Select SwiftUI cell in Popover - popover

I am trying to make a popover in SwiftUI using a UIHostingController with a list that can be tapped. First, the user name and password should be filled in, and then the user role should be tapped in the list, and the popover should be dismissed when the save button is tapped.
Also, the save button in the navigation bar should be disabled until the user information has been verified.
The Xcode playground for this can be fetched from my GitHub repository https://github.com/imyrvold/Popover
To be able to use the AddUserView as a rootView in UIHostingController, I had to use an Xcode storyboard, and add it to the Resources in the Xcode Playground.
import SwiftUI
import Combine
public struct AddUserView : View {
#ObjectBinding public var loginInfo: LoginInfo
#EnvironmentObject var viewModel: RoleViewModel
#State var selectedRole: Role? = nil
#Environment(\.isPresented) var isPresented: Binding<Bool>?
public var body: some View {
NavigationView {
VStack {
TextField(self.$loginInfo.firstName, placeholder: Text("First Name"))
TextField(self.$loginInfo.lastName, placeholder: Text("Last Name"))
TextField(self.$loginInfo.email, placeholder: Text("Email"))
SecureField(self.$loginInfo.password, placeholder: Text("Password"))
Divider()
List(self.viewModel.roles) { role in
RoleCell(role: role).tapAction {
self.selectedRole = role
}
}
}
.padding()
.navigationBarTitle(Text("Add User"))
.navigationBarItems(trailing:
Button(action: {
self.saveAction()
self.isPresented?.value = false
}) {
Text("Save")
})//.disabled(!self.loginInfo.isValid)
}
}
// MARK:- Action methods
func saveAction() {
}
}
The first problem I have is that when I uncomment the disabled(!self.loginInfo.isValid), all the TextField's are also disabled. Not sure if that is a bug in SwiftUI?
I also want to have the rolecell set the checkmark on the cell when tapped, but so far I have been unable to figure out how to do that.
And how can I dismiss the Popover when the save button is tapped?
(When running the playground, have to click the start playground a second time to run properly, the first time the Save popover doesn't work).

Have you tried this
.navigationBarItems(trailing:
Button(action: {
self.saveAction()
self.isPresented?.value = false
}) {
Text("Save")
}.disabled(!self.loginInfo.isValid))

Related

SwiftUI Tooltip on hover

SwiftUI provides the .help() modifier but it is too small, cannot be customised and takes too long to appear to actually serve its intended purpose. I would like to create a tooltip that appears immediately on hover and is larger, similar to the one that appears on hovering on an icon in the Dock.
Something like this:
Is this possible to create from SwiftUI itself? I've tried using a popover but it prevents hover events from propagating once its open, so I can't make it close when the mouse moves away.
Solution #1: Check for .onHover(...)
Use the .onHover(perform:) view modifier to toggle a #State property to keep track of whether your tooltip should be displayed:
#State var itemHovered: Bool = false
var body: some View {
content
.onHover { hover in
itemHovered = hover
}
.overlay(
Group {
if itemHovered {
Text("This is a tooltip")
.background(Color.white)
.foregroundColor(.black)
.offset(y: -50.0)
}
}
)
}
Solution #2: Make a Tooltip Wrapper View
Create a view wrapper that creates a tooltip view automatically:
struct TooltipWrapper<Content>: View where Content: View {
#ViewBuilder var content: Content
var hover: Binding<Bool>
var text: String
var body: some View {
content
.onHover { hover.wrappedValue = $0 }
.overlay(
Group {
if hover.wrappedValue {
Text("This is a tooltip")
.background(Color.white)
.foregroundColor(.black)
.offset(y: -50.0)
}
}
)
}
}
Then you can call with
#State var hover: Bool = false
var body: some View {
TooltipWrapper(hover: $hover, text: "This is a tooltip") {
Image(systemName: "arrow.right")
Text("Hover over me!")
}
}
From this point, you can customize the hover tooltip wrapper to your liking.
Solution #3: Use my Swift Package
I wrote a 📦 Swift Package that makes SwiftUI a little easier for personal use, and it includes a tooltip view modifier that boils the solution down to:
import ShinySwiftUI
#State var showTooltip: Bool = false
var body: some View {
MyView()
.withTooltip(present: $showTooltip) {
Text("This is a tooltip!")
}
}
Notice you can provide your own custom views in the tooltip modifier above, like Image or VStack. Alternatively, you could use HoverView to get a stateful hover variable to use solely within your view:
HoverView { hover in
Rectangle()
.foregroundColor(hover ? .red : .blue)
.overlay(
Group {
if hover { ... }
}
)
}

SwiftUI Sheet Crash with Occasional Warning about Modifying State

I have a SwiftUI button that, when clicked, a sheet displays a confirmation modal. When a button is clicked in that modal to confirm, I make a save to Core Data.
I'm getting one or all of a few nasty results:
The sheet just hangs and becomes unresponsive.
I get a warning: "Modifying state during view update, this will cause undefined behavior".
I get a crash.
Obviously I'm modifying the state becomes I'm deleting a thing, but I'm unclear on how to do this right.
Here is my view where I click delete:
struct MyView: View{
#State var showDeleteModal = false
var body: some View{
Button("Delete"){
showDeleteModal.toggle()
}
.sheet(isPresented: self.$showDeleteModal) {
ModalView(confirm: {
self.showDeleteModal.toggle()
//Save the object in my Core Data stuff
model.saveThing(thing: thing)
})
}
}
}
And here's my modal that has a callback function to confirm the deletion:
struct ModalView: View {
var confirm:() -> Void
var body: some View {
Button("Confirm"){
confirm()
}
}
}
How do I hide the modal and make the save (which removes the view from the screen) without interfering with SwiftUI's state?
I'd suggest using sheet(isPresented:onDismiss:content:) and calling model.saveThing in onDismiss:
struct MyView: View {
#State var showDeleteModal = false
var body: some View {
Button("Delete") {
showDeleteModal.toggle()
}
.sheet(isPresented: self.$showDeleteModal, onDismiss: onDismiss) {
ModalView()
}
}
func onDismiss() {
model.saveThing(thing: thing)
}
}
Then you can dismiss the sheet without knowing the parent's state - just use #Environment(\.presentationMode):
struct ModalView: View {
#Environment(\.presentationMode) private var presentationMode
var body: some View {
Button("Confirm") {
presentationMode.wrappedValue.dismiss()
}
}
}
Note: as sheet can be closed without interacting with the confirm button, you can detect how it was closed using another #State variable - see:
SwiftUI: How to show an alert after a sheet is closed?

EnvironmentObject refresh/hand over problems using NavigationLink

I am currently developing an app for watchOS 6 (independent app) using Swift/SwiftUI in XCode 11.5 on macOS Catalina.
Before a user can use my app, a configuration process is required. As the configuration process consists of several different views which are shown one after each other, I implemented this by using navigation links.
After the configuration process has been finished, the user should click on a button to return to the "main" app (main view). For controlling views which are on the same hierarchical level, my plan was to use an EnvironmentObject (as far as I understood, an EnvironmentObject once injected is handed over to the subviews and subviews can use the EnvironmentObject) in combination with a "controlling view" which controls the display of the views. Therefore, I followed the tutorial: https://blckbirds.com/post/how-to-navigate-between-views-in-swiftui-by-using-an-environmentobject/
This is my code:
ContentView.swift
struct ContentView: View {
var body: some View {
ContentViewManager().environmentObject(AppStateControl())
}
}
struct ContentViewManager: View {
#EnvironmentObject var appStateControl: AppStateControl
var body: some View {
VStack {
if(appStateControl.callView == "AppConfig") {
AppConfig()
}
if(appStateControl.callView == "AppMain") {
AppMain()
}
}
}
}
AppStateControl.swift
class AppStateControl: ObservableObject {
#Published var callView: String = "AppConfig"
}
AppConfig.swift
struct AppConfig: View {
#EnvironmentObject var appStateControl: AppStateControl
var body: some View {
VStack {
Text("App Config Main")
NavigationLink(destination: DetailView1().environmentObject(appStateControl)) {
Text("Show Detail View 1")
}
}
}
}
struct DetailView1: View {
#EnvironmentObject var appStateControl: AppStateControl
var body: some View {
VStack {
Text("App Config Detail View 1")
NavigationLink(destination: DetailView2().environmentObject(appStateControl)) {
Text("Show Detail View 2")
}
}
}
}
struct DetailView2: View {
#EnvironmentObject var appStateControl: AppStateControl
var body: some View {
VStack {
Text("App Config Detail View 2")
Button(action: {
self.appStateControl.callView = "AppMain"
}) {
Text("Go to main App")
}
}
}
}
AppMain.swift
struct AppMain: View {
var body: some View {
Text("Main App")
}
}
In a previous version of my code (without the handing over of the EnvironmentObject all the time) I got a runtime error ("Thread 1: Fatal error: No ObservableObject of type AppStateControl found. A View.environmentObject(_:) for AppStateControl may be missing as an ancestor of this view.") caused by line 41 in AppConfig.swift. In the internet, I read that this is probably a bug of NavigationLink (see: https://www.hackingwithswift.com/forums/swiftui/environment-object-not-being-inherited-by-child-sometimes-and-app-crashes/269, https://twitter.com/twostraws/status/1146315336578469888). Thus, the recommendation was to explicitly pass the EnvironmentObject to the destination of the NavigationLink (above implementation). Unfortunately, this also does not work and instead a click on the button "Go to main App" in "DetailView2" leads to the view "DetailView1" instead of "AppMain".
Any ideas how to solve this problem? To me, it seems that a change of the EnvironmentObject in a view called via a navigation link does not refresh the views (correctly).
Thanks in advance.
One of the solutions is to create a variable controlling whether to display a navigation stack.
class AppStateControl: ObservableObject {
...
#Published var isDetailActive = false // <- add this
}
Then you can use this variable to control the first NavigationLink by setting isActive parameter. Also you need to add .isDetailLink(false) to all subsequent links.
First link in stack:
NavigationLink(destination: DetailView1().environmentObject(appStateControl), isActive: self.$appStateControl.isDetailActive) {
Text("Show Detail View 1")
}
.isDetailLink(false)
All other links:
NavigationLink(destination: DetailView2().environmentObject(appStateControl)) {
Text("Show Detail View 2")
}
.isDetailLink(false)
Then just set isDetailActive to false to pop all your NavigationLinks and return to the main view:
Button(action: {
self.appStateControl.callView = "AppMain"
self.appStateControl.isDetailActive = false // <- add this
}) {
Text("Go to main App")
}

SwiftUI: Action of custom button not triggered

Testing some stuff on tvOS with SwiftUI. When i add a custom style to a button, the "action" of the button is not getting triggered. In this example, i wanna print "pressed", but adding functions is not working either.
Is it possible to implement an custom action trigger aswell or what am i doing wrong?
For clarification why i wanna have a custom button style.
When i dont use any buttonstyle, the "action" is working, but the "onFocusChange" function is never getting called. WHICH I NEED!
But.. when i use a buttonstyle, the onFocusChange is working but the action is not.....
struct CustomButton: View {
#State private var buttonFocus: Bool = false
var body: some View {
VStack(alignment: .center){
Button(action: {
print("pressed")
})
{
Text("Save")
}
.buttonStyle(TestButtonStyle(focused: buttonFocus))
.focusable(true, onFocusChange: { (changed) in
self.buttonFocus.toggle()
})
}
}
}
Buttonstyle:
struct TestButtonStyle: ButtonStyle {
let focused: Bool
public func makeBody(configuration: TestButtonStyle.Configuration) -> some View {
configuration.label
.foregroundColor(.white)
.background(RoundedRectangle(cornerRadius: 5).fill(Color.red))
.scaleEffect(focused ? 1.5 : 1.0)
}
}
Its working with SwiftUI 2.0 now.
You can use the following environment Object on your View you want to be focused.
Also, add a State or Binding to bubble up to your parent view.
#Environment(\.isFocused) var isFocused: Bool
#Binding var focusedValue: Bool
Then, you can call the following modifier, which gets called when the View is getting focused or not. Here you change your Binding or State variable.
.onChange(of: isFocused, perform: { value in
self.focusedValue = value
})
Finally, you can use your Binding or State to modify your View.
.scaleEffect(self.focused ? 1.1 : 1)
.animation(.linear(duration: 0.1))

Can't do a Simple Navigate to View and back SwiftUI Navigation Bar Button

I'm trying to do a simple SwiftUI navigation from one view to another and back using
a bar button item. I have tried three different approaches to calling a new view.
Using a Button in the body view works, but using NavigationBarItems in the navigation
bar fails in two different ways.
Here's the start view:
struct ContentView: View {
#State private var showSecondView = false
var body: some View {
NavigationView {
VStack {
Text("This is the content view")
.navigationBarTitle("Nav Title")
//this works ONCE only:
.navigationBarItems(trailing: Button(action: {self.showSecondView.toggle()}) {
Text("SecondView")
})
//this always fails on return to contentview with error:
//Tried to pop to a view controller that doesn't exist
// .navigationBarItems(trailing:
// NavigationLink(destination: SecondView()) {
// Text("SecondNav")
// }
// )
//This always works:
Button(action: {self.showSecondView.toggle()} ) {
Text("Call Modal Second View")
}.padding()
Text(self.showSecondView ? "true" : "false")
}.sheet(isPresented: $showSecondView) {
SecondView()
}
}
}
}
If I use a NavigationLink in the NavigationBarItems, the SecondView is displayed, but
on return to the ContentView, it crashes with the error: "Tried to pop to a view
controller that doesn't exist"
If I use a Button in the NavigationBarItems, the transition to the SecondView works
once and only once. The return to ContentView works but the button no longer functions.
Interestingly, If the first action taken is with the Button in the Body, the
NavigationBarItem does not work even once.
And the simple SecondView:
struct SecondView: View {
#Environment(\.presentationMode) var presentation
var body: some View {
NavigationView {
VStack{
Text("This is the second view")
Button(action: { self.presentation.wrappedValue.dismiss()}) {
Text("Dismiss Modal")
}.padding()
}
}
}
}
I'm confused. Any guidance would be appreciated. Xcode 11.2 (11B44), Catalina 10.15
This is still an issue for me, I am having the same issue with popover (Modal) presentation and pushing Second controller via NavigationLink in navigationBarItems.
This is a really serious bug. The only way it works correctly is when the NavigationLink is inside NavigationView content and not navigationBarItems.
This is a really breaking as NavigationBar buttons are suppose to work that way.
I came across this issue today when I updated my Xcode to 11.2. According to this post it seems to be a bug with 13.2. I tested it on my actual iPhone X, which is still running 13.1.2, and it works just fine there.

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