How to create animation with delay when dismiss view swiftui - ios

I used the following example ( iOS SwiftUI: pop or dismiss view programmatically ) in my code, but I don't know how to create an animation just like flipping a page and put several seconds delay when [Button] tapped.Does anyone know a solution?
struct DetailView: View {
#Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>
var body: some View {
Button(
"Here is Detail View. Tap to go back.",
action: {
//withAnimation(.linear(duration: 5).delay(5))// Error occurred in dalay.(Type of expression is ambiguous without more context)
withAnimation(.linear(duration: 5)) // not work
{
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()
}
}
}

This would be one way to do it. Without the NavigationLink you have full control over all animations and transitions.
struct DetailView: View {
#Binding var showDetail:Bool
var body: some View {
Button(
"Here is Detail View. Tap to go back.",
action: {
withAnimation(Animation.linear.delay(2)){
self.showDetail = false
}
}
).frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity).background(Color.yellow)
}
}
struct RootView: View {
#State var showDetail = false
var body: some View {
VStack {
if showDetail{
DetailView(showDetail:self.$showDetail).transition(.move(edge: .trailing))
}else{
Button("I am Root. Tap for Detail View."){
withAnimation(.linear){
self.showDetail = true
}
}
}
}.frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity).background(Color.red)
}
}

You can dispatchQueue delay?
Button(
"Here is Detail View. Tap to go back.",
action: {
DispatchQueue.main.asyncAfter(deadline: .now() + 5.0) {
self.presentationMode.wrappedValue.dismiss()
}})

Related

Conditional component in SwiftUI

I'm giving my first steps with SwiftUI and I'm having problems with a component shown depending on a condition.
I'm trying to show a fullscreen popup (full screen with semi transparent black background and the popup in the middle with white background). To achieve this I've made this component:
struct CustomUiPopup: View {
var body: some View {
ZStack {
}
.overlay(CustomUiPopupOverlay, alignment: .top)
.zIndex(1)
}
private var CustomUiPopupOverlay: some View {
ZStack {
Spacer()
ZStack {
Text("POPUP")
.padding()
}
.zIndex(1)
.frame(width: UIScreen.main.bounds.size.width - 66)
.background(Color.white)
.cornerRadius(8)
Spacer()
}
.frame(width: UIScreen.main.bounds.size.width, height: UIScreen.main.bounds.size.height)
.background(Color.black.opacity(0.6))
}
}
If I set this in my main view, the popup is shown correctly over the button:
struct MainView: View {
var body: some View {
CustomUiPopup()
Button("Click to show popup") {
print("click on button")
}
}
}
If I set this, my popup is not shown (correct because hasToShowPopup is false), but if I click on the button it fails, the popup is not shown and the button can not be clicked again (?!), it seems like the view was freezed.
struct MainView: View {
#State private var hasToShowPopup = false
var body: some View {
if hasToShowPopup {
CustomUiPopup()
}
Button("Click to show popup") {
hasToShowPopup = true
}
}
}
I've even tried to initializate hasToShowPopup to true but the popup keeps failing, it's not shown in the first place:
struct MainView: View {
#State private var hasToShowPopup = true
var body: some View {
if hasToShowPopup {
CustomUiPopup()
}
Button("Click to show popup") {
hasToShowPopup = true
}
}
}
So my conclusion is that, I don't know why, but if I put my CustomUiPopup inside an "if" something is not rendered correctly.
What is wrong with my code?
Anyway, if this is not the correct approach to show a popup, I'll be glad to have any advice.
Following Ptit Xav suggestion I've tried this with the same results (my CustomUiPopup doesn't show):
struct MainView: View {
#State private var hasToShowPopup = false
var body: some View {
VStack {
if hasToShowPopup {
CustomUiPopup()
}
Button("Click to show popup") {
hasToShowPopup = true
}
}
}
}
This works fine with me:
struct CustomUiPopup: View {
var body: some View {
ZStack {
Spacer()
Text("POPUP")
.padding()
.zIndex(1)
.frame(width: UIScreen.main.bounds.size.width - 66)
.background(Color.white)
.cornerRadius(8)
Spacer()
}
.frame(maxWidth: .infinity, maxHeight: .infinity)
.background(
Color.black.opacity(0.6)
.ignoresSafeArea()
)
}
}
struct ContentView: View {
#State private var hasToShowPopup = false
var body: some View {
ZStack {
Button("Click to show popup") {
hasToShowPopup = true
}
if hasToShowPopup {
CustomUiPopup()
}
}
}
}

Can I use a button inside a SwiftUI sheet view that appears on top of my main SwiftUI view to change a subview inside the main view?

I'm trying to use a pop up menu (that appears when the user triggers it) to make the users of my app able to change the subview that is shown inside my main view between a Subview1 and a Subview2.
I'm trying to do that using global Bool variables that are changed when a button in the view inside the sheet is pressed. Based on those values, the main view should return a different subview
The problem is that when I try to select one option from the view that appears inside the sheet, the action of the Button is performed and the sheet is dismissed but the subview displayed by the main view remains unchanged
Is there a way to change the subview or reload the main view?
The code I'm using for the main view is:
struct ContentView: View {
#State var showMenu = false
var body: some View {
if(subview1Selected){
return AnyView(SubView1())
} else if (subview2Selected){
return AnyView(SubView2())
}
else {
return AnyView(
Button(action: {
showMenu = true
})
{
Text("Button")
}
.sheet(isPresented: $showMenu, content: {
MenuView()
})
)
}
}
the code I'm using for the pop-up sheet that is used like a menu is:
struct MenuView: View {
#Environment(\.presentationMode) var presentationMode
var body: some View {
List{
Button(action: {
subview1Selected = true
subview2Selected = false
self.presentationMode.wrappedValue.dismiss()
})
{
Text("Subview1")
}
Button(action: {
subview2Selected = true
subview1Selected = false
self.presentationMode.wrappedValue.dismiss()
})
{
Text("Subview2")
}
}
}
}
The subviews are:
struct SubView1: View {
#State var showMenu = false
var body: some View {
Button(action: {
showMenu = true
})
{
Text("SubView1")
}
.sheet(isPresented: $showMenu, content: {
MenuView()
})
}
}
and:
struct SubView2: View {
#State var showMenu = false
var body: some View {
Button(action: {
showMenu = true
})
{
Text("SubView2")
}
.sheet(isPresented: $showMenu, content: {
MenuView()
})
}
}
I think this is what you are trying to do. You can pass the #State showMenu variable as a #Binding variable into the menu. You can use a Bool if you only have 2 views, but it's more practical to use a custom enum, which I added for you. Also, the menu button should probably be separate from the subviews.
struct ContentView: View {
enum SubViewOption {
case subview1
case subview2
}
#State var showMenu = false
#State var subviewSelected: SubViewOption?
var body: some View {
ZStack() {
switch subviewSelected {
case .subview1:
SubView1()
case .subview2:
SubView2()
default:
Text("Select a view to begin.")
}
}
.frame(maxWidth: .infinity, maxHeight: .infinity)
.overlay(
Button(action: {
showMenu.toggle()
}, label: {
Text("Menu")
.padding()
.frame(maxWidth: .infinity)
.foregroundColor(.white)
.background(Color.gray.cornerRadius(30))
.padding()
})
, alignment: .bottom
)
.sheet(isPresented: $showMenu, content: {
MenuView(subviewSelected: $subviewSelected)
})
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
struct MenuView: View {
#Environment(\.presentationMode) var presentationMode
#Binding var subviewSelected: ContentView.SubViewOption?
var body: some View {
List {
Button(action: {
subviewSelected = .subview1
presentationMode.wrappedValue.dismiss()
}, label: {
Text("Subview1")
})
Button(action: {
subviewSelected = .subview2
presentationMode.wrappedValue.dismiss()
}, label: {
Text("Subview2")
})
}
}
}
struct SubView1: View {
var body: some View {
ZStack {
Color.red
.edgesIgnoringSafeArea(.all)
Text("THIS IS SUBVIEW 1")
.foregroundColor(.white)
}
}
}
struct SubView2: View {
var body: some View {
ZStack {
Color.blue
.edgesIgnoringSafeArea(.all)
Text("THIS IS SUBVIEW 2")
.foregroundColor(.white)
}
}
}

SwiftUI - NavigationBar in View from NavigationLink quickly showing then disappearing

I have a ContentView containing a NavigationView that leads to a DestinationView. I want to hide the navigation bar in the ContentView, but show it in the DestinationView. To hide it in the ContentView I set navigationBarHidden to true and give navigationBarTitle an empty string.
In the DestinationView I set navigationBarHidden to false and give it the title "DestinationView".
If I run the project and tap on the NavigationLink, the DestinationView shows the NavigationBar but quickly hides it after the view appeared. Can anybody help me with this?
struct ContentView: View {
var body: some View {
NavigationView {
ZStack {
Color.red.frame(maxWidth: .infinity, maxHeight: .infinity)
NavigationLink(destination: DestinationView()) {
ZStack {
Color.green.frame(width: 200, height: 200)
Text("Tap me")
}
}
}
.navigationBarTitle("")
.navigationBarHidden(true)
}
}
}
struct DestinationView: View {
var body: some View {
List {
Text("1")
Text("2")
}
.navigationBarTitle("DestinationView")
.navigationBarHidden(false)
}
}
You need to use variable to achieve this and bind it with your destination
struct ContentView: View {
#State var isNavigationBarHidden: Bool = true
var body: some View {
NavigationView {
ZStack {
Color.red.frame(maxWidth: .infinity, maxHeight: .infinity)
NavigationLink(destination: DestinationView(isNavigationBarHidden: self.$isNavigationBarHidden)) {
ZStack {
Color.green.frame(width: 200, height: 200)
Text("Tap me")
}
}
}
.navigationBarHidden(self.isNavigationBarHidden)
.navigationBarTitle("")
.onAppear {
self.isNavigationBarHidden = true
}
}
}
}
struct DestinationView: View {
#Binding var isNavigationBarHidden: Bool
var body: some View {
List {
Text("1")
Text("2")
}
.navigationBarTitle("DestinationView")
.onAppear {
self.isNavigationBarHidden = false
}
}
}
There is an issue with the safe area layout guide
struct ContentView: View {
var body: some View {
NavigationView {
ZStack {
Color.red.frame(maxWidth: .infinity, maxHeight: .infinity)
VStack {
NavigationLink(destination: DestinationView()) {
ZStack {
Color.green.frame(width: 200, height: 200)
Text("Tap me")
}
}
}
}.edgesIgnoringSafeArea(.all)
.navigationBarHidden(true)
}
}
}
struct DestinationView: View {
var body: some View {
VStack {
List {
Text("1")
Text("2")
}
}.navigationBarTitle("DestinationView")
.navigationBarHidden(false)
}
}
Happy Coding...
Edit: use the accepted answer as it's a much cleaner solution.
I encountered this bug and ended up using UIViewControllerRepresentable to wrap a controller which sets the navigation bar hidden state in its viewDidAppear method:
struct ContentView: View {
var body: some View {
NavigationView {
ZStack {
Color.red.frame(maxWidth: .infinity, maxHeight: .infinity)
NavigationLink(destination: DestinationView()) {
ZStack {
Color.green.frame(width: 200, height: 200)
Text("Tap me")
}
}
}
.navigationBarTitle("")
.navigationBarHidden(true)
}
}
}
struct DestinationView: View {
var body: some View {
List {
Text("1")
Text("2")
}
.navigationBarTitle("DestinationView")
.navigationBarHidden(false)
.background(HorribleHack())
}
}
struct HorribleHack: UIViewControllerRepresentable {
func makeUIViewController(context: Context) -> HorribleHackViewController {
HorribleHackViewController()
}
func updateUIViewController(_ uiViewController: HorribleHackViewController, context: Context) {
}
}
class HorribleHackViewController: UIViewController {
override func viewDidAppear(_ animated: Bool) {
DispatchQueue.main.async {
self.navigationController?.setNavigationBarHidden(false, animated: false)
}
}
}
For me passing a binding around through the view hierarchy wasn't optimal, adding the state to an environment var was preferable.
class SceneState: ObservableObject {
#Published var isNavigationBarHidden = true
}
class SceneDelegate: UIResponder, UIWindowSceneDelegate {
...
var sceneState = SceneState()
...
let contentView = ContentView().environmentObject(sceneState)
...
}
struct ContentView: View {
var body: some View {
NavigationView {
View1()
}
}
}
struct View1: View {
#EnvironmentObject var sceneState: SceneState
#State private var showView2: Bool = false
var body: some View {
VStack {
Text("NO nav bar.")
Button("Go to View2") {
self.showView2 = true
}
NavigationLink(destination: View2(), isActive: $showView2, label: {EmptyView()})
}
.navigationBarHidden(self.sceneState.isNavigationBarHidden)
.navigationBarTitle("")
.navigationBarBackButtonHidden(self.sceneState.isNavigationBarHidden)
}
}
struct View2: View {
#EnvironmentObject var sceneState: SceneState
var body: some View {
VStack {
Text("WITH nav bar.")
}
.navigationBarHidden(self.sceneState.isNavigationBarHidden)
.navigationBarTitle("WWDC")
.navigationBarBackButtonHidden(self.sceneState.isNavigationBarHidden)
.onAppear {
self.sceneState.isNavigationBarHidden = false
}
}
}
There ist actually a really simple solution to this problem. After many tries I figured it, that you have to add the .navigationBarHidden(false) directly to the destination view inside the NavigationLink like this:
struct ContentView: View {
var body: some View {
NavigationView {
ZStack {
Color.red.frame(maxWidth: .infinity, maxHeight: .infinity)
NavigationLink(destination: DestinationView()
.navigationBarHidden(false)) {
ZStack {
Color.green.frame(width: 200, height: 200)
Text("Tap me")
}
}
}
.navigationBarTitle("")
.navigationBarHidden(true)
}
}
}
struct DestinationView: View {
var body: some View {
List {
Text("1")
Text("2")
}
.navigationBarTitle("DestinationView")
.navigationBarHidden(false)
}
}
It will work like desired, and won't disappear after showing up.
I run this code on an iOS 14 Simulator and the navigation bar did not hide, so I assume this might be an issue with iOS 13. I had a similar problem and my code which resulted in nav bar disappearing on iOS 13.5 Simulator worked fine on iOS 14.4 Simulator.

Present a new view in SwiftUI

I want to click a button and then present a new view like present modally in UIKit
I have already seen "How to present a new view using sheets", but I don't want to attach it to the main view as a modal sheet.
And I don't want to use NavigationLink, because I don't want a new view and old view have a navigation relationship.
Thanks for your help...
To show a modal (iOS 13 style)
You just need a simple sheet with the ability to dismiss itself:
struct ModalView: View {
#Binding var presentedAsModal: Bool
var body: some View {
Button("dismiss") { self.presentedAsModal = false }
}
}
And present it like:
struct ContentView: View {
#State var presentingModal = false
var body: some View {
Button("Present") { self.presentingModal = true }
.sheet(isPresented: $presentingModal) { ModalView(presentedAsModal: self.$presentingModal) }
}
}
Note that I passed the presentingModal to the modal so you can dismiss it from the modal itself, but you can get rid of it.
To make it REALLY present fullscreen (Not just visually)
You need to access to the ViewController. So you need some helper containers and environment stuff:
struct ViewControllerHolder {
weak var value: UIViewController?
}
struct ViewControllerKey: EnvironmentKey {
static var defaultValue: ViewControllerHolder {
return ViewControllerHolder(value: UIApplication.shared.windows.first?.rootViewController)
}
}
extension EnvironmentValues {
var viewController: UIViewController? {
get { return self[ViewControllerKey.self].value }
set { self[ViewControllerKey.self].value = newValue }
}
}
Then you should use implement this extension:
extension UIViewController {
func present<Content: View>(style: UIModalPresentationStyle = .automatic, #ViewBuilder builder: () -> Content) {
let toPresent = UIHostingController(rootView: AnyView(EmptyView()))
toPresent.modalPresentationStyle = style
toPresent.rootView = AnyView(
builder()
.environment(\.viewController, toPresent)
)
NotificationCenter.default.addObserver(forName: Notification.Name(rawValue: "dismissModal"), object: nil, queue: nil) { [weak toPresent] _ in
toPresent?.dismiss(animated: true, completion: nil)
}
self.present(toPresent, animated: true, completion: nil)
}
}
Finally
you can make it fullscreen like:
struct ContentView: View {
#Environment(\.viewController) private var viewControllerHolder: UIViewController?
var body: some View {
Button("Login") {
self.viewControllerHolder?.present(style: .fullScreen) {
Text("Main") // Or any other view you like
// uncomment and add the below button for dismissing the modal
// Button("Cancel") {
// NotificationCenter.default.post(name: Notification.Name(rawValue: "dismissModal"), object: nil)
// }
}
}
}
}
For iOS 14 and Xcode 12:
struct ContentView: View {
#State private var isPresented = false
var body: some View {
Button("Show Modal with full screen") {
self.isPresented.toggle()
}
.fullScreenCover(isPresented: $isPresented, content: FullScreenModalView.init)
}
}
struct FullScreenModalView: View {
#Environment(\.presentationMode) var presentationMode
var body: some View {
VStack {
Text("This is a modal view")
}
.frame(maxWidth: .infinity, maxHeight: .infinity)
.background(Color.red)
.edgesIgnoringSafeArea(.all)
.onTapGesture {
presentationMode.wrappedValue.dismiss()
}
}
}
See also: How to present a full screen modal view using fullScreenCover()
Disclaimer: Below is not really like a "native modal", neither behave nor look&feel, but if anyone would need a custom transition of one view over other, making active only top one, the following approach might be helpful.
So, if you expect something like the following
Here is a simple code for demo the approach (of corse animation & transition parameters can be changed by wish)
struct ModalView : View {
#Binding var activeModal: Bool
var body : some View {
VStack {
Button(action: {
withAnimation(.easeInOut(duration: 0.3)) {
self.activeModal = false
}
}) {
Text("Hide modal")
}
Text("Modal View")
}
.frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity, alignment: .center)
.background(Color.green)
}
}
struct MainView : View {
#Binding var activeModal: Bool
var body : some View {
VStack {
Button(action: {
withAnimation(.easeInOut(duration: 0.3)) {
self.activeModal = true
}
}) {
Text("Show modal")
}
Text("Main View")
}
.frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity, alignment: .center)
.background(Color.yellow)
}
}
struct ModalContainer: View {
#State var showingModal = false
var body: some View {
ZStack {
MainView(activeModal: $showingModal)
.allowsHitTesting(!showingModal)
.disabled(showingModal)
if showingModal {
ModalView(activeModal: $showingModal)
.transition(.move(edge: .bottom))
.zIndex(1)
}
}
}
}
Here is a simple one way - forward views. It's very straight forward.
struct ChildView: View{
private let colors: [Color] = [.red, .yellow,.green,.white]
#Binding var index : Int
var body: some View {
let next = (self.index+1) % MyContainer.totalChildren
return ZStack{
colors[self.index % colors.count]
Button("myNextView \(next) ", action: {
withAnimation{
self.index = next
}
}
)}.transition(.asymmetric(insertion: .move(edge: .trailing) , removal: .move(edge: .leading) ))
}
}
struct MyContainer: View {
static var totalChildren = 10
#State private var value: Int = 0
var body: some View {
HStack{
ForEach(0..<(Self.totalChildren) ) { index in
Group{
if index == self.value {
ChildView(index: self.$value)
}}
}
}
}
}
then presents it from ContentView when a button is tapped:
struct SheetView: View {
#Environment(\.dismiss) var dismiss
var body: some View {
Button("Press to dismiss") {
dismiss()
}
.font(.title)
.padding()
.background(Color.black)
}
}
struct ContentView: View {
#State private var showingSheet = false
var body: some View {
Button("Show Sheet") {
showingSheet.toggle()
}
.sheet(isPresented: $showingSheet) {
SheetView()
}
}
}

SwiftUI How to push to next screen when tapping on Button

I can navigate to next screen by using NavigationButton (push) or present with PresentationButton (present) but i want to push when i tap on Buttton()
Button(action: {
// move to next screen
}) {
Text("See More")
}
is there a way to do it?
You can do using NavigationLink
Note: Please try in real device. in simulator sometimes not work properly.
struct MasterView: View {
#State var selection: Int? = nil
var body: some View {
NavigationView {
VStack {
NavigationLink(destination: DetailsView(), tag: 1, selection: $selection) {
Button("Press me") {
self.selection = 1
}
}
}
}
}
}
struct DetailsView: View {
#Environment(\.presentationMode) var presentation
var body: some View {
Group {
Button("Go Back") {
self.presentation.wrappedValue.dismiss()
}
}
}
}
As you can see to display the new view, add the NavigationLink with isActive: $pushView using <.hidden()> to hide the navigation "arrow".
Next add Text("See More") with tapGesture to make the text respond to taps. The variable pushView will change (false => true) when you click "See More" text.
import SwiftUI
struct ContentView: View {
#State var pushView = false
var body: some View {
NavigationView {
List {
HStack{
Text("test")
Spacer()
NavigationLink(destination: NewView(), isActive: $pushView) {
Text("")
}.hidden()
.navigationBarTitle(self.pushView ? "New view" : "default view")
Text("See More")
.padding(.trailing)
.foregroundColor(Color.blue)
.onTapGesture {
self.pushView.toggle()
}
}
}
}
}
}
struct NewView: View {
var body: some View {
Text("New View")
}
}
ContentView picture
NewView picture
To tap on button and navigate to next screen,You can use NavigationLink like below
NavigationView{
NavigationLink(destination: SecondView()) {
Text("Login")
.padding(.all, 5)
.frame(minWidth: 0, maxWidth: .infinity,maxHeight: 45, alignment: .center)
.foregroundColor(Color.white)
}
}
You can use NavigationLink to implement this:
struct DetailsView: View {
var body: some View {
VStack {
Text("Hello world")
}
}
}
struct ContentView: View {
#State var selection: Int? = nil
var body: some View {
NavigationView {
VStack {
NavigationLink(destination: DetailsView(), tag: 1, selection: $selection) {
Button("Press me") {
self.selection = 1
}
}
}
}
}
}

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