SwiftUI NavigationLink still broken in Xcode 11.4 simulators? - ios

I'm aware of the bug that was supposedly recently fixed in Xcode 11.4, where if you ran a simulator with iOS 13, the back button for a navigation link wouldn't function correctly. I checked that I'm on 11.4, with the following terminal output,
myUser#myUser ~ % /usr/bin/xcodebuild -version
Xcode 11.4
Build version 11E146
and yet I'm still having trouble with the back button from NavigationLink. I don't have access to a real device to test on, but either way this issue was said to have been fixed. Am I setting up the NavigationLink incorrectly?
Here's example code of my setup:
//in primary view
NavigationLink(destination: Test()) {
Text("Hit Me!")
.fontWeight(.semibold)
.font(.title)
.padding()
.foregroundColor(.white)
.background(LinearGradient(gradient: Gradient(colors: [Color(.white),Color(.blue)]), startPoint: .leading, endPoint: .trailing))
.cornerRadius(40)
}
//the view being navigated to
//I can make it to this page but cannot navigate back
struct Test : View {
var body: some View {
Text("Hi!")
}
}

I'm answering my own question in case someone else makes the same small mistake as myself: NavigationView must be the outer most view in your body. I initially had
KeyboardHost { //Custom view class
NavigationView {
VStack {
....
Switching to the following fixed the issue
NavigationView {
KeyboardHost {
VStack {

Related

SwiftUI NavigationView content only visible in iPad sidebar

My app is working as expected across all iPhone models, but when running on iPad I notice that the my application content, which is wrapped within a NavigationView, only displays in the iPad's sidebar, and only after tapping the 'Back` toolbar button.
var body: some View {
NavigationView{
ZStack{
...
}
.navigationBarTitleDisplayMode(.inline)
.toolbar {
ToolbarItem(placement: .principal) {
VStack {
Text("Add Light to Your Journey")
.font(Font.custom("EduTASBeginner-Regular", size: 24))
...
}
}
I found a similar question on SO that suggested adding the attribute .navigationViewStyle(.stack), but this did not change the way the app is displayed on iPad:
Note the solution on this similar post also did not resolve the issue.
As noted in the comments on the linked post, the .navigationViewStyle(StackNavigationViewStyle()) must be applied directly to the NavigationView, and not a view contained therein as with .navigationTitle

Keyboard safe area wrong for iPad in multitasking Slide Over (SwiftUI/UIKit)

I've got a view with content on the bottom edge, which gets partially obscured by the keyboard when the app is in Slide Over. This isn't the case in side-by-side multitasking or when the app is full screen.
All other configurations are fine:
Side-by-side, with keyboard:
Slide over, without keyboard:
Here's the example view code:
struct ContentView: View {
#State private var text = ""
var body: some View {
VStack {
TextField("", text: $text)
.textFieldStyle(RoundedBorderTextFieldStyle())
Spacer()
Text("Hello, world!")
.font(.title)
}
}
}
I've noticed this issue in SwiftUI lifecycle apps, UIKit lifecycle apps, across different iOS versions (including iOS 14) and on all iPad sizes.
I've seen solutions that check the UIDevice.current.userInterfaceIdiom and the window bounds to check if the app is in Slide Over and adjust the UI, but I'm using SwiftUI and I'd like to avoid this kind of hack. Any advice on how to deal with this?

SwiftUI - unexpected behaviour using onTapGesture with mouse/trackpad on iPadOS and Catalyst

I have in my app a layout showing a list of rectangular cards - each one should be tappable (once) to reveal a set of action buttons and more information, etc.
I have implemented this using .onTapGesture() and I have also put .contentShape(Rectangle() to enforce the tappable area. However, while my implementation works fine for touchscreen interface, when I'm using it with the iPadOS mouse support, and on Catalyst for that matter, I see some very unexpected behaviour.
I've made a minimal reproducible example below that you can copy to recreate the problem.
Where the problems are when using mouse/trackpad input:
Not every click of the mouse is recorded as a tap gesture. This is happening mostly arbitrary except from in a few cases:
It seems to click either only in very specific areas, or when clicking multiple times in the same spot.
It seems that in a lot of cases only every other click is recorded. So I double click to get only one tap gesture.
It isn't evident in this example code, but in my main app the tappable areas are seemingly arbitrary - you can usually click near text or in alignment with it to record a tap gesture, but not always.
If you are running the example code you should be able to see the problem by repeatedly moving the mouse and attempting one click. It doesn't work unless you click multiple times in the same spot.
What does work as expected:
All input using touch instead of mouse; regardless of where you tap it records a tap gesture.
Mouse input when running as a native Mac target. The issues mentioned above are only for mouse/trackpad when running the example under iPadOS and Mac Catalyst.
Code I used to recreate this problem (has a counter to count every time a tap gesture is recorded):
struct WidgetCompactTaskItemView: View {
let title: String
let description: String
var body: some View {
HStack {
Rectangle()
.fill(Color.purple)
.frame(maxWidth: 14, maxHeight: .infinity)
VStack(alignment: .leading) {
Text(title).font(.system(size: 14, weight: .bold, design: .rounded))
Text(description).font(.system(.footnote, design: .rounded))
.frame(maxHeight: .infinity)
.fixedSize(horizontal: false, vertical: true)
.lineLimit(1)
.padding(.vertical, 0.1)
Spacer()
}
.padding(.horizontal, 6)
.padding(.top, 12)
}
.frame(maxWidth: .infinity, maxHeight: 100, alignment: .leading)
.background(Color.black)
.cornerRadius(16)
.overlay(
RoundedRectangle(cornerRadius: 16)
.stroke(Color.green, lineWidth: 0.5)
)
}
}
struct ContentView: View {
#State var tapCounter = 0
var body: some View {
VStack {
Text("Button tapped \(tapCounter) times.")
WidgetCompactTaskItemView(title: "Example", description: "Description")
.contentShape(Rectangle())
.onTapGesture(count: 1) {
tapCounter += 1
}
Spacer()
}
}
}
I have tried several things including moving modifiers around, setting eoFill to true on the contentShape modifier (which didn't fix the problem but simply made different unexpected behaviour).
Any help to find a solution that works as expected and works consistently whether mouse or touch would be much appreciated. I am not sure if I am doing something wrong or if there is a bug here, so please try and recreate this example yourself using the code to see if you can reproduce the problem.
So I realised that there was a much better solution that could bypass all the oddities that .onTapGesture had for me with mouse input. It was to encapsulate the whole view in a Button instead.
I made this into a modifier similar to onTapGesture so that it's much more practical.
import Foundation
import SwiftUI
public struct UltraPlainButtonStyle: ButtonStyle {
public func makeBody(configuration: Self.Configuration) -> some View {
configuration.label
}
}
struct Tappable: ViewModifier {
let action: () -> ()
func body(content: Content) -> some View {
Button(action: self.action) {
content
}
.buttonStyle(UltraPlainButtonStyle())
}
}
extension View {
func tappable(do action: #escaping () -> ()) -> some View {
self.modifier(Tappable(action: action))
}
}
Going through this:
I first have a button style which simply returns the label as is. This is necessary because the default PlainButtonStyle() still has a visible effect when clicked.
I then create a modifier that encapsulates the content given in a Button with this button style, then add that as an extension to View.
Usage example
WidgetCompactTaskItemView(title: "Example", description: "Description")
.tappable {
tapCounter += 1
}
This has solved all problems I've been having with clickable area using a mouse.

SwiftUI modal sheet dismisses itself after half a second

I have got a modal sheet, here is the code:
SettingsDashboardView:
#State private var notificationsSettingsSheet = false
var body: some View {
Button(action: {
self.notificationsSettingsSheet.toggle()
}) {
VStack(alignment: .leading) {
HStack(alignment: .top, spacing: 4) {
Label("Set Daily Reminders", systemImage: "alarm").foregroundColor(Color("TextColor"))
.font(.system(.headline, design: .rounded))
Spacer()
}
}
}
.sheet(isPresented: $notificationsSettingsSheet) {
NotificationSettingsModal()
}
}
NotificationSettingsModal:
var body: some View {
ZStack(alignment: .bottom) {
ScrollView {
VStack(alignment: .leading, spacing: 0) {
Text("Daily Reminders")
.font(.system(.title, design: .rounded))
.fontWeight(.bold)
.padding(.top, headingTopPadding)
.padding(.horizontal, headingHorizontalPadding).foregroundColor(Color("TextColor"))
Spacer().frame(height: 164)
}.frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity)
Spacer().frame(height: 64)
}
}.background(Color("BackgroundColor").edgesIgnoringSafeArea(.all))
}
When I launch the app and open my sheet, in about 50% of cases sheet dismisses itself after about half a second. If I open sheet after that everything works fine. What can cause this problem?
This will probably not solve the mentioned issue but can be useful for others.
In most cases, this issue happens when the view gets redrawn due to a change in some variables. Be careful that it might be the parent view that have some variables changes.
The best way to debug this kind of behaviour is to use the technique describe here, on Hacking with Swift. The idea is to identify what change caused a view to reload itself by printing print(Self._printChanges()) inside the body property. Note that by doing it, you will temporarily need to add an explicit return.
Then, observer the console and it most cases you will be able to identify the issue and refactor your code.
In my experience (does not seem to be the case here) this often happens when using #Environment(\.editMode) var editMode in both the view and parent view. For some reasons this value changes in both views when presenting a sheet, causing the view to be redrawn and the sheet closed.
I solved this problem by removing the codes below while setting to NavigationView on my homeView this week, which caused my subView's sheet automatically dismissed the first time showing.
NavigationView {...}
// .navigationViewStyle(StackNavigationViewStyle())

Unable to present ActionSheet via a NavigationBarItem in SwiftUI on an iPad

First, I have looked at a similar question, but it does not address my use case.
Present ActionSheet in SwiftUI on iPad
My issue is that I have a NavigationBarItem in my NavigationView that will toggle an ActionSheet when pressed. This behavior works properly when used on an iPhone.
However, when I use this on an iPad, both buttons on my screen will gray out and nothing happens. Clicking the buttons again will make them active (blue), but again, no sheet is presented.
Finally, if I select the button in the middle of the screen (Show Button), then an ActionSheet is properly presented on an iPad.
I have tested with Xcode 11 & iOS 13.5 and Xcode 12 & iOS 14. There is no change in behavior.
import SwiftUI
struct ContentView: View {
#State private var isButtonSheetPresented = false
#State private var isNavButtonSheetPresented = false
var body: some View {
NavigationView {
Button(action: {
// Works on iPad & iPhone
self.isButtonSheetPresented.toggle()
}) {
Text("Show Button")
}
.actionSheet(isPresented: $isButtonSheetPresented,
content: {
ActionSheet(title: Text("ActionSheet"))
})
.navigationBarTitle(Text("Title"),
displayMode: .inline)
.navigationBarItems(trailing:
Button(action: {
// Works on iPhone, fails on iPad
self.isNavButtonSheetPresented.toggle()
}) {
Text("Show Nav")
}
.actionSheet(isPresented: $isNavButtonSheetPresented,
content: {
ActionSheet(title: Text("ActionSheet"))
})
)
}
.navigationViewStyle(StackNavigationViewStyle())
}
}
Finally, this is how it appears on an iPad when clicking on "Show Nav":
This is a simplified setup for the screen where this issue occurs. I will need to retain the navigation settings shown, but have included them for clarity.
*** UPDATED ***
While it is not possible for the real app behind this, I did remove the .navigationViewStyle(StackNavigationViewStyle()) setting, which did make an ActionSheet appear, although in the wrong spot as seen below.
This also results in bizarre placement for the Button one accessed via "Show Button".
Yes, it is a bug, but probably different - that Apple does not allow to change anchor and direction of shown ActionSheet, because it is shown, but always to the right of originated control on iPad. To prove this it is enough to change location of button in Navigation
Here is example of placing at .leading position. Tested with Xcode 12 / iOS 14
.navigationBarItems(leading:
Button(action: {
// Works on iPhone, fails on iPad
self.isNavButtonSheetPresented.toggle()
}) {
Text("Show Nav")
}
.actionSheet(isPresented: $isNavButtonSheetPresented,
content: {
ActionSheet(title: Text("ActionSheet"))
})
)
Note: SwiftUI 2.0 .toolbar behaves in the same way, ie. has same bug.
This is an old question but if someone is interested in a turnaround that works on iOS 14:
I have two navigation bar trailing buttons inside .toolbar() and they should open action sheets. I placed an invisible "bar" at the top of the view to use it as an anchor:
var body: some View {
VStack {
HStack {
Spacer()
Color.clear.frame(width: 1, height: 1, alignment: .center)
.actionSheet(/*ActionSheet for first button*/)
Spacer().frame(width: 40)
Color.clear.frame(width: 1, height: 1, alignment: .center)
.actionSheet(/*ActionSheet for second button*/)
Spacer().frame(width: 40)
}.frame(height: 1)
}
}
Cons:
There's a tiny bar/extra space at the top, noticeable especially during scrolling (Maybe putting the Stack in the background with a Stack could remove it?).
You might need to adjust the Spacers' width to try and align the ActionSheets to their respective button.
You can't force the action sheet arrows to always point upwards, I tested this on another simulator and the rightmost ActionSheet had its arrow pointing to the right (the 'illusion' that it came from the button was still there)
Here's how it looks

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