Some of the UI setups not working automatically with the Dark/Light mode change as the UIColor. For example shadow in layer. As I need to remove and drop shadow in dark and light mode, I need somewhere to put updateShadowIfNeeded() function. I know how to detect what is the mode currently:
func dropShadowIfNeeded() {
switch traitCollection.userInterfaceStyle {
case .dark: removeShadow()
case .light: dropShadowIfNotDroppedYet()
default: assertionFailure("Unknown userInterfaceStyle")
}
}
Now I put the function inside the layoutSubviews, since it gets called every time appearance change:
override func layoutSubviews() {
super.layoutSubviews()
dropShadowIfNeeded()
}
But this function is getting called A LOT. What is the proper function to trigger only if userInterfaceStyle changed?
SwiftUI
With a simple environment variable on the \.colorScheme key:
struct ContentView: View {
#Environment(\.colorScheme) var colorScheme
var body: some View {
Text(colorScheme == .dark ? "Its Dark" : "Its. not dark! (Light)")
}
}
UIKit
As it described in WWDC 2019 - Session 214 around 23:30.
As I expected, this function is getting called a lot including when colors changing. Along side with many other functions for ViewController and presentationController. But there is some especial function designed for that has a similar signature in all View representers.
Take a look at this image from that session:
Gray: Calling but not good for my issue, Green: Designed for this
So I should call it and check it inside this function:
override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?) {
super.traitCollectionDidChange(previousTraitCollection)
if traitCollection.hasDifferentColorAppearance(comparedTo: previousTraitCollection) {
dropShadowIfNeeded()
}
}
This will guarantee to be called just once per change.
if you are only looking for the initial state of the style, check out this answer here
I think this should get called significantly less often, plus the guard makes sure you only react to user interface style changes:
override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?) {
super.traitCollectionDidChange(previousTraitCollection)
guard previousTraitCollection?.userInterfaceStyle != traitCollection.userInterfaceStyle else {
return
}
dropShadowIfNeeded()
}
With RxSwift and ObjectiveC runtime, you can achieve it without inheritance
here is the encapsulated version:
import UIKit
import RxSwift
import RxCocoa
enum SystemTheme {
static func get(on view: UIView) -> UIUserInterfaceStyle {
view.traitCollection.userInterfaceStyle
}
static func observe(on view: UIView) -> Observable<UIUserInterfaceStyle> {
view.rx.methodInvoked(#selector(UIView.traitCollectionDidChange(_:)))
.map { _ in SystemTheme.get(on: view) }
.distinctUntilChanged()
}
}
Related
I have a fairly complex document type to work with. It is basically a bundle containing a set of independent documents of the same type, with various pieces of metadata about the documents. The data structure that represents the bundle is an array of structs, similar to this (there are several more fields, but these are representative):
struct DocumentData: Equatable, Identifiable, Hashable {
let id = UUID()
var docData: DocumentDataClass
var docName: String
var docFileWrapper: FileWrapper?
func hash(into hasher: inout Hasher) {
id.hash(into: &hasher)
}
static func ==(lhs: KeyboardLayoutData, rhs: KeyboardLayoutData) -> Bool {
return lhs.id == rhs.id
}
}
The window for the bundle is a master-detail, with a list on the left and, when one is selected, there is an edit pane for the document on the right. The FileWrapper is used to keep track of which files need to be written for saving, so it gets initialised on reading the relevant file, and reset when an undoable change is made. That is largely the only way that the DocumentData structure gets changed (ignoring explicit things like changing the name).
I've reached a point where a lot of things are working, but I'm stuck on one. There's a view inside the edit pane, several levels deep, and when I double-click it, I want a sheet to appear. It does so, but then disappears by itself.
Searching for ways to work this out, I discovered by using print(Self._printChanges()) at various points that the edit pane was being refreshed after showing the sheet, which meant that the parent disappeared. What I found was that the dependency that changed was the DocumentData instance. But, I then added a print of the DocumentData instance before the _printChanges call, and it is identical. I have also put in didSet for each field of DocumentData to print when they get set, and nothing gets printed, so I'm not sure where the change is happening.
So the question comes down to how I can work out what is actually driving the refresh, since what is claimed to be different is identical in every field.
There are some other weird things happening, such as dragging and dropping text into the view causing the whole top-level document array of DocumentData items to change before the drop gets processed and the data structures get updated, so there are things I am not understanding as clearly as I might like. Any guidance is much appreciated.
ADDED:
The view that triggers the sheet is fairly straightforward, especially compared to its enclosing view, which is where most of the interface code is. This is a slightly simplified version of it:
struct MyView: View, DropDelegate {
#EnvironmentObject var keyboardStatus: KeyboardStatus
#Environment(\.displayFont) var displayFont
#Environment(\.undoManager) var undoManager
var keyCode: Int
#State var modifiers: NSEvent.ModifierFlags = []
#State private var dragHighlight = false
#State private var activeSheet: ActiveSheet?
#State private var editPopoverIsPresented = false
// State variables for double click and drop handling
...
static let dropTypes = [UTType.utf8PlainText]
var body: some View {
ZStack {
BackgroundView(...)
Text(...)
}
.onAppear {
modifiers = keyboardStatus.currentModifiers
}
.focusable(false)
.allowsHitTesting(true)
.contentShape(geometry.contentPath)
.onHover { entered in
// updates an inspector view
}
.onTapGesture(count: 2) {
interactionType = .doubleClick
activeSheet = .doubleClick
}
.onTapGesture(count: 1) {
handleItemClick()
}
.sheet(item: $activeSheet, onDismiss: handleSheetReturn) { item in
switch item {
case .doubleClick:
DoubleClickItem(...) ) {
activeSheet = nil
}
case .drop:
DropItem(...) {
activeSheet = nil
}
}
}
.popover(isPresented: $editPopoverIsPresented) {
EditPopup(...)
}
.onDrop(of: KeyCap.dropTypes, delegate: self)
.contextMenu {
ItemContextMenu(...)
}
}
func handleItemClick() {
NotificationCenter.default.post(name: .itemClick, object: nil, userInfo: [...])
}
func handleEvent(event: KeyEvent) {
if event.eventKind == .dropText {
interactionType = .drop
activeSheet = .drop
}
else if event.eventKind == .replaceText {
...
handleItemDoubleClick()
}
}
func handleSheetReturn() {
switch interactionType {
case .doubleClick:
handleItemDoubleClick()
case .drop:
handleItemDrop()
case .none:
break
}
}
func handleItemDoubleClick() {
switch itemAction {
case .state1:
...
case .state2:
...
case .none:
// User cancelled
break
}
interactionType = nil
}
func handleItemDrop() {
switch itemDropAction {
case .action1:
...
case .action2:
...
case .none:
// User cancelled
break
}
interactionType = nil
}
// Drop delegate
func dropEntered(info: DropInfo) {
dragHighlight = true
}
func dropExited(info: DropInfo) {
dragHighlight = false
}
func performDrop(info: DropInfo) -> Bool {
if let item = info.itemProviders(for: MyView.dropTypes).first {
item.loadItem(forTypeIdentifier: UTType.utf8PlainText.identifier, options: nil) { (textData, error) in
if let textData = String(data: textData as! Data, encoding: .utf8) {
let event = ...
handleEvent(event: event)
}
}
return true
}
return false
}
}
Further edit:
I ended up rewiring the code so that the sheet belongs to the higher level view, which makes everything work without solving the question. I still don't understand why I get a notification that a dependency has changed when it is identical to what it was before, and none of the struct's didSet blocks are called.
Try removing the class from the DocumentData. The use of objects in SwiftUI can cause these kind of bugs since it’s all designed for value types.
Try using ReferenceFileDocument to work with your model object instead of FileDocument which is designed for a model of value types.
Try using sheet(item:onDismiss:content:) for editing. I've seen people have the problem you describe when they try to hack the boolean sheet to work with editing an item.
I have a very troubling problem. I have searched for days on how to solve it. I have some code that I want to run every time the app is opened, not just when the app is launched for the first time. I've basically tried everything available. I've tried scenePhase, I've tried AppDelegate, I've tried onAppear, I've tried init and custom extensions to the View class, I've even tried simply running a function in the view, but nothing is working. I'll show my code here.
#main
struct CouponDeckApp: App {
#UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
#Environment(\.scenePhase) private var scenePhase
var body: some Scene {
WindowGroup {
AppContentView()
}
}
}
struct AppContentView: View {
init() {
let userDefaults = UserDefaults.standard
if userDefaults.value(forKey: "hour") == nil { // 1
userDefaults.set(9, forKey: "hour") // 2
}
// 3
if userDefaults.value(forKey: "minute") == nil {
userDefaults.set(30, forKey: "minute")
}
}
#State var currentview: String = "Main"
var body: some View {
Group {
switch currentview {
case "Main":
MainView(currentview: $currentview)
case "Form":
FormView(currentview: $currentview)
case "Settings":
SettingsView(currentview: $currentview)
default:
if currentview.contains("Coupon") {
CouponView(currentview: $currentview)
}
else {
EditView(currentview: $currentview)
}
}
}
}
}
//MainView(), CouponView(), FormView(), etc.
I'm starting to suspect that the problem is with the switch statement in AppContentView that allows you to move between the different views.
Does anyone know:
A. Why this is happening,
B. How to fix it, or
C. Another alternative?
Thanks in advance!
P.S. I'm running my code on the simulator.
Here is a very simple way, using native scenePhase, I did not make it more complicated. You can use Preference method as well for better result! But onChange is good enough for this example:
struct ContentView: View {
#Environment(\.scenePhase) var scenePhase
var body: some View {
Text("Welcome to my App!")
.onAppear() { customFunction() }
.onChange(of: scenePhase) { newPhase in
if newPhase == .active {
customFunction()
}
}
}
}
func customFunction() {
print("App is opened!")
}
The simple problem was that it doesn't work when you close out of the app. I realized if you just exit the app but don't completely close out of it, it works just fine.
I also learned about the NotificationCenter's applications to this. By triggering a response when UIApplication sends out the willEnterForegroundNotification by using the onReceive method, you can trigger a response that way.
Do it in your AppDelegate's application(_:didFinishLaunchingWithOptions:).
An example function:
#ViewBuilder func returnView() -> some View {
if thisIsTrue == true {
SomeView()
} else {
AnotherView()
}
}
I've tried testing like this:
let testView = sut.returnView()
XCTAssert(testView is SomeView)
Which passes when there is only one possible type of view, but then fails as soon as there is a choice.
Any suggestions as to how I can unit test the output of this function?
The opaque return type some View means this function always returns exactly one type on all paths our of the function and that type conforms to View, so while it looks like you are returning two different things the ViewBuilder in fact collapses this into a single type that is generic with respect to the real return type. If you want to know what the opaque type really is you can just have the compiler tell you. For instance here is a playground. Note that this solution is fragile because changing the implementation of the function very likely will change the return type.
import SwiftUI
struct SomeView: View {
var body: some View { EmptyView() }
}
struct AnotherView: View {
var body: some View { Color.red}
}
#ViewBuilder func returnView() -> some View {
if true {
SomeView()
} else {
AnotherView()
}
}
let a = returnView()
print(type(of: a))
output:
_ConditionalContent<SomeView, AnotherView>
The solution that I went with was to not unit test the output of the function at all.
I created an enum in the view model that had cases that mapped to the different views and then used a computed property of this type to separate the business logic from the view logic.
enum ViewType {
case someView
case anotherView
}
var viewType: ViewType {
if thisIsTrue {
return .someView
} else {
return .anotherView
}
}
I can instantiate and test this in my unit testing.
Then in the view itself I created an #ViewBuilder variable and used a switch statement to map it to the view model viewType:
#ViewBuilder var view: some View {
switch viewModel.viewType {
case .someView:
SomeView()
case .anotherView:
AnotherView()
}
}
I hope this is helpful to someone else.
I'm (attempting) switching over my AppDelegate macOS app to the SwiftUI lifecycle - but can't seem to find out how to handle the CommandMenu. I just want to delete these default menu items (Fie, Edit, View, etc...). In the past, I would just delete them from the Storyboard - but I'm not using a storyboard here. Is there a way to delete these items in SwiftUI?
The items I want to delete:
I know how to add new items via:
.commands {
MyAppMenus()
}
But that just adds them inline with the existing menu items.
swiftUI -- override AppDelegate with your custom:
#main
struct PixieApp: App {
#NSApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
///........
}
code of appDelegate:
final class AppDelegate: NSObject, NSApplicationDelegate {
func applicationWillUpdate(_ notification: Notification) {
if let menu = NSApplication.shared.mainMenu {
menu.items.removeFirst{ $0.title == "Edit" }
menu.items.removeFirst{ $0.title == "File" }
menu.items.removeFirst{ $0.title == "Window" }
menu.items.removeFirst{ $0.title == "View" }
}
}
}
result:
Until SwiftUI adds more support for adjusting menus, I think you have to worry about SwiftUI reseting the NSApp.mainMenu whenever it updates a window.body. I haven't tried every method for adjusting the mainMenu, but of the methods I tried, the flaw was that SwiftUI seems to have no check for whether it last set NSApp.mainMenu or if something else did.
So however you are managing the menu, update it after SwiftUI has.
Use KVO and watch the NSApp for changes on .mainMenu. Then make your changes with a xib, or reseting the whole thing, or editing SwiftUI's menus.
Example:
#objc
class AppDelegate: NSObject, NSApplicationDelegate {
var token: NSKeyValueObservation?
func applicationDidFinishLaunching(_ notification: Notification) {
// Adjust a menu initially
if let m = NSApp.mainMenu?.item(withTitle: "Edit") {
NSApp.mainMenu?.removeItem(m)
}
// Must refresh after every time SwiftUI re adds
token = NSApp.observe(\.mainMenu, options: .new) { (app, change) in
// Refresh your changes
guard let menu = app.mainMenu?.item(withTitle: "Edit") else { return }
app.mainMenu?.removeItem(menu)
}
}
}
struct MarblesApp: App {
#NSApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
var body: some View {
//...
}
}
This seems to work in Xcode 13.4.1 with Swift 5 targeting macOS 12.3.
Hopefully Apple adds greater control soon. It seems Catalyst has other options. Or you can create a traditional AppKit app and insert the SwiftUI views into it.
You can remove command menu items through the AppDelegate file:
override func buildMenu(with builder: UIMenuBuilder) {
super.buildMenu(with: builder)
builder.remove(menu: .services)
builder.remove(menu: .format)
builder.remove(menu: .toolbar)
}
This thread on the Apple Developer forum might help as well: https://developer.apple.com/forums/thread/649096
CommandGroup(replacing: CommandGroupPlacement.appVisibility, addition: {})
I'm making a new Swift (3.0) framenwork which involves the use of a NSSearchField programmatically created, like the rest of the views.
This framenwork has the deployment target set to 10.10 and I found strange being not able to set the delegate metods for it. In fact NSSearchFieldDelegate only appear availabe in 10.11 on.
class PlistEditor: NSObject, NSOutlineViewDelegate, NSOutlineViewDataSource, NSTextFieldDelegate, NSSearchFieldDelegate {
var searchField : NSSearchField?
// more code..
init(tabItem: NSTabViewItem,
plistPath: String?) {
// more code..
let sf = NSSearchField(frame: NSMakeRect(80, 0, 80, 22))
self.searchField? = sf
// more code..
super.init()
// more code..
if #available(OSX 10.11, *) {
self.searchField?.delegate = self
} else {
// Fallback on earlier versions
}
// more code
}
}
Ok, I thought it was inherent from NStextField, and maybe I can access the cell and set up using the superclass delegate, but unfurtunately I cannot found a way to do that.
What I need is to be able to receive NSText/NSTextField notification in 10.10. How can I do this?
EDITED:
added more info on how is made plus some picts
Without providing more info, i am guessing you forgot to declare that your class is conforming to the NSSearchFieldDelegate.
See the example below, how to set it up for example a viewController. You just create an extension for your vc, and declare it to conform to the delegate.
class SearchViewController: NSViewController {
let searchField: NSSearchField? = NSSearchField(frame: .zero)
override func viewWillAppear() {
super.viewWillAppear()
if #available(OSX 10.11, *) {
self.searchField?.delegate = self
} else {
// Fallback on earlier versions
}
}
}
extension SearchViewController: NSSearchFieldDelegate {
func searchFieldDidStartSearching(_ sender: NSSearchField) {
print("didStart")
}
func searchFieldDidEndSearching(_ sender: NSSearchField) {
print("didEnd")
}
}
EDIT:
To capture the textDidChange event in earlier versions of Mac OS, you need to subclass NSSearchField and override textDidChange function. Every time a change happens in the searchField, it will call the function for you.
class DLSearchField: NSSearchField {
override func textDidChange(_ notification: Notification) {
Swift.print("textDidChange")
}
}