NavigationView only shows Back button in SwiftUI - swiftui

I just create a swiftUI project and type this code on CntentView.swift. But the result is this image below. It was the same when I tried to run it on a real machine.
Why?
Environment:
Xcode Version 12.2(12B45b),
This is code of "Test13App.swift". Not edited any line.
Thank you very much for your comments. Since I only have iPad pro (and not have iPhone), I just knew this is a default behaviour of iPad split view now by your comments. Adding .navigationViewStyle(DefaultNavigationViewStyle()) right after NavigationView solved the problem like this
SwiftUI NavigationView on the iPad Pro
Sorry and Thanks very much!

If you want to change the style of your NavigationView on iPad making it similar to iPhone, you could use the:
.navigationViewStyle(StackNavigationViewStyle())
option in your NavigationView.
Like this:
struct ContentView: View {
var body: some View {
NavigationView{
Text("prova")
}
.navigationViewStyle(StackNavigationViewStyle())
}
}

When focused on both iPhone and iPad devices some developer's missing set the navigationview style type.
Set the NavigationView Style

Related

SwiftUI backwards compatibility with WatchOS 6: how to write body?

If I create a brand new xCode project with a WatchKit extension this is what I get created by default in the main app file:
struct WorkoutApp: App {
#available(watchOSApplicationExtension 7.0, *)
var body: some Scene {
WindowGroup {
NavigationView {
ContentView()
}
}
WKNotificationScene(controller: NotificationController.self, category: "myCategory")
}
}
However, many types such as Scene, WindowGroup and the #Main modifier are not available in WatchOS 6. I didn't find any example on how to create a watch kit extension with WatchOS 6 in SwiftUI. I either find examples that use the old way (with storyboards, without SwiftUI), or examples that use this construct or examples with storyboards.
How do I rearrange the project to compile and run for WatchOS 6?

iOS 14 AssistiveTouch Dwell Control sometimes not working on SwiftUI Buttons

I have a SwiftUI App which uses regular Button views and our customers use AssistiveTouch's DwellControl feature quite often. On iOS 13 DwellControl was working fine but on iOS 14 beta 8 DwellControl fails to be able click on those buttons.
The Buttons can be tapped by finger and clicked with the normal mouse but not with the DwellControl feature.
I have tried adding accessibility traits like isButton, but nothing works.
Has anyone encountered the same problem and has a solution or any insight at all? I know this is quite niche but any help is appreciated!
EDIT:
I have tested it with a very simple example, including one a Button and it works fine. It seems to be a side effect of some sorts in my specific App.
I have several ZStacks which show and hide some views like modals and popovers. Could this be the source of failure?
What I don't get is that the Buttons can be tapped and clicked... If a view was blocking the Button then this shouldn't be possible right?
I have tried Release and Debug builds which does not make a difference.
When DwellControl is activated and the cursor is on the Button that shall be clicked, tapping doesn't work either. But when the cursor is nowhere near the Button, tapping works fine.
I have send a report via Feedback to Apple.
EDIT:
I found the cause. ScrollView somehow prevents all DwellControl clicks from happening. That happens whenever a ScrollView is somewhere present in one of the Views.
Minimal example:
struct ContentView: View {
#State var show = false
var body: some View {
ZStack {
ScrollView {
Button(action: {
print("This should be printed but isn't....")
}, label: {
Text("Button in ScrollView")
})
}
}
}
}
I know its niche but maybe someone needs this.
There are other components which are affected and cause the same behaviour:
ScrollView
TextField
Slider
Stepper
UIViewRepresentable
For me this is a big issue, since our customers use DwellControl quite often.
EDIT:
This can be replicated in the newest iOS 14.2 beta 1:
import SwiftUI
#main
struct TempSwitUIApp: App {
#State private var text: String = "I am a text"
var body: some Scene {
WindowGroup {
Button(action: {
print("\(UUID()) \(self.text)")
}, label: {
Text("Print text to the console")
})
TextField("Hello", text: self.$text)
}
}
}
I updated my issue with Apple but haven't heard from them yet.

SwiftUI iOS 14 beta TextField 100% CPU

Using iOS 14 and Xcode 12.0 beta 6 if I try and use a simple TextField anywhere
import SwiftUI
struct ContentView: View {
#State private var name: String = "Tim"
var body: some View {
VStack {
TextField("Enter your name", text: $name)
Text("Hello, \(name)!")
}
}
}
the keyboard opens but then the CPU goes to 99%/100% and app is frozen.
Is this a known issue? How do I fix it?
This bug exists since the 14.0 betas and has not been fixed so far :/ I tried to search for workarounds or solutions but there seems to be none at the moment.
Once the user activates an input field, the CPU goes to 95%-100% and stays there until you actually quit the app.
I found some reason, If you use some .onAppear listener, When device keyboard is opened, application is being crazy if you set or change any #EnvironmentObject variable using .onAppear listener anywhere on your app. But it is not for all .onAppear... it was really weird. I searched piece by piece those when I have noticed.

Hide statusbar in swift ui, when .statusbar(hidden: true) does not work or react

I have an app that loads a tabbar with a view as initial screen, RecipeList(). Inside of RecipeList I call another view to show a recipe full screen. In RecipeList file I have code to show or hide the status bar checking if the recipe detail fullscreen view is loaded or not. It works perfectly if I preview it in xcode, BUT when I preview the code below, which is my Home() view file, and what I want to load as initial screen due to tabbar need, THEN the code inside of RecipeList to show or hide statusbar doesnt work anymore, and status bar is always on.
If i try to hide the statusbar in the code below, it works, but then is always off, something i dont want. Only wanna hide it for the fullscreen view.
I actually used this Introspect package from Github to hide the tabbar when the child view is loaded full screen, and i made it work!
SwiftUI hide TabBar in subview
https://github.com/siteline/SwiftUI-Introspect
Actually, I wonder if anyone has used Introspect to hide the statusbar like the tabbar. I tried to use it, but I am a rockie, I only know a bit of SwiftUI, no Swift, no view controller experience, nothing.
But I have a totally functional app with only this issue, and I am super frustrated not to have the skills to know why the tabbar view is forcing a persistent status bar.
Any help, please?
var body: some View {
ZStack {
Color("background2")
.edgesIgnoringSafeArea(.all)
TabView {
RecipeList().tabItem {
Image(systemName: "book.fill")
.font(.system(size: 24, weight: .bold))
Text("GalerĂ­a")
}
PostList(section: sectionData[0]).tabItem {
Image(systemName: "list.bullet")
.font(.system(size: 22, weight: .bold))
Text("Listado")
}
}
.accentColor(Color("accent"))
.introspectTabBarController { tabBarController in
// customize here the UITabBarViewController if you like
self.viewModel.tabBarController = tabBarController
}
}
}
I can suggest you using the #EnvironmentObject wrapper which basically allows you to use an object as global state. You can find fair amount of tutorials explaining how to do that and inject it in your initial view so that this object is accessible in the whole view hierarchy.
Once you have that global state set up, you can hide your status bar conditionally like this:
MyOutterWrapper {
Text("Some text")
}
.statusBar(hidden: myGlobalState.statusBarHidden)
If you are using NavigationView note that hiding the status bar works best if you set it up there (also assuming navigation view is your first view that appears).
Now all you got to do is inside your view set the variable to true when entering full screen and set it back to false when exiting. Hope that helps!
EDIT: Forgot to mention that hiding status bar as of June 26, 2020 only works if it's set on the initial view. You cannot change it later and that's the reason we set up this variable in order to go back and change the value dynamically.

What is the equivalent of WKInterfaceController.didAppear() in SwiftUI on watchOS?

I'm building an Apple Watch app, and there is code I want to run every time the app is brought to the foreground.
Previously, if I wanted to do this in a watchOS with a WKInterfaceController, I would put this code in didAppear().
In SwiftUI, there is onAppear(), but when I call that on watchOS it only seems to be called the first time the app loads up, so it behaves like WKInterfaceController.willActivate() instead. The app has just a single view.
If onAppear() is the equivalent of WKInterfaceController.willActivate(), is there a different SwiftUI function that is the equivalent of WKInterfaceController.didAppear()?
Here's my current example code:
import SwiftUI
struct ContentView: View {
var body: some View {
Text("Hello World").font(.footnote)
.onAppear {
print("onAppear called")
}
}
}
In the meantime, I am going to experiment with triggering what I need to do within the ExtensionDelegate, but I'm just trying to learn my way around SwiftUI on WatchOS, so knowing the answer to this would be helpful in the future.