I have a watchOS App which uses the following layout:
NavigationView {
if !HKHealthStore.isHealthDataAvailable() {
ContentNeedHealthKitView()
} else if !isAuthorized {
ContentUnauthorizedView()
} else {
TabView(selection: $selection) {
WeightView()
.navigationTitle("Weight")
.tag(1)
.onAppear {
print("Appear!")
}
.onDisappear {
print("Disappear!")
}
SettingsView()
.navigationTitle("Settings")
.tag(2)
}
}
}
Unfortunately, the OnAppear and OnDisappear actions are only executed after transitioning from on view to another the second time. When swiping right the first time, nothing happens.
You should provide a minimal reproducible example (see https://stackoverflow.com/help/minimal-reproducible-example).
Also your lines are producing compiler errors. The correct way to use onAppear is like this:
.onAppear {
}
Here is a working example, everything is working as expected. You should also place the onAppear ViewModifier to the child view.
import SwiftUI
struct WeightView: View {
var body: some View {
Text("WeightView")
.onAppear {
print("Appear!")
}
.onDisappear {
print("Disappear!")
}
}
}
struct SettingsView: View {
var body: some View {
Text("SettingsView")
}
}
struct ContentView: View {
#State var selection = 1
#State var isAuthorized = false
var body: some View {
NavigationView {
if !isAuthorized {
Button("authorize") {
isAuthorized.toggle()
}
} else {
TabView(selection: $selection) {
WeightView()
.navigationTitle("Weight")
.tag(1)
SettingsView()
.navigationTitle("Settings")
.tag(2)
}
}
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
Related
I have 3 windows that are connected by a NavigationLink and the NavigationBar is hidden, but I need the ability to swipe to go back, for this I use this code:
import SwiftUI
extension UINavigationController: UIGestureRecognizerDelegate {
override open func viewDidLoad() {
super.viewDidLoad()
interactivePopGestureRecognizer?.delegate = self
}
public func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool {
return viewControllers.count > 1
}
}
#main
struct testSheetApp: App {
var body: some Scene {
WindowGroup {
ContentView()
}
}
}
struct ContentView: View {
var body: some View {
NavigationView{
ZStack{
VStack{
NavigationLink(destination: {
ContentView2()
}, label: {
Text("new")
})
}
} .navigationBarHidden(true)
}
}
}
struct ContentView2: View {
#Environment(\.presentationMode) var presentationMode
var body: some View {
ZStack{
VStack{
Button(action: {
presentationMode.wrappedValue.dismiss()
}, label: {
Text("back")
})
NavigationLink(destination: {
ContentView3()
}, label: {
Text("next")
})
}
} .navigationBarHidden(true)
}
}
struct ContentView3: View {
#Environment(\.presentationMode) var presentationMode
var body: some View {
VStack{
Button(action: {
presentationMode.wrappedValue.dismiss()
}, label: {
Text("back")
})
}
.navigationBarHidden(true)
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
Everything works fine with the second form, you can return with a swipe, but on the 3rd form, when you cancel the swipe, when the screen remains on the same form, a NavigationBar appears
Bug NavigationBar
I found a solution to this problem, you need to add to the NavigationLink, ".isDetailLink (false)"
code snippet:
NavigationLink(destination: {
ContentView3()
}, label: {
Text("next")
}).isDetailLink(false)
to make it short: I want to have the same view of the list like in the first image i shared. But when I add a navigation bar item the list looks strange to me. It this a bug of the new version of Swift/XCode or needs something to be changed?
Code:
import SwiftUI
import CoreData
struct ContentView: View {
var body: some View {
NavigationView {
List{
Text("test1")
Text("test2")
Text("test3")
}
.navigationTitle("Test")
// .navigationBarItems(leading:
// Text("Test")
// )
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
Try using .navigationViewStyle as below:
struct ContentView: View {
#State private var isFullScreen = false
var body: some View {
NavigationView {
List{
Text("One")
Text("Two")
}
.navigationTitle("Testt")
.navigationBarItems(leading: Text("Add"))
}
.navigationViewStyle(StackNavigationViewStyle())
}
}
Hey! Give This A Try!
var body: some View {
NavigationView {
List{
Text("One")
Text("Two")
}
.navigationTitle("Testt, displayMode: .inline)
.navigationBarItems(leading: Text("Add"))
}
}
}
I have lately been trying to make a tvOS app, but have run into the following rather annoying problem. I can't use navigation inside a TabView and still have the menu button on the remove take me back to the previous state.
struct TestView: View {
#State var selection : Int = 0
var body: some View {
TabView(selection: self.$selection) {
ExpView()
.tabItem {
HStack {
Image(systemName: "magnifyingglass")
Text("Explore")
}
}
.tag(0)
}
}
}
struct ExpView: View {
var body: some View {
NavigationView {
NavigationLink(destination: DetailView(title: "Hey")) {
Text("Detail")
}
}
}
}
struct DetailView: View {
var title : String
var body: some View {
VStack {
Text(title)
}
}
}
My question is: Is there any way to enable the menu button to go back to the previous view in the hierachy without dismissing the app completely?
You don't need to call dismiss on Menu it is called automatically for NavigationLink (so calling one more dismiss quits to main menu)
Here are fixed views. Tested with Xcode 11.4
struct ExploreView: View {
var body: some View {
NavigationView {
NavigationLink(destination: DetailView(title: "Hey")) {
Text("Detail")
}
}
}
}
struct DetailView: View {
var title : String
var body: some View {
VStack {
Text(title)
}
}
}
So I found a workaround for the issue.
If you place the navigationView outside the TabView and then use the following code it works:
struct TestView: View {
#State var selection : Int = 0
#State var hideNavigationBar : Bool
var body: some View {
NavigationView {
TabView(selection: self.$selection) {
ExpView(hideNavigationBar: self.$hideNavigationBar)
.tabItem {
HStack {
Image(systemName: "magnifyingglass")
Text("Explore")
}
}
.tag(0)
}
}
}
}
struct ExpView: View {
#Binding var hideNavigationBar : Bool
var body: some View {
NavigationLink(destination: DetailView(title: "Hey")) {
Text("Detail")
}.navigationBarTitle("")
.navigationBarHidden(self.hideNavigationBar)
.onAppear {
self.hideNavigationBar = true
}
}
}
struct DetailView: View {
var title : String
var body: some View {
VStack {
Text(title)
}
}
}
Consider the following code:
class ApplicationHostingView: ObservableObject {
#Published var value: Bool
}
struct ApplicationHostingView: View {
// view model env obj
var body: some View {
Group {
if applicationHostingViewModel.value {
LoginView()
.transition(.move(edge: .leading)) // <<<< Transition for Login View
} else {
IntroView()
}
}
}
}
struct IntroView: View {
// view model env obj
var body: some View {
Button(action: { applicationHostingViewModel.value = true }) {
Text("Continue")
}
}
}
struct LoginView: View {
var body: some View {
Text("Hello World")
}
}
ISSUE
In this case, I see my transition from IntroView to LoginView work fine except for any of the animations. Animations inside IntroView based on the conditionals seem to be working fine but transitions that change the entire screen don't seem to work.
change group to ZStack
add animation somewhere.
class ApplicationHostingViewModel: ObservableObject {
#Published var value: Bool = false
}
struct ApplicationHostingView: View {
// view model env obj
#ObservedObject var applicationHostingViewModel : ApplicationHostingViewModel
var body: some View {
ZStack {
if applicationHostingViewModel.value {
LoginView()
.transition(.move(edge: .leading))
} else {
IntroView(applicationHostingViewModel:applicationHostingViewModel)
}
}
}
}
struct IntroView: View {
// view model env obj
#ObservedObject var applicationHostingViewModel : ApplicationHostingViewModel
var body: some View {
Button(action: {
withAnimation(.default){
self.applicationHostingViewModel.value = true} }) {
Text("Continue")
}
}
}
struct LoginView: View {
var body: some View {
Text("Hello World").frame(maxWidth: .infinity, maxHeight: .infinity)
}
}
Im trying to link a button action in SomeView1() to navigate to a someView2() without having the back button at the top of the screen. Instead, I want to add another button in SomeView2() that will navigate back to SomeView1(). is this possible in SwiftUI yet?
SomeView1()
struct SomeView1: View {
var body: some View {
NavigationView {
VStack {
//...view's content
NavigationLink(destination: SomeView2()) {
Text("go to SomeView2")
}
Spacer()
}
}
}
}
SomeView2()
struct SomeView2: View {
var body: some View {
NavigationView {
VStack {
//...view's content
NavigationLink(destination: SomeView1()) {
Text("go to SomeView1")
}
Spacer()
}
}
}
}
this is what it looks like:
The right way to get what you want here is to use the presentationMode environment variable:
import SwiftUI
struct View2: View {
#Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>
var body: some View {
VStack {
Button(action: {
self.presentationMode.wrappedValue.dismiss()
}) {
Text("POP")
}
}
.navigationBarTitle("")
.navigationBarBackButtonHidden(true)
.navigationBarHidden(true)
}
}
struct ContentView: View {
var body: some View {
NavigationView {
NavigationLink(destination: View2()) {
Text("PUSH")
.navigationBarTitle("")
.navigationBarHidden(true)
}
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
You can do something like this in SomeView2():
NavigationView {
VStack {
//...view's content
NavigationLink(destination: SomeView1()) {
Text("go to SomeView1")
}
Spacer()
}
}.navigationBarBackButtonHidden(true)
I believe that you should use only one NavigationView for the whole navigation process. Now you have three NavigationViews inside each other, which produces three back buttons.
So in your case it would become something like this:
struct SomeView1InsideNavigationView: View { // This should be the first view you present
var body: some View {
NavigationView { // Use NavigationView only once
SomeView1()
}
}
}
struct SomeView1: View {
var body: some View {
VStack { // Do *not* use NavigationView here
//...view's content
NavigationLink(destination: SomeView2()) {
Text("go to SomeView2")
}
Spacer()
}
}
}
struct SomeView2: View {
var body: some View {
VStack { // Do *not* use NavigationView here
//...view's content
NavigationLink(destination: SomeView1()) {
Text("go to SomeView1")
}
Spacer()
}
}
}