The Edit menu's Undo/Redo displayed title does not reflect the setActionName in this demo SwiftUI macOS app. The undo/redo functionality works fine and the manager reports back that it has set the action title.
Why is the menu not updated?
autoenablesItems is true for NSApp.menu. When looping through all Windows in NSApp (just one window), the UndoManager (just one for the app) is the same instance as the one SwiftUI presents via Environment. Checking the undo item title via NSApp's reference also shows the item title is set, even though it is not displayed in the Edit menu.
struct ContentView: View {
#Binding var document: DocumentTestDocument
#Environment(\.undoManager) var undo
#StateObject var vm = VM()
#State var autoEnables = false
var body: some View {
VStack(spacing: 25) {
HStack {
Button("<") { vm.performUndo(undo: undo) }
.disabled(!(undo?.canUndo ?? true))
Button("Up") { vm.increment(undo: undo) }
Button("Down") { vm.decrement(undo: undo) }
Button(">") { vm.performRedo(undo: undo) }
.disabled(!(undo?.canRedo ?? true))
}
Text(String(vm.count))
.font(.title)
Text("MenuItemTitle \(vm.title)")
}
.controlSize(.large)
.font(.title3)
.frame(width: 400, height: 300)
.onAppear { DispatchQueue.main.async { autoEnables = NSApp.menu?.autoenablesItems ?? false } }
}
}
class VM: ObservableObject {
#Published var count = 0
#Published var title = ""
func increment(undo: UndoManager?) {
count += 1
undo?.registerUndo(withTarget: self, handler: { (targetSelf) in
targetSelf.decrement(undo: undo)
})
undo?.setActionName("Increment")
title = undo?.undoMenuItemTitle ?? "Nil"
}
func decrement(undo: UndoManager?) {
count -= 1
undo?.registerUndo(withTarget: self, handler: { (targetSelf) in
targetSelf.increment(undo: undo)
})
undo?.setActionName("Increment")
title = undo?.undoMenuItemTitle ?? "Nil"
}
func performUndo(undo: UndoManager?) {
undo?.undo()
}
func performRedo(undo: UndoManager?) {
undo?.redo()
}
}
For some reason, this is not implemented in the new SwiftUI App lifecycle. If you set up your Edit menu in a storyboard and configure the NSHostingView yourself, the Undo menu item titles will change correctly with your existing code. I sure hope this feature is on the way soon, because well-named undos are my favorite part of a polished Mac app!
Related
I want to have a Bool property, that represents that option key is pressed #Publised var isOptionPressed = false. I would use it for changing SwiftUI View.
For that, I think, that I should use Combine to observe for key pressure.
I tried to find an NSNotification for that event, but it seems to me that there are no any NSNotification, that could be useful to me.
Since you are working through SwiftUI, I would recommend taking things just a step beyond watching a Publisher and put the state of the modifier flags in the SwiftUI Environment. It is my opinion that it will fit in nicely with SwiftUI's declarative syntax.
I had another implementation of this, but took the solution you found and adapted it.
import Cocoa
import SwiftUI
import Combine
struct KeyModifierFlags: EnvironmentKey {
static let defaultValue = NSEvent.ModifierFlags([])
}
extension EnvironmentValues {
var keyModifierFlags: NSEvent.ModifierFlags {
get { self[KeyModifierFlags.self] }
set { self[KeyModifierFlags.self] = newValue }
}
}
struct ModifierFlagEnvironment<Content>: View where Content:View {
#StateObject var flagState = ModifierFlags()
let content: Content;
init(#ViewBuilder content: () -> Content) {
self.content = content();
}
var body: some View {
content
.environment(\.keyModifierFlags, flagState.modifierFlags)
}
}
final class ModifierFlags: ObservableObject {
#Published var modifierFlags = NSEvent.ModifierFlags([])
init() {
NSEvent.addLocalMonitorForEvents(matching: .flagsChanged) { [weak self] event in
self?.modifierFlags = event.modifierFlags
return event;
}
}
}
Note that my event closure is returning the event passed in. If you return nil you will prevent the event from going farther and someone else in the system may want to see it.
The struct KeyModifierFlags sets up a new item to be added to the view Environment. The extension to EnvironmentValues lets us store and
retrieve the current flags from the environment.
Finally there is the ModifierFlagEnvironment view. It has no content of its own - that is passed to the initializer in an #ViewBuilder function. What it does do is provide the StateObject that contains the state monitor, and it passes it's current value for the modifier flags into the Environment of the content.
To use the ModifierFlagEnvironment you wrap a top-level view in your hierarchy with it. In a simple Cocoa app built from the default Xcode template, I changed the application SwiftUI content to be:
struct KeyWatcherApp: App {
var body: some Scene {
WindowGroup {
ModifierFlagEnvironment {
ContentView()
}
}
}
}
So all of the views in the application could watch the flags.
Then to make use of it you could do:
struct ContentView: View {
#Environment(\.keyModifierFlags) var modifierFlags: NSEvent.ModifierFlags
var body: some View {
VStack {
Image(systemName: "globe")
.imageScale(.large)
.foregroundColor(.accentColor)
if(modifierFlags.contains(.option)) {
Text("Option is pressed")
} else {
Text("Option is up")
}
}
.padding()
}
}
Here the content view watches the environment for the flags and the view makes decisions on what to show using the current modifiers.
Ok, I found easy solution for my problem:
class KeyPressedController: ObservableObject {
#Published var isOptionPressed = false
init() {
NSEvent.addLocalMonitorForEvents(matching: .flagsChanged) { [weak self] event -> NSEvent? in
if event.modifierFlags.contains(.option) {
self?.isOptionPressed = true
} else {
self?.isOptionPressed = false
}
return nil
}
}
}
I have a MacOS app which has a lot of TextFields in many views; and one editor view which has to receive pressed keyboard shortcut, when cursor is above. But as I try, I cannot focus on a view which is not text enabled. I made a small app to show a problem:
#main
struct TestFocusApp: App {
var body: some Scene {
DocumentGroup(newDocument: TestFocusDocument()) { file in
ContentView(document: file.$document)
}
.commands {
CommandGroup(replacing: CommandGroupPlacement.textEditing) {
Button("Delete") {
deleteSelectedObject.send()
}
.keyboardShortcut(.delete, modifiers: [])
}
}
}
}
let deleteSelectedObject = PassthroughSubject<Void, Never>()
struct MysticView: View {
var body: some View {
ZStack {
Rectangle()
.foregroundColor(.gray.opacity(0.3))
}.focusable()
.onReceive(deleteSelectedObject) { _ in
print ("received")
}
}
}
enum FocusableField {
case wordTwo
case view
case editor
case wordOne
}
struct ContentView: View {
#Binding var document: TestFocusDocument
#State var wordOne: String = ""
#State var wordTwo: String = ""
#FocusState var focus: FocusableField?
var body: some View {
VStack {
TextField("one", text: $wordOne)
.focused($focus, equals: .wordOne)
TextEditor(text: $document.text)
.focused($focus, equals: .editor)
///I want to receive DELETE in any way, in a MystickView or unfocus All another text views in App to not delete their contents
MysticView()
.focusable(true)
.focused($focus, equals: .view)
.onHover { inside in
focus = inside ? .view : nil
/// focus became ALWAYS nil, even set to `.view` here
}
.onTapGesture {
focus = .view
}
TextField("two", text: $wordTwo)
.focused($focus, equals: .wordTwo)
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView(document: .constant(TestFocusDocument()))
}
}
Only first TextField became focused when I click or hover over MysticView
I can assign nil to focus, but it will not unfocus fields from outside this one view.
Is it a bug, or I missed something? How to make View focusable? To Unfocus all textFields?
I have a TabView thats using the swiftUI 2.0 PageTabViewStyle. Is there any way to disable the swipe to change pages?
I have a search bar in my first tab view, but if a user is typing, I don't want to give the ability to change they are on, I basically want it to be locked on to that screen until said function is done.
Here's a gif showing the difference, I'm looking to disable tab changing when it's full screen in the gif.
https://imgur.com/GrqcGCI
Try something like the following (tested with some stub code). The idea is to block tab view drag gesture when some condition (in you case start editing) happens
#State var isSearching = false
// ... other code
TabView {
// ... your code here
Your_View()
.gesture(isSearching ? DragGesture() : nil) // blocks TabView gesture !!
}
.tabViewStyle(PageTabViewStyle(indexDisplayMode: .always))
I tried Asperis's solution, but I still couldn't disable the swiping, and adding disabled to true didn't work since I want the child views to be interactive. The solution that worked for me was using Majid's (https://swiftwithmajid.com/2019/12/25/building-pager-view-in-swiftui/) custom Pager View and adding a conditional like Asperi's solution.
Majid's PagerView with conditional:
import SwiftUI
struct PagerView<Content: View>: View {
let pageCount: Int
#Binding var canDrag: Bool
#Binding var currentIndex: Int
let content: Content
init(pageCount: Int, canDrag: Binding<Bool>, currentIndex: Binding<Int>, #ViewBuilder content: () -> Content) {
self.pageCount = pageCount
self._canDrag = canDrag
self._currentIndex = currentIndex
self.content = content()
}
#GestureState private var translation: CGFloat = 0
var body: some View {
GeometryReader { geometry in
HStack(spacing: 0) {
self.content.frame(width: geometry.size.width)
}
.frame(width: geometry.size.width, alignment: .leading)
.offset(x: -CGFloat(self.currentIndex) * geometry.size.width)
.offset(x: self.translation)
.animation(.interactiveSpring(), value: currentIndex)
.animation(.interactiveSpring(), value: translation)
.gesture(!canDrag ? nil : // <- here
DragGesture()
.updating(self.$translation) { value, state, _ in
state = value.translation.width
}
.onEnded { value in
let offset = value.translation.width / geometry.size.width
let newIndex = (CGFloat(self.currentIndex) - offset).rounded()
self.currentIndex = min(max(Int(newIndex), 0), self.pageCount - 1)
}
)
}
}
}
ContentView:
import SwiftUI
struct ContentView: View {
#State private var currentPage = 0
#State var canDrag: Bool = true
var body: some View {
PagerView(pageCount: 3, canDrag: $canDrag, currentIndex: $currentPage) {
VStack {
Color.blue
Button {
canDrag.toggle()
} label: {
Text("Toogle drag")
}
}
VStack {
Color.red
Button {
canDrag.toggle()
} label: {
Text("Toogle drag")
}
}
VStack {
Color.green
Button {
canDrag.toggle()
} label: {
Text("Toogle drag")
}
}
}
}
}
Ok I think it is possible to block at least 99% swipe gesture if not 100% by using this steps:
and 2.
Add .gesture(DragGesture()) to each page
Add .tabViewStyle(.page(indexDisplayMode: .never))
SwiftUI.TabView(selection: $viewModel.selection) {
ForEach(pages.indices, id: \.self) { index in
pages[index]
.tag(index)
.gesture(DragGesture())
}
}
.tabViewStyle(.page(indexDisplayMode: .never))
Add .highPriorityGesture(DragGesture()) to all remaining views images, buttons that still enable to drag and swipe pages
You can also in 1. use highPriorityGesture but it completely blocks drags on each pages, but I need them in some pages to rotate something
For anyone trying to figure this out, I managed to do this by setting the TabView state to disabled.
TabView(selection: $currentIndex.animation()) {
Items()
}.disabled(true)
Edit: as mentioned in the comments this will disable everything within the TabView as well
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")
}
I've been looking through the docs with each beta but haven't seen a way to make a traditional paged ScrollView. I'm not familiar with AppKit so I am wondering if this doesn't exist in SwiftUI because it's primarily a UIKit construct. Anyway, does anyone have an example of this, or can anyone tell me it's definitely impossible so I can stop looking and roll my own?
You can now use a TabView and set the .tabViewStyle to PageTabViewStyle()
TabView {
View1()
View2()
View3()
}
.tabViewStyle(PageTabViewStyle())
As of Beta 3 there is no native SwiftUI API for paging. I've filed feedback and recommend you do the same. They changed the ScrollView API from Beta 2 to Beta 3 and I wouldn't be surprised to see a further update.
It is possible to wrap a UIScrollView in order to provide this functionality now. Unfortunately, you must wrap the UIScrollView in a UIViewController, which is further wrapped in UIViewControllerRepresentable in order to support SwiftUI content.
Gist here
class UIScrollViewViewController: UIViewController {
lazy var scrollView: UIScrollView = {
let v = UIScrollView()
v.isPagingEnabled = true
return v
}()
var hostingController: UIHostingController<AnyView> = UIHostingController(rootView: AnyView(EmptyView()))
override func viewDidLoad() {
super.viewDidLoad()
self.view.addSubview(self.scrollView)
self.pinEdges(of: self.scrollView, to: self.view)
self.hostingController.willMove(toParent: self)
self.scrollView.addSubview(self.hostingController.view)
self.pinEdges(of: self.hostingController.view, to: self.scrollView)
self.hostingController.didMove(toParent: self)
}
func pinEdges(of viewA: UIView, to viewB: UIView) {
viewA.translatesAutoresizingMaskIntoConstraints = false
viewB.addConstraints([
viewA.leadingAnchor.constraint(equalTo: viewB.leadingAnchor),
viewA.trailingAnchor.constraint(equalTo: viewB.trailingAnchor),
viewA.topAnchor.constraint(equalTo: viewB.topAnchor),
viewA.bottomAnchor.constraint(equalTo: viewB.bottomAnchor),
])
}
}
struct UIScrollViewWrapper<Content: View>: UIViewControllerRepresentable {
var content: () -> Content
init(#ViewBuilder content: #escaping () -> Content) {
self.content = content
}
func makeUIViewController(context: Context) -> UIScrollViewViewController {
let vc = UIScrollViewViewController()
vc.hostingController.rootView = AnyView(self.content())
return vc
}
func updateUIViewController(_ viewController: UIScrollViewViewController, context: Context) {
viewController.hostingController.rootView = AnyView(self.content())
}
}
And then to use it:
var body: some View {
GeometryReader { proxy in
UIScrollViewWrapper {
VStack {
ForEach(0..<1000) { _ in
Text("Hello world")
}
}
.frame(width: proxy.size.width) // This ensures the content uses the available width, otherwise it will be pinned to the left
}
}
}
Apple's official tutorial covers this as an example. I find it easy to follow and suitable for my case. I really recommend you check this out and try to understand how to interface with UIKit. Since SwiftUI is so young, not every feature in UIKit would be covered at this moment. Interfacing with UIKit should address most if not all needs.
https://developer.apple.com/tutorials/swiftui/interfacing-with-uikit
Not sure if this helps your question but for the time being while Apple is working on adding a Paging View in SwiftUI I've written a utility library that gives you a SwiftUI feel while using a UIPageViewController under the hood tucked away.
You can use it like this:
Pages {
Text("Page 1")
Text("Page 2")
Text("Page 3")
Text("Page 4")
}
Or if you have a list of models in your application you can use it like this:
struct Car {
var model: String
}
let cars = [Car(model: "Ford"), Car(model: "Ferrari")]
ModelPages(cars) { index, car in
Text("The \(index) car is a \(car.model)")
.padding(50)
.foregroundColor(.white)
.background(Color.blue)
.cornerRadius(10)
}
You can simply track state using .onAppear() to load your next page.
struct YourListView : View {
#ObservedObject var viewModel = YourViewModel()
let numPerPage = 50
var body: some View {
NavigationView {
List(viewModel.items) { item in
NavigationLink(destination: DetailView(item: item)) {
ItemRow(item: item)
.onAppear {
if self.shouldLoadNextPage(currentItem: item) {
self.viewModel.fetchItems(limitPerPage: self.numPerPage)
}
}
}
}
.navigationBarTitle(Text("Items"))
.onAppear {
guard self.viewModel.items.isEmpty else { return }
self.viewModel.fetchItems(limitPerPage: self.numPerPage)
}
}
}
private func shouldLoadNextPage(currentItem item: Item) -> Bool {
let currentIndex = self.viewModel.items.firstIndex(where: { $0.id == item.id } )
let lastIndex = self.viewModel.items.count - 1
let offset = 5 //Load next page when 5 from bottom, adjust to meet needs
return currentIndex == lastIndex - offset
}
}
class YourViewModel: ObservableObject {
#Published private(set) items = [Item]()
// add whatever tracking you need for your paged API like next/previous and count
private(set) var fetching = false
private(set) var next: String?
private(set) var count = 0
func fetchItems(limitPerPage: Int = 30, completion: (([Item]?) -> Void)? = nil) {
// Do your stuff here based on the API rules for paging like determining the URL etc...
if items.count == 0 || items.count < count {
let urlString = next ?? "https://somePagedAPI?limit=/(limitPerPage)"
fetchNextItems(url: urlString, completion: completion)
} else {
completion?(pokemon)
}
}
private func fetchNextItems(url: String, completion: (([Item]?) -> Void)?) {
guard !fetching else { return }
fetching = true
Networking.fetchItems(url: url) { [weak self] (result) in
DispatchQueue.main.async { [weak self] in
self?.fetching = false
switch result {
case .success(let response):
if let count = response.count {
self?.count = count
}
if let newItems = response.results {
self?.items += newItems
}
self?.next = response.next
case .failure(let error):
// Error state tracking not implemented but would go here...
os_log("Error fetching data: %#", error.localizedDescription)
}
}
}
}
}
Modify to fit whatever API you are calling and handle errors based on your app architecture.
Checkout SwiftUIPager. It's a pager built on top of SwiftUI native components:
If you would like to exploit the new PageTabViewStyle of TabView, but you need a vertical paged scroll view, you can make use of effect modifiers like .rotationEffect().
Using this method I wrote a library called VerticalTabView 🔝 that turns a TabView vertical just by changing your existing TabView to VTabView.
You can use such custom modifier:
struct ScrollViewPagingModifier: ViewModifier {
func body(content: Content) -> some View {
content
.onAppear {
UIScrollView.appearance().isPagingEnabled = true
}
.onDisappear {
UIScrollView.appearance().isPagingEnabled = false
}
}
}
extension ScrollView {
func isPagingEnabled() -> some View {
modifier(ScrollViewPagingModifier())
}
}
To simplify Lorenzos answer, you can basically add UIScrollView.appearance().isPagingEnabled = true to your scrollview as below:
VStack{
ScrollView(showsIndicators: false){
VStack(spacing: 0){ // to remove spacing between rows
ForEach(1..<10){ i in
ZStack{
Text(String(i))
Circle()
} .frame(width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height)
}
}
}.onAppear {
UIScrollView.appearance().isPagingEnabled = true
}
.onDisappear {
UIScrollView.appearance().isPagingEnabled = false
}
}