In a UIKit application, removing a view from the hierarchy is straightforward—we simply call myView.removeFromSuperview(). This not only removes myView from the UI but also deallocates any associated memory.
Now that I'm transitioning to SwiftUI, I'm struggling to understand the recommended way to remove a view from the hierarchy, given SwiftUI's declarative nature.
I understand that in SwiftUI, we declare everything that should be displayed. However, once a view is rendered, what is the correct way to remove it? Should all UI elements be conditionally controlled to determine whether they appear or not?
Below is an example of how I’m currently handling this, but it doesn’t feel like the right approach for dynamically removing a view at runtime.
Can someone guide me on the best way to remove views in SwiftUI?
struct ContentView: View {
@State private var isVisible = true
var body: some View {
VStack {
if isVisible { // set this to false to remove TextView?
Text("Hello, SwiftUI!")
.padding()
}
Button("Toggle View") {
...
}
}
}
}
Explore the various UI frameworks available for building app interfaces. Discuss the use cases for different frameworks, share best practices, and get help with specific framework-related questions.
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I'm trying to determine if it’s possible to detect when a user interacts with a Slide Over window while my app is running in the background on iPadOS. I've explored lifecycle methods such as scenePhase and various UIApplication notifications (e.g., willResignActiveNotification) to detect focus loss, but these approaches don't seem to capture the event reliably. Has anyone found an alternative solution or workaround for detecting this specific state change? Any insights or recommended practices would be greatly appreciated.
So I am looking to use a custom NSWindow application (so I can implement some enhanced resizing/dragging behavior which is only possible overriding NSWindow).
The problem is my whole application is currently SwiftUI-based (see the project here: https://github.com/msdrigg/Roam/blob/50a2a641aa5f2fccb4382e14dbb410c1679d8b0c/Roam/RoamApp.swift).
I know there is a way to make this work by dropping my @main SwiftUI app and replacing it with a SwiftUI root view hosted in a standard AppKit root app, but that feels like I'm going backwards.
Is there another way to get access (and override) the root NSWindow for a SwiftUI app?
I am experiencing memory leaks in my iOS app that seem to be related to an issue between UIInputView and _UIInputViewContent. After using the memory graph, I'm seeing that instances of these objects aren't being deallocated properly.
The UIInputViewController whichs holds the inputView is being deallocated properly along with its subviews.I have tried to remove all of UIInputViewController's subviews and their functions but the uiInputView is not being deallocated.
The current setup of my app is a collectionView with multiple cells,each possessing a textfield with holds a UIInputViewController.When i scroll up or down,the views are being reused as expected and the number of UIInputViewController stays consistent with the number of textfields.However the number of inputView keeps increasing referencing solely _UIInputViewContent.
class KeyboardViewController: UIInputViewController {
// Callbacks
var key1: ((String) -> Void)?
var key2: (() -> Void)?
var key3: (() -> Void)?
var key4: (() -> Void)?
private lazy var buttonTitles = [
["1", "2", "3"],
["4", "5", "6"],
["7", "8", "9"]
]
override func viewDidLoad() {
super.viewDidLoad()
setupKeyboard()
}
lazy var mainStackView: UIStackView = {
let mainStackView = UIStackView()
mainStackView.axis = .vertical
mainStackView.distribution = .fillEqually
mainStackView.spacing = 16
mainStackView.translatesAutoresizingMaskIntoConstraints = false
return mainStackView
}()
private func setupKeyboard() {
let keyboardView = UIView(frame:CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: 279.0))
keyboardView.addSubview(mainStackView)
NSLayoutConstraint.activate([
mainStackView.topAnchor.constraint(equalTo: keyboardView.topAnchor, constant: 16),
mainStackView.leadingAnchor.constraint(equalTo: keyboardView.leadingAnchor, constant: 0),
mainStackView.trailingAnchor.constraint(equalTo: keyboardView.trailingAnchor, constant: -24),
mainStackView.bottomAnchor.constraint(equalTo: keyboardView.bottomAnchor, constant: -35)
])
// Create rows
for (_, _) in buttonTitles.enumerated() {
let rowStackView = UIStackView()
rowStackView.axis = .horizontal
rowStackView.distribution = .fillEqually
rowStackView.spacing = 1
// Create buttons for each row
for title in rowTitles {
let button = createButton(title: title)
rowStackView.addArrangedSubview(button)
}
mainStackView.addArrangedSubview(rowStackView)
}
self.view = keyboardView
}
private func createButton(title: String) -> UIButton {
switch title {
///returns a uibutton based on title
}
}
// MARK: - Button Actions
@objc private func numberTapped(_ sender: UIButton) {
if let number = sender.title(for: .normal) {
key1?(number)
}
}
@objc private func key2Called() {
key2?()
}
@objc private func key3Called() {
key3?()
}
@objc private func key4Called() {
key4?()
}
deinit {
// Clear any strong references
key1 = nil
key2 = nil
key3 = nil
key4 = nil
for subview in mainStackView.arrangedSubviews {
if let stackView = subview as? UIStackView {
for button in stackView.arrangedSubviews {
(button as? UIButton)?.removeTarget(self, action: nil, for: .allEvents)
}
}
}
mainStackView.removeFromSuperview()
}
}
Environment
iOS 16.3
Xcode 18.3.1
Any insights would be greatly appreciated as this is causing noticeable memory growth in my app over time.
In order to make referencing keys for localized strings a little more reliable, our application references generated constants for localized string keys:
This eliminates the potential for developers to misspell a key when referencing a localized strings. And because these constants are automatically generated by the exact same process that provides localized strings for the application, each and every constant is guaranteed to have a localized string associated with it.
I’m currently attempting to implement something similar for the localized strings referenced by our new App Intents. Our initial release of App Intent functionality is simply using string literals to reference localized strings:
However, I am running into several issues when trying to reference the string keys as a constant. The closest I managed to get was defining the constant as either a LocalizationValue or as a StaticString and referencing the constant while initializing the LocalizedStringResource. With this approach, I see no errors from Xcode until I try and compile. What’s more is that the wording of the error being thrown is quite peculiar:
As you can see with the sample code above, I am clearly calling LocalizedStringResource’s initializer directly as Indicated by the error.
Is what I’m trying to do even possible with App Intents? From my research, it does look like iOS app localization is moving more towards using string literals for localized strings. Like with String Catalog’s ability to automatically generate entries from strings referenced in UI without the need for a key. However, we’d prefer to use constants if possible for the reasons listed above.
I had a problem with my app (or in my setup) and searching the web I found a very simple code where part of my problem occurs.
I create a new Multiplatform App and
paste this code in ContentView.
import SwiftUI
struct ContentView: View {
var body: some View {
NavigationStack {
VStack {
Text("Navigation article")
.font(.title)
.padding()
NavigationLink("Go to the second view", destination: SecondView())
.padding()
}
.navigationTitle("First View")
}
}
}
struct SecondView: View {
var body: some View {
Text("This is the Second view")
.font(.headline)
.padding()
.navigationTitle("Second View")
}
}
run on iPhone/ iOS no problem
run on a Mac/macOS
Going from view 1 to view 2 work, the back arrow on view 2 is there, and it is working but the second time I go to the view 2, the back arrow is gone.
after looking closely I can see the Arrow Underneath the S of SecondView.
I have tried many things and could not make it work.
I post this in a HackingWithSwift forum and somebody tried the code and said it work. so it seems the problem could be related to my setup but I create another user in my computer , same problem and tried it on my another computer, same problem.
Topic:
UI Frameworks
SubTopic:
SwiftUI
I’m having a weird UIKit problem. I have a bunch of views in a UIScrollView and I add a UIContextMenuInteraction to all of them when the view is first loaded. Because they're in a scroll view, only some of the views are initially visible.
The interaction works great for any of the views that are initially on-screen, but if I scroll to reveal new subviews, the context menu interaction has no effect for those.
I used Xcode's View Debugger to confirm that my interaction is still saved in the view's interactions property, even for views that were initially off-screen and were then scrolled in.
What could be happening here?
Goal : Drag a sphere across the room and track it's position
Problem: The gesture seems to have no effect on the sphere ModelEntity.
I don't know how to properly attach the gesture to the ModelEntity. Any help is great. Thank you
import SwiftUI
import Foundation
import UIKit
@main
struct testApp: App {
@State var immersionStyle:ImmersionStyle = .mixed
var body: some Scene {
ImmersiveSpace {
ContentView()
}
.immersionStyle(selection: $immersionStyle, in: .mixed, .full, .progressive)
}
}
struct ContentView: View {
@State private var lastPosition: SIMD3? = nil
@State var subscription: EventSubscription?
@State private var isDragging: Bool = false
var sphere: ModelEntity {
let mesh = MeshResource.generateSphere(radius: 0.05)
let material = SimpleMaterial(color: .blue, isMetallic: false)
let entity = ModelEntity(mesh: mesh, materials: [material])
entity.generateCollisionShapes(recursive: true)
return entity
}
var drag: some Gesture {
DragGesture()
.onChanged { _ in self.isDragging = true }
.onEnded { _ in self.isDragging = false }
}
var body: some View {
RealityView { content in
//1. Anchor Entity
let anchor = AnchorEntity(world: SIMD3<Float>(0, 0, -1))
let ball = sphere
//2. add anchor to sphere
anchor.addChild(ball)
content.add(anchor)
subscription = content.subscribe(to: SceneEvents.Update.self) { event in
let currentPosition = ball.position(relativeTo: nil)
if let last = lastPosition, last != currentPosition {
print("Sphere moved from \(last) to \(currentPosition)")
}
lastPosition = currentPosition
}
}
.gesture(drag)
}
}
For my macOS app, I'm trying to change the mouse cursor to a pointing hand while hovering over a specific view. However, when the view is scaled with an animation triggered by hovering (using .scaleEffect() and .animation()), the cursor doesn't change as expected. Is there any workaround to fix this?
This is a sample code:
struct ContentView: View {
@State private var hovering = false
var body: some View {
VStack {
Text("Hover me")
.padding()
.background(hovering ? Color.blue : Color.gray)
.scaleEffect(hovering ? 1.2 : 1.0)
.animation(.linear(duration: 0.2), value: hovering)
.onHover { hovering in
self.hovering = hovering
if hovering {
NSCursor.pointingHand.push()
} else {
NSCursor.pop()
}
}
}
.frame(width: 200, height: 200)
}
}
This is how it works:
As you can see, when the pointer enters the view, the cursor changes momentarily before reverting back to the arrow icon.
I also tried using NSTrackingArea with an NSView placed over the view, but it did not solve the issue. It might be that the combination of .scaleEffect() and .animation() is causing a forced cursor reset (possibly related to the use of NSWindow.disableCursorRects() or something similar). However, I'm not entirely sure.
Any insights or suggestions would be greatly appreciated. Thanks!
I Am interested in coding, and built my fist app that is an app that has a picture of Niagara Falls with corner radius of 10, But, every time I start the build, it says: Thread 1: EXC_BAD_ACCESS (code=2, address=0x16b123f20) not sure what to do now.
Since beta 4, Using TipKit causes the app to crash.
This was not the case in Beta 3.
My app uses UIKit
Xcode has been downloading many similar crash reports for my app for some time now, related to an index out of range runtime exception when accessing a Swift array. The crashes always happen in methods triggered by user input or during menu item validation when I try to access the data source array by using the following code to determine the indexes of the relevant table rows:
let indexes = clickedRow == -1 || selectedRowIndexes.contains(clickedRow) ? selectedRowIndexes : IndexSet(integer: clickedRow)
I was never able to reproduce the crash until today. When the app crashed in the Xcode debugger, I examined the variables clickedRow and selectedRowIndexes.first, which were 1 and 0 respectively. What's interesting: the table view only contained one row, so clickedRow was effectively invalid. I tried to reproduce the issue several times afterwards, but it never happened again.
What could cause this issue? What are the circumstances where it is invalid? Do I always have to explicitly check if clickedRow is within the data source range?
App update in which there were no changes regarding the widget. Just after it updated, the widget turns black in some cases. It also appears black in the widget gallery. Removing and adding it again did not work in this case, only after an iOS restart it works fine again
This is the log
2025-03-20 02:14:05.961611 +0800 Content load failed: unable to find or unarchive file for key: [com.aa.bb::com.aa.bb.widget:cc_widget:systemMedium::360.00/169.00/23.00:(null)~(null)] on no host. The session may still produce one shortly. Error: Using url file:///private/var/mobile/Containers/Data/PluginKitPlugin/51C5E4F2-6F1F-4466-A428-73C73B9CC887/SystemData/com.apple.chrono/placeholders/cc_widget/systemMedium----360.00w--169.00h--23.00r--1f--0.00t-0.00l-0.00b0.00t.chrono-timeline ... Error Domain=NSCocoaErrorDomain Code=4 "file“systemMedium----360.00w--169.00h--23.00r--1f--0.00t-0.00l-0.00b0.00t.chrono-timeline”not exist。" UserInfo={NSFilePath=/private/var/mobile/Containers/Data/PluginKitPlugin/51C5E4F2-6F1F-4466-A428-73C73B9CC887/SystemData/com.apple.chrono/placeholders/cc_widget/systemMedium----360.00w--169.00h--23.00r--1f--0.00t-0.00l-0.00b0.00t.chrono-timeline, NSUnderlyingError=0xa693d3a80 {Error Domain=NSPOSIXErrorDomain Code=2 "No such file or directory"}}
Hello,
I just noticed weird unexpected behaviour.
It seems when you present UIAlertController or custom VC as partially screen covering formsheet, ALL the views underneath get 0.8 alpha tint (ios 15 and 18)
Is there any way to disable this behaviour?
So far it only breaks minor custom "star" view but I imagine arbitrarily adding 0.8 alpha to EVERYTHING can really mess up some layouts/designs.
Regards,
Martynas Stanaitis
Topic:
UI Frameworks
SubTopic:
UIKit
I have DNG files that I want to open and show as EDR content in my app. It seems like the DNG files should have enough per pixel information to show more colors that Display P3 but whenever I load the images using CIRawFilter and then inspect the outputImage color space it is always "DisplayP3", not something like "ITU-R BT.2100 PQ" there doesn't seem to be any way to make it load with a different color space for displaying EDR images.
Does this make sense for DNG files, it seems like it should?
If I open the same file using CIImage with the expandToHDR option e.g.
CIImage(contentsOf: rawURL, options: [.expandToHDR: true])
then it does have the desired EDR color space, but then I don't get any of the properties that are available via the CIRAWFilter class to manipulate the data.
Basically I just want to be able to open the DNG file via CIRAWFilter and then display it in my SwiftUI app as an EDR image by adding the allowedDynamicRange(.high) property.
Image("my-dng-image").allowedDynamicRange(.high)
Or do DNG files (just RAW not ProRAW) not contain enough information to be displayed as EDR images, seems like they should.
I was determined to fully rely on SwiftUI's navigation system giving the fact I'm starting a new project - strongly reconsidering this after a very basic requirement.
Namely: navigate between my two screens while wanting to hide the back button label.
One of them has a large navigation title
The other one has no navigation title
The problem is that back button icon simply jumps from top, a little bit down (where the title is supposed to be) and then back to top while navigating - resulting in a rough bouncy animation.
struct ParentView: View {
var body: some View {
NavigationStack {
WelcomeView()
.navigationDestination(for: WelcomeRoute.self) { route in
destinationView(for: route)
}
}
}
...
}
struct WelcomeView: View {
var body: some View {
ScrollView {
VStack {
...
NavigationLink(value: WelcomeRoute.Routes.next) {
Text("Next screen")
}
}
}
.navigationTitle("WELCOME")
.navigationBarTitleDisplayMode(.large)
}
}
struct NextWelcomeView: View {
var body: some View {
ScrollView {
VStack {
....
Text("Hello")
}
}
.toolbarRole(.editor)
}
}
Hi everyone,
I'm working on a tvOS app using SwiftUI, and I want to disable the focus effect (the default focus glow/bounce) on a specific Button. According to the documentation:
/// - Parameter disabled: A Boolean value that determines whether this view
/// can display focus effects.
/// - Returns: A view that controls whether focus effects can be displayed
/// in this view.
I used .focusEffectDisabled(true) on the Button, expecting the focus style to be completely disabled for that view. However, this doesn’t seem to have any effect in my tvOS 17+ app – the button still shows the default focus visual effect when focused.
Here’s a simplified example:
Button("Click Me") {
// action
}
.focusEffectDisabled(true)
This still shows the bounce/glow focus effect. Am I missing something, or is this a bug?
Has anyone managed to fully disable the focus effect for a view (especially Button) in tvOS using SwiftUI? Any workarounds or additional modifiers I should apply?
Thanks in advance!
We are looking at the possibility of launching our app through Siri with a locked device. We have the device responding to our App Intent but it is asking to be unlocked first. If the device is locked the intent works perfectly. It just doesn't seem to respect the set intentAuthenticationPolicy.
Thank you for you time looking into this.
We have set these var to .alwaysAllowed and open to true.
static var authenticationPolicy: IntentAuthenticationPolicy = .alwaysAllowed
static var openAppWhenRun: Bool = true
Here is our full test code:
import AppIntents
import SwiftUI
// MARK: - App Intents
struct OpenAppIntent: AppIntent {
static var title: LocalizedStringResource = "Open Main App"
static var description: IntentDescription? = .init(stringLiteral: "Opens the App")
static var authenticationPolicy: IntentAuthenticationPolicy = .alwaysAllowed
static var openAppWhenRun: Bool = true
func perform() async throws -> some IntentResult {
print("App opened")
return .result()
}
}
struct TestAppShortcutProvider: AppShortcutsProvider {
static var appShortcuts: [AppShortcut] {
AppShortcut(
intent: OpenAppIntent(),
phrases: [
"Begin \(.applicationName)"
],
shortTitle: "Open App",
systemImageName: "popcorn.fill"
)
}
}
Problem
Setting ".environment(.layoutDirection, .rightToLeft)" to a view programmatically won't make buttons in menu to show right to left.
However, setting ".environment(.locale, .init(identifier: "he-IL"))" to a view programmatically makes buttons in menu to show Hebrew strings correctly.
Development environment: Xcode 16.x, macOS 15.3.1
Target iOS: iOS 17 - iOS 18
The expected result is that the button in the menu should be displayed as an icon then a text from left to right.
Code to demonstrate the problem:
struct ContentView: View {
var body: some View {
VStack(alignment: .leading) {
Text("Buttons in menu don't respect the environment value of .layoutDirection")
.font(.subheadline)
.padding(.bottom, 48)
/// This button respects both "he-IL" of ".locale" and ".rightToLeft" of ".layoutDirection".
Button {
print("Button tapped")
} label: {
HStack {
Text("Send")
Image(systemName: "paperplane")
}
}
Menu {
/// This button respects "he-IL" of ".locale" but doesn't respect ".rightToLeft" of ".layoutDirection".
Button {
print("Button tapped")
} label: {
HStack {
Text("Send")
Image(systemName: "paperplane")
}
}
} label: {
Text("Menu")
}
}
.padding()
.environment(\.locale, .init(identifier: "he-IL"))
.environment(\.layoutDirection, .rightToLeft)
}
}
I want to record screen ,and than when I call the method stopCaptureWithHandler:(nullable void (^)(NSError *_Nullable error))handler to stop recording and saving file. before call it,I check the value record of RPScreenRecorder sharedRecorder ,the value is false , It's weird! The screen is currently being recorded !
I wonder if the value of [RPScreenRecorder sharedRecorder].record will affect the method stopCaptureWithHandler:
-(void)startCaptureScreen {
[[RPScreenRecorder sharedRecorder] startCaptureWithHandler:^(CMSampleBufferRef _Nonnull sampleBuffer, RPSampleBufferType bufferType, NSError * _Nullable error) {
//code
} completionHandler:^(NSError * _Nullable error) {
//code
}];
}
- (void)stopRecordingHandler {
if([[RPScreenRecorder sharedRecorder] isRecording]){
// deal error .sometime isRecording is false
}else {
[[RPScreenRecorder sharedRecorder] stopCaptureWithHandler:^(NSError * _Nullable error) {
}];
}
}
here are my code.