NavigationLink onTapGesture and navigation not firing consistently - swiftui

In a SwiftUI view I implemented a vertically scrolling list by creating a VStack that contains a NavigationView that contains some text. I build this by looping through a popularFeedTypes object creating a NavigationLink for each item in the popularFeedTypes object. If a user clicks on the NavigationLink the user is pushed to a new view called FeedTypeView. You can see the code below.
VStack{
NavigationView{
List (self.popularFeedTypes.popularFeedTypes!, id: \.self) { feedType in
NavigationLink(destination: FeedTypeView(feedType: feedType)) {
Text(feedType.feedType)
}.onTapGesture {
print("TAPPED")
}
}
.navigationBarTitle(Text("Discover"), displayMode: .inline)
}
}
The problem I am experiencing is that if I have an onTapGesture action on the NavigationLink, I experience a different behavior from within the simulator depending upon how I click the row. If I click on the text or on the arrow (>) at the right hand side of the row, the onTapGesture fires off but no navigation occurs. If I click on the space between the text and the arrow, onTapGesture does not fire but navigation occurs. If I remove the onTapGesture code, clicking any of the three places causes navigation to occur. So my question is shouldn't navigation occur even with an onTapGesture action existing? Also shouldn't the onTapGesture action fire off regardless of where you click on the row that makes up the NavigationLink?

VStack {
NavigationView{
List (self.popularFeedTypes.popularFeedTypes!, id: \.self) { feedType in
NavigationLink(destination: FeedTypeView(feedType: feedType)) {
Text(feedType.feedType)
}
.simultaneousGesture(TapGesture().onEnded {
print("TAPPED")
})
.buttonStyle(PlainButtonStyle())
}
.navigationBarTitle(Text("Discover"), displayMode: .inline)
}
}
This should work. use simultaneousGesture on NavigationLink

You can use onAppear to handle tapped event.
VStack {
NavigationView {
List(self.popularFeedTypes.popularFeedTypes!, id: \.self) { feedType in
NavigationLink(
destination: FeedTypeView(feedType: feedType).onAppear { print("TAPPED") }) {
Text(feedType.feedType)
}
}
.navigationBarTitle(Text("Discover"), displayMode: .inline)
}
}

If you want to perform both action and navigation simultaneously you can do this:
VStack{
NavigationView{
List (self.popularFeedTypes.popularFeedTypes!, id: \.self) { feedType in
NavigationLink(destination: FeedTypeView(feedType: feedType)) {
Text(feedType.feedType)
}
.simultaneousGesture(TapGesture().onEnded{
print("TAPPED")
})
}
.navigationBarTitle(Text("Discover"), displayMode: .inline)
}
}

If you want to do something before your navigation link is triggered, you can initialize a navigation link with tag and selection.
struct someViewName: View {
#State var navigationLinkTriggerer: Bool? = nil
#State var navigationLinkFeedType: FeedType
var body: some View {
VStack {
NavigationLink(destination: FeedTypeView(feedType: navigationLinkFeedType),
tag: true,
selection: $navigationLinkTriggerer) {
EmptyView()
}
NavigationView {
List (self.popularFeedTypes.popularFeedTypes!, id: \.self) { feedType in
Button(feedType) {
// do all you want here
print("TAPPED")
// then set the navigationLinkTriggerer to value of you navigation link `tag`
// in this case tag is equal to `true`
// this will trigger the navigation link
self.navigationLinkFeedType = feedType
self.navigationLinkTriggerer = true
}
}
.navigationBarTitle(Text("Discover"), displayMode: .inline)
}
}
}
}

Related

Navigation Link Returning Back Two Levels on Exit

I am having trouble with a return from a navigation view within a tabbed view. My project has a Settings tab where the user may select via navigation link "View Entries". And from there another navigation link to "Add New Entry". Returning from Add New Entry should bring you to View Entries but instead is return another level to the Setting Menu.
I am seeing a warning on the console stating "trying to pop to a missing destination at /Library/Caches/com.apple...". Using the tabbed view sample code at SwiftUI NavigationView trying to pop to missing destination (Monoceros?) I no longer get the "pop-to-missing-destination" warning but I still have the same problem with the navigation return.
The sample code below is ready to run and test in Xcode 12.
In the sample code below, tap settings and select the navigation view "View Entries". This would be a screen where entries are displayed in a list. Tapping the plus button is where new entries could be added. The textfield on the "Add New Entry" screen doesn't do anything. Clicking the Save or Back buttons should return you to "View Entries" screen but instead returns you to the Setting Menu. The Save button uses presentationMode.wrappedValue.dismiss to dismiss the view.
The fact that two different version of the tab view logic didn't have any impact on my navigation view return logic leads me to believe that I just have some kind on plain old bug in my navigation view logic but I sure don't see one. The sample code below is using the standard tab view logic.
struct ContentView: View {
#State private var selection = 0
var body: some View {
NavigationView {
TabView (selection: $selection) {
HomeView()
.tabItem {
Label("Home", systemImage: "house")
}.tag(1)
AView()
.tabItem {
Label("A", systemImage: "a.circle")
}.tag(2)
BView()
.tabItem {
Label("B", systemImage: "b.circle")
}.tag(3)
SettingsView()
.tabItem {
Label("Settings", systemImage: "gearshape")
}.tag(4)
}
}
}
}
struct HomeView: View {
var body: some View {
Text("Home Screen")
}
}
struct AView: View {
var body: some View {
Text("A Screen")
}
}
struct BView: View {
var body: some View {
Text("B Screen")
}
}
struct SettingsView: View {
var body: some View {
VStack (alignment: .leading) {
List {
Text("Settings")
.font(.title)
.fontWeight(.bold)
.padding(.leading, 15)
NavigationLink(destination: SetAView()) {Text("View Entries")}
}
}
.font(.body)
}
}
struct SetAView: View {
var body: some View {
List {
Text("View Entries")
.padding(.vertical, 10)
Text("Normally entires would be displayed here")
Text("Should return here upon adding new entry")
.padding(.vertical, 10)
Text("Click the + button to add new entry")
}
.navigationBarItems(trailing: NavigationLink (destination: AddTestView()) {
Image(systemName: "plus")
.resizable()
.foregroundColor(Color(.systemBlue))
.frame(width: 18, height: 18)
} // body
)
}
}
struct AddTestView: View {
#Environment(\.presentationMode) var presentationMode
#State private var catSelect: String = ""
var body: some View {
NavigationView {
VStack {
Form {
Section {
TextField("Enter Entry Name", text: $catSelect)
.padding(.horizontal, 20)
.keyboardType(.default)
}
}
}
.navigationBarTitle(Text("Add new Entry"), displayMode: .inline)
.navigationViewStyle(StackNavigationViewStyle())
.navigationBarItems(trailing: Button(action: {
self.presentationMode.wrappedValue.dismiss()
}) {
Text ("Save")
})
}
}
}
After considerable analysis I discovered in my actual code that I had two copies of NavigationView––nothing wrong with the TabView code. Removing the one NavigationView not in contentView then caused several functions from working so rebuilt them from scratch. Now have everything working with TabView and NaigationView including the back buttons.

Customize navigationBar in Swift UI

I am new in swift ui. I want to put image button on the side of the NavigationBar title.
I want to be able to click the user image and navigate to another view. How?
You need to use navigationBarItems for putting image to navigation bar and you should add NavigationLink to that image. For center the title you need to set navigation bar title's displayMode to .inline or you can use new Toolbar api
struct ContentView: View {
var body: some View {
NavigationView {
Text("Welcome to Stack Overflow")
.navigationBarTitle("Header", displayMode: .inline)
.navigationBarItems(leading: NavigationLink(destination: Text("Destination")) {
Image(systemName: "person.crop.circle.fill")
.font(.title)
})
}
}
}
Screenshot
Another way using toolbar item.
I am adding TapGesture on image icon, and keeping it out of navigation link, as the image is not getting circular inside the NavigationLink in ToolbarItemGroup.
By leveraging isActive property of NavigationLink which monitors onTap state we can determine either we want to push our view or not.
import SwiftUI
struct WeatherView: View {
#State var onTap = false
var borderColor: Color = Color("Black")
var addProjectToolbarItem: some ToolbarContent {
ToolbarItemGroup(placement: .navigationBarLeading) {
NavigationLink(destination:Text("Welcome"), isActive: self.$onTap) {
EmptyView()
}
Image("yourImage")
.resizable()
.frame(width: 32, height: 32)
.clipShape(Circle())
.onTapGesture {
onTap.toggle()
}
}
}
var body: some View {
NavigationView {
VStack {
Text("First view")
}
.toolbar{
addProjectToolbarItem
}
.navigationTitle("Header")
.navigationBarTitleDisplayMode(.inline)
}
}
}

SwiftUI - TabView with nested NavigationViews resets Navigationflow

I'm having a TabView with Navigation Views in it.
struct ContentView: View {
var body: some View {
TabView {
NavigationView {
NavigationLink("Link to my first Navigation Level", destination: MyFirstView())
}
.tabItem {
Image(systemName: "house")
Text("Home")
}.tag(0)
NavigationView {
Text("Second Nav Page")
}
.tabItem {
Image(systemName: "gear")
Text("Settings")
}.tag(1)
}
}
}
struct MyFirstView: View {
#State var selectedTag: String?
var body: some View {
VStack {
Text("My First View")
NavigationLink("(Working) Link to my second Navigation Level", destination: MySecondView())
Text("But the Button in the Navigation Bar doesn't work")
}
.navigationBarTitle("My First View", displayMode: .inline)
.navigationBarItems(
leading: HStack {
NavigationLink(destination: MySecondView(), tag: "xx", selection: $selectedTag ){
Button(action: {
print("Settings button pressed...")
self.selectedTag = "xx"
}) {
Image(systemName: "gearshape.2.fill").imageScale(.large)
}
}
}
)
}
}
struct MySecondView: View {
var body: some View {
Text("My Second View")
}
}
Now I got a super weired behavior. If I click on "Link to my first Navigation Level" and then on "(Working) Link to my second Naviation Level" the journey works. If I click on "Back" while being in the second Navigation Level it goes back to the first Navigation Level.
Issue:
When I click on the gear symbol in the Navbar on the first Navigation Level it kind of escapes from the nested Navigation and sets it to the top level. This has the consequence that when I click on "Back" it brings me from the Second Navigation Level back to the very root screen but my expected behavior is that it should go back to the first Navigation Level.
Any ideas what I'm doing wrong? I'm using Xcode 12.2 beta 3 and iOS 14.2 (not sure if it's a beta bug).
Many Thanks!
This did the trick (thanks #Asperi). Has to be outside tabBarItems
NavigationLink(destination: AddDetailView(existingItem: nil),
isActive: $addMode) { EmptyView() }

SwiftUI ToolbarItem doesn't present a View from a NavigationLink

I don't know if this is a bug or I am doing something wrong here. I've added a new button on the Navigation bar that would present a new view.
struct MyView: View {
#ObservedObject var viewModel = MyViewModel()
var body: some View {
List(viewModel.data, id: \.name) { data in
NavigationLink(destination: MyDetailView(data: data.name)) {
Text(data.name)
}
}
.listStyle(InsetGroupedListStyle())
.edgesIgnoringSafeArea(.all)
.toolbar {
ToolbarItem(placement: .navigationBarTrailing) {
NavigationLink(destination: MyDetailView()) {
Text("New Element")
}
}
}
}
}
This is being tested on the newest iOS 14 beta (beta 6) and Xcode 12 (beta 6). As far as I know a Navigation Link presents fine the new view when on a List but in the toolbar as shown that's not the case. The button on the toolbar it's visible and active but doesn't trigger showing the new view.
I found using an HStack with an empty text as the first element also works, it lets the navigationLink act correctly.
.toolbar {
ToolbarItem(placement: .navigationBarLeading) {
HStack {
Text("")
NavigationLink(destination: SettingsView()) {
Image(systemName: "gear")
.font(.title)
}
}
}
NavigationLink should be inside NavigationView. Toolbar is not in NavigationView, put buttons in it.
So assuming you have somewhere in parent
NavigationView {
MyView()
}
here is a solution:
struct MyView: View {
#ObservedObject var viewModel = MyViewModel()
#State private var showNew = false
var body: some View {
List(viewModel.data, id: \.name) { data in
NavigationLink(destination: MyDetailView(data: data.name)) {
Text(data.name)
}
}
.listStyle(InsetGroupedListStyle())
.background(
NavigationLink(destination: MyDetailView(), isActive: $showNew) {
EmptyView()
}
)
.edgesIgnoringSafeArea(.all)
.toolbar {
ToolbarItem(placement: .navigationBarTrailing) {
Button("New Element") {
self.showNew = true
}
}
}
}
}
Using Asperi solution may not work if your navigation link directs to a view with keyboard input.
After navigation link, toolbar in the new view loaded correctly but when providing input with keyboard and dismissing keyboard all toolbar items disappears.
The solution is to place NavigationLink not in View but in navigationBarItems, example:
.navigationBarItems(
leading:
NavigationLink(
destination: Creator(),
isActive: $showCreator,
label: {
Text("")
}))

SwiftUI NavigationButton without the disclosure indicator?

When making a List with a row that pushes to a new view, SwiftUI adds a disclosure indicator ">" automatically? How do I remove it if I don't want it?
NavigationView {
List {
NavigationButton(destination: DetailView()) {
ListItem()
}
}
.navigationBarTitle(Text("Some title"))
}
On a UITableViewCell you set Accessory to None but how do I do that in SwiftUI?
Setting the NavigationLink width and hiding it did the trick for me
List {
ForEach(pages) { page in
HStack(spacing: 0) {
Text("Something")
NavigationLink(destination: Text("Somewhere")) {
EmptyView()
}
.frame(width: 0)
.opacity(0)
}
}
}
Swift 5, Xcode 11. ZStack works perfect.
var body: some View {
NavigationView {
List {
ForEach(viewModel.currenciesViewModel) { cellViewModel in
ZStack {
cellViewModel.makeView()
NavigationLink(destination: ChooseCurrencyListView()) {
EmptyView()
}
.buttonStyle(PlainButtonStyle())
}
}
}
.navigationBarHidden(true)
.navigationBarTitle("", displayMode: .inline)
}
}
The easiest one. The content for each item in the list.
ZStack {
NavigationLink(destination: DetailView()) {
EmptyView()
}.hidden()
RowView()
}
As workaround I can suggest to add .padding modifier like this:
NavigationView {
List {
NavigationButton(destination: DetailView()) {
ListItem()
}
}
.navigationBarTitle(Text("Some title"))
}
.padding(.trailing, -32.0)
So you will get rows without visible disclosure:
You can also put it in the .background modifier:
List {
Text("Go to...")
.background(NavigationLink("", destination: Text("Detail View")))
}
If you already have the background modifier on the Text, you can wrap the Text in a HStack and apply background to the HStack.
What you can do, if you are using list, is setting the navigationlink to hidden and its frame width to zero.
HStack{
Button(action: {self.statusShow = 1}, label: {
Image(systemName: "info.circle")
})
NavigationLink(destination: StimulatorSettingView(),
tag: 1,
selection: self.$statusShow){
EmptyView()
}.hidden().frame(width: 0)
}
This worked for me.
As of beta 6, this works well:
struct SwiftUIView: View {
var body: some View {
NavigationView {
List {
HStack {
Text("My Cell Content")
NavigationLink(destination: Text("destination"), label: {
EmptyView()
})
}
}
}
}
}
You don't have to use NavigationLink to wrap your Label directly. It will work as long as the link is anywhere in your view hierarchy.
Here I've wrapped it in a button, which allows you to trigger an action prior to pushing the view. Since the NavigationLink has an EmptyView for the label the disclosure indicator is not visible. You can also style this with ButtonStyle.
struct NavigationButton<Destination: View, Label: View>: View {
var action: () -> Void = { }
var destination: () -> Destination
var label: () -> Label
#State private var isActive: Bool = false
var body: some View {
Button(action: {
self.action()
self.isActive.toggle()
}) {
self.label()
.background(NavigationLink(destination: self.destination(), isActive: self.$isActive) {
EmptyView()
})
}
}
}
And to use it:
NavigationButton(
action: { print("tapped!") },
destination: { Text("Pushed View") },
label: { Text("Tap me") }
)
NavigationLink is what we should define in a scope enclosed inside a NavigationView.
But when we use NavigationLink it is attached to the enclosing view, so to reuse the same NavigationLink with other views, we use tag which differentiates between different Destinations.
struct SwiftUIView: View {
#State private var viewState: Int? = 0
var body: some View {
NavigationView {
VStack {
NavigationLink(destination: Text("View 1"), tag: 1, selection: $viewState) {
EmptyView()
}
NavigationLink(destination: Text("View 2"), tag: 2, selection: $viewState) {
EmptyView()
}
Text("First View")
.onTapGesture {
self.viewState = 1
}
Text("Second View")
.onTapGesture {
self.viewState = 2
}
}
}
}
}
Here we bind a Hashable property with all the NavigationLinks present in our VStack so that when a particular View is tapped we can notify which Destination should be opened by setting the value of Bindable property.
If we don't notify the correct Destination by setting the value of tag, always the View defined inside the Closure of NavigationLink will be clickable and nothing else.
Using this approach you don't need to wrap all your clickable views inside NavigationView, any action on any view can use any NavigationLink just by setting the tag.
Thanks, hope this helps.
Works well for me!
import SwiftUI
struct LandmarkList: View {
var body: some View {
NavigationView {
List(landmarkData) { landmark in
LandmarkRow(landmark: landmark)
NavigationLink(destination: LandmarkDetail(landmark: landmark)) {
EmptyView()
}
}
.navigationBarTitle(Text("Landmarks"))
}
}
}
struct LandmarkList_Previews: PreviewProvider {
static var previews: some View {
ForEach(["iPhone SE", "iPhone 11 Pro Max"], id: \.self) { deviceName in
LandmarkList()
.previewDevice(PreviewDevice(rawValue: deviceName))
.previewDisplayName(deviceName)
}
}
}
Use .frame(width: 0).opacity(0.0):
NavigationView {
List {
ForEach(options) {
option in
ZStack {
YourView(option: option)
NavigationLink(destination: ProductListView(),
label: {
EmptyView()
}).frame(width: 0).opacity(0.0)
}.listRowInsets(EdgeInsets())
}
}.navigationBarHidden(true)
}
My version of this solution is to make a view modifier. I think it's the cleanest way, as it doesn't use AnyView.
Note that this solution runs the init() for the destination when it draws the element the .navigationLink() is attached to.
Usage
Text("Link")
.navigationLink({
// put your destination here
})
How To
import SwiftUI
extension View {
func navigationLink<Destination: View>(_ destination: #escaping () -> Destination) -> some View {
modifier(NavigationLinkModifier(destination: destination))
}
}
fileprivate struct NavigationLinkModifier<Destination: View>: ViewModifier {
#ViewBuilder var destination: () -> Destination
func body(content: Content) -> some View {
content
.background(
NavigationLink(destination: self.destination) { EmptyView() }.opacity(0)
)
}
}
This helps to push and pass the model to the next navigation view controller.
struct ContentView : View {
#State var model = PostListViewModel()
var body: some View {
NavigationView {
List(model.post) { post in
ListCell(listData: post)
}.navigationBarTitle(Text("My Post"))
}
}
}
struct ListCell: View {
var listData: Post
var body: some View {
return NavigationButton(destination: DetailContentView(post: listData)) {
HStack {
ImageRow(model: listData) // Get image
VStack(alignment: .leading) {
Text(listData.login).font(.headline).lineLimit(nil)
Text(listData.url).font(.subheadline).lineLimit(nil)
}.padding(.leading, 10)
}.padding(.init(top: 5, leading: 0, bottom: 5, trailing: 0))
}
}
}
Here's a reusable "plain" navigation link view (i.e. without the chevron disclosure indicator) that can be a drop-in replacement for NavigationLink:
struct PlainNavigationLink<Label, Destination>: View where Label: View, Destination: View {
#ViewBuilder var destination: () -> Destination
#ViewBuilder var label: () -> Label
var body: some View {
label()
.background(
NavigationLink(destination: destination, label: {})
.opacity(0)
)
}
}
To use it, simply replace NavigationLink with PlainNavigationLink:
NavigationView { // or NavigationStack in iOS 16
List {
ForEach(1...30, id: \.self) { _ in
PlainNavigationLink {
Text("Hello, world!")
} label: {
Text("Hello, world!")
}
}
}
}
We can also extend it with convenience initializers for LocalizedStringKey and String, just like NavigationLink does.
just came here looking for the answer to this question, but none of the proposed solutions worked for me (can't have an empty view, because i want to put something in the list row; i'm already messing with the padding (and increasing trailing padding didn't seem to work) ... i was about to give up, and then something occurred to me: what if you crank up the z-index of the list row itself? seemed somewhat unlikely, but i gave it a try and, i'll be damned, it worked! i was so pleasantly surprised, i felt like sharing ...
e.g.:
// in body of your list row view
HStack(alignment: .top, spacing: 0.0) {
// stuff ...
}
.zIndex(9999999999)
If you need children behaviour for List and NavigationLink, without additional discloser in the same time, I want to promote this tricky solution, main point at HStack
var body: some View {
NavigationView {
List(items, children: \.items) { item in
ZStack {
NavigationLink(destination: DetailsView()) {
EmptyView()
}.hidden()
HStack {
RowView(item: item)
Spacer()
}
}
}
}
}
Once you put your button in a scrollview, the disclosure button will be hidden. Just make sure to disable your scroll indicator.
there is no documentation yet, so you can use ScrollView for now
NavigationView {
ScrollView {
ForEach(0...100){ x in
NavigationButton(destination: Text("ss")) {
HStack {
Text(String(x))
Spacer()
}
.padding()
.background(Color.white)
.shadow(radius:1,y:1)
}
}
.frame(width: UIScreen.main.bounds.width - 32)
.padding()
}
}
Removing List and just using ForEach works fine with navigation link. You just have to create your own list row. This works for me
NavigationView {
ForEach(pages) {
page in
NavigationLink(destination: DetailView()) {
ListItem()
}
}
}