
NavigationLink(destination: Text("Second View")
.onAppear {
self.showView = true
},
isActive: $isActive) {
if self.showView {
Text("First View")
} else {
EmptyView()
}
}
}
.onAppear {
self.isActive = true
}
}
}
As mentioned in my comments to another answer, by setting an initial state for a variable that controls the presentation of the second view to true, your ContentView presents this second view as the initial view.
I've tested this using the simulator and on device. This appears to solve your problem and does not present the transition from the first view to the second view to the user - app opens to the second view.
struct ContentView: View {
#State private var isActive = true
var body: some View {
NavigationView {
NavigationLink(destination: Text("Second View"), isActive: $isActive) {
Text("First View")
}
}
}
}
I made my own implementation based on #Asperi and #Mohammad Rahchamani answers.
This implementation allows you to navigate even from a list with multiple navigation links. Tested on Xcode 12 with SwiftUI 2.0.
struct IOSFolderListView: View {
#State var isActive = false
#State var wasViewShown = false
var body: some View {
let list = List {
NavigationLink(destination: Text("SecondView").onAppear {
self.wasViewShown = true
}, isActive: $isActive) {
Text("SecondView")
}
NavigationLink(destination: Text("ThirdView")) {
Text("ThirdView")
}
.onAppear {
self.isActive = false
}
}
if wasViewShown {
list.listStyle(GroupedListStyle())
.navigationBarTitle("FirstView")
.navigationBarItems(leading: Image(systemName: "folder.badge.plus"), trailing: Image(systemName: "square.and.pencil"))
} else {
list.opacity(0)
.onAppear {
self.isActive = true
}
}
}
}

SwiftUI transition from modal sheet to regular view with Navigation Link

I'm working with SwiftUI and I have a starting page. When a user presses a button on this page, a modal sheet pops up.
In side the modal sheet, I have some code like this:
NavigationLink(destination: NextView(), tag: 2, selection: $tag) {
EmptyView()
}
and my modal sheet view is wrapped inside of a Navigation View.
When the value of tag becomes 2, the view does indeed go to NextView(), but it's also presented as a modal sheet that the user can swipe down from, and I don't want this.
I'd like to transition from a modal sheet to a regular view.
Is this possible? I've tried hiding the navigation bar, etc. but it doesn't seem to make a difference.
Any help with this matter would be appreciated.
You can do this by creating an environmentObject and bind the navigationLink destination value to the environmentObject's value then change the value of the environmentObject in the modal view.
Here is a code explaining what I mean
import SwiftUI
class NavigationManager: ObservableObject{
#Published private(set) var dest: AnyView? = nil
#Published var isActive: Bool = false
func move(to: AnyView) {
self.dest = to
self.isActive = true
}
}
struct StackOverflow6: View {
#State var showModal: Bool = false
#EnvironmentObject var navigationManager: NavigationManager
var body: some View {
NavigationView {
ZStack {
NavigationLink(destination: self.navigationManager.dest, isActive: self.$navigationManager.isActive) {
EmptyView()
}
Button(action: {
self.showModal.toggle()
}) {
Text("Show Modal")
}
}
}
.sheet(isPresented: self.$showModal) {
secondView(isPresented: self.$showModal).environmentObject(self.navigationManager)
}
}
}
struct StackOverflow6_Previews: PreviewProvider {
static var previews: some View {
StackOverflow6().environmentObject(NavigationManager())
}
}
struct secondView: View {
#EnvironmentObject var navigationManager: NavigationManager
#Binding var isPresented: Bool
#State var dest: AnyView? = nil
var body: some View {
VStack {
Text("Modal view")
Button(action: {
self.isPresented = false
self.dest = AnyView(thirdView())
}) {
Text("Press me to navigate")
}
}
.onDisappear {
// This code can run any where but I placed it in `.onDisappear` so you can see the animation
if let dest = self.dest {
self.navigationManager.move(to: dest)
}
}
}
}
struct thirdView: View {
var body: some View {
Text("3rd")
.navigationBarTitle(Text("3rd View"))
}
}
Hope this helps, if you have any questions regarding this code, please let me know.

Dismiss a parent modal in SwiftUI from a NavigationView

I am aware of how to dismiss a modal from a child view using #Environment (\.presentationMode) var presentationMode / self.presentationMode.wrappedValue.dismiss() but this is a different issue.
When you present a multi-page NavigationView in a modal window, and have navigated through a couple of pages, the reference to presentationMode changes to be the NavigationView, so using self.presentationMode.wrappedValue.dismiss() simply pops the last NavigationView rather than dismissing the containing modal.
Is it possible - and if so how - to dismiss the containing modal from a page in a NavigationView tree?
Here's a simple example showing the problem. If you create an Xcode Single View app project using SwiftUI and replace the default ContentView code with this, it should work with no further changes.
import SwiftUI
struct ContentView: View {
#State var showModal: Bool = false
var body: some View {
Button(action: {
self.showModal.toggle()
}) {
Text("Launch Modal")
}
.sheet(isPresented: self.$showModal, onDismiss: {
self.showModal = false
}) {
PageOneContent()
}
}
}
struct PageOneContent: View {
var body: some View {
NavigationView {
VStack {
Text("I am Page One")
}
.navigationBarTitle("Page One")
.navigationBarItems(
trailing: NavigationLink(destination: PageTwoContent()) {
Text("Next")
})
}
}
}
struct PageTwoContent: View {
#Environment (\.presentationMode) var presentationMode
var body: some View {
NavigationView {
VStack {
Text("This should dismiss the modal. But it just pops the NavigationView")
.padding()
Button(action: {
// How to dismiss parent modal here instead
self.presentationMode.wrappedValue.dismiss()
}) {
Text("Finish")
}
.padding()
.foregroundColor(.white)
.background(Color.blue)
}
.navigationBarTitle("Page Two")
}
}
}
Here is possible approach based on usage own explicitly created environment key (actually I have feeling that it is not correct to use presentationMode for this use-case.. anyway).
Proposed approach is generic and works from any view in modal view hierarchy. Tested & works with Xcode 11.2 / iOS 13.2.
// define env key to store our modal mode values
struct ModalModeKey: EnvironmentKey {
static let defaultValue = Binding<Bool>.constant(false) // < required
}
// define modalMode value
extension EnvironmentValues {
var modalMode: Binding<Bool> {
get {
return self[ModalModeKey.self]
}
set {
self[ModalModeKey.self] = newValue
}
}
}
struct ParentModalTest: View {
#State var showModal: Bool = false
var body: some View {
Button(action: {
self.showModal.toggle()
}) {
Text("Launch Modal")
}
.sheet(isPresented: self.$showModal, onDismiss: {
}) {
PageOneContent()
.environment(\.modalMode, self.$showModal) // < bind modalMode
}
}
}
struct PageOneContent: View {
var body: some View {
NavigationView {
VStack {
Text("I am Page One")
}
.navigationBarTitle("Page One")
.navigationBarItems(
trailing: NavigationLink(destination: PageTwoContent()) {
Text("Next")
})
}
}
}
struct PageTwoContent: View {
#Environment (\.modalMode) var modalMode // << extract modalMode
var body: some View {
NavigationView {
VStack {
Text("This should dismiss the modal. But it just pops the NavigationView")
.padding()
Button(action: {
self.modalMode.wrappedValue = false // << close modal
}) {
Text("Finish")
}
.padding()
.foregroundColor(.white)
.background(Color.blue)
}
.navigationBarTitle("Page Two")
}
}
}
Another Approach would be to simply use a notification for this case and just reset the triggering flag for your modal.
It is not the most beautiful solution for me but it is the solution I am most likely to still understand in a few months.
import SwiftUI
struct ContentView: View {
#State var showModalNav: Bool = false
var body: some View {
Text("Present Modal")
.padding()
.onTapGesture {
showModalNav.toggle()
}.sheet(isPresented: $showModalNav, content: {
ModalNavView()
}).onReceive(NotificationCenter.default.publisher(for: Notification.Name(rawValue: "PushedViewNotifciation"))) { _ in
showModalNav = false
}
}
}
struct ModalNavView: View {
var body: some View {
NavigationView {
NavigationLink(
destination: PushedView(),
label: {
Text("Show Another View")
}
)
}
}
}
struct PushedView: View {
var body: some View {
Text("Pushed View").onTapGesture {
NotificationCenter.default.post(Notification.init(name: Notification.Name(rawValue: "PushedViewNotifciation")))
}
}
}
If you don't want to loosely couple the views through a notification you could also just use a binding for this like so:
struct ContentView: View {
#State var showModalNav: Bool = false
var body: some View {
Text("Present Modal")
.padding()
.onTapGesture {
showModalNav.toggle()
}.sheet(isPresented: $showModalNav, content: {
ModalNavView(parentShowModal: $showModalNav)
}).onReceive(NotificationCenter.default.publisher(for: Notification.Name(rawValue: "PushedViewNotifciation"))) { _ in
showModalNav = false
}
}
}
struct ModalNavView: View {
#Binding var parentShowModal: Bool
var body: some View {
NavigationView {
NavigationLink(
destination: PushedView(parentShowModal: $parentShowModal),
label: {
Text("Show Another View")
}
)
}
}
}
struct PushedView: View {
#Binding var parentShowModal: Bool
var body: some View {
Text("Pushed View").onTapGesture {
parentShowModal = false
}
}
}
If it's only two levels, and especially if you can dismiss the sheet at multiple levels, you could include showModal as a binding variable in your navigation views below, and then toggling it anywhere would dismiss the entire sheet.
I would assume you could do something similar with showModal as an EnvironmentObject as Wei mentioned above - which might be better if there are more than two levels and you only want to dismiss the sheet at the most specific level.
I can't remember if there's some reason to move away from doing this as a binding variable, but it seems to be working for me.
import SwiftUI
struct ContentView: View {
#State var showModal: Bool = false
var body: some View {
Button(action: {
self.showModal.toggle()
}) {
Text("Launch Modal")
}
.sheet(isPresented: self.$showModal, onDismiss: {
self.showModal = false
}) {
// Bind showModal to the corresponding property in PageOneContent
PageOneContent(showModal: $showModal)
}
}
}
Then you add showModal as a binding variable in PageOneContent, and it is bound to the state variable in ContentView.
struct PageOneContent: View {
// add a binding showModal var in here
#Binding var showModal: Bool
var body: some View {
NavigationView {
VStack {
Text("I am Page One")
}
.navigationBarTitle("Page One")
.navigationBarItems(
// bind showModal again to PageTwoContent
trailing: NavigationLink(destination: PageTwoContent(showModal: $showModal)) {
Text("Next")
})
}
}
}
Finally, in PageTwoContent, you can add showModal here (and in the NavigationLink in PageOneContent, you have bound PageTwoContent's showModal to PageOneContent). Then in your button, all you have to do is toggle it, and it will dismiss the sheet.
struct PageTwoContent: View {
// Add showModal as a binding var here too.
#Binding var showModal: Bool
var body: some View {
NavigationView {
VStack {
Text("This should dismiss the modal. But it just pops the NavigationView")
.padding()
Button(action: {
// This will set the showModal var back to false in all three views, and will dismiss the current sheet.
self.showModal.toggle()
}) {
Text("Finish")
}
.padding()
.foregroundColor(.white)
.background(Color.blue)
}
.navigationBarTitle("Page Two")
}
}
}
I found out you can actually make showModal into an EnvironmentObject, then simplify toggle the showModal to false on PageTwoContent to dismiss both PageOneContent and PageTwoContent.

iOS SwiftUI: pop or dismiss view programmatically

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")
})

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