I have just installed Xcode and the simulator is not working correctly I get the following error
"Cannot preview in this file Unexpected error occurred"
Xcode Previews
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The SwiftUI previews have been working fine in Xcode 16.0 beta, but ever since I added Firebase into my app, I've been getting error with previews.
CrashReportError: IshaanCord crashed
IshaanCord crashed. Check ~/Library/Logs/DiagnosticReports for crash logs from your application.
Process: IshaanCord[5651]
Date/Time: 2024-07-04 19:29:51 +0000
Log File: <none>
"Cannot preview in this file"
Does anyone know how to fix this? Thank you.
Cannot select individual view in selectable mode in Xcode preview, it only show the whole blue device border.
I don't know why after I connected to firebase in my app my preview just started to crash. here are some screen shots
== PREVIEW UPDATE ERROR:
JITError
==================================
| NoBuiltTargetDescriptionCouldBeFound
|
| translationUnit: PreviewTranslationUnit(moduleNamePrefix: "Previews_EmptyFeedRow", sourceIdentifier: file:///Users/bryananderson/Developer/JournalApp/JournalApp/Interface/Feed/EmptyFeedRow.swift -> EmptyFeedRow.swift, parseTree: ParseTree(version: 727, statements: 3, providers: 1), update: nil, changesContextMemoizer: PreviewsPipeline.PreviewTranslationUnit.(unknown context at $34b4b9c4c).ChangesContextMemoizer(parseTree: ParseTree(version: 727, statements: 3, providers: 1), sourceIdentifier: file:///Users/bryananderson/Developer/JournalApp/JournalApp/Interface/Feed/EmptyFeedRow.swift -> EmptyFeedRow.swift, cachedValue: os.OSAllocatedUnfairLock<Swift.Optional<PreviewsModel.ParseTree.PreviewChangesContext>>(__lock: Swift.ManagedBuffer<Swift.Optional<PreviewsModel.ParseTree.PreviewChangesContext>, __C.os_unfair_lock_s>)), registryDeclarationMemoizer: PreviewsPipeline.PreviewTranslationUnit.(unknown context at $34b4b9bec).RegistryDeclarationMemoizer)
|
| builtTargetDescriptions:
|
== VERSION INFO:
Tools: 16A5171c
OS: 24A5264n
PID: 906
Model: MacBook Pro
Arch: arm64e
== ENVIRONMENT:
openFiles = [
/Users/bryananderson/Developer/JournalApp/JournalApp/Interface/Feed/EmptyFeedRow.swift
]
wantsNewBuildSystem = true
newBuildSystemAvailable = true
activeScheme = JournalApp
activeRunDestination = iPhone 15 Pro variant iphonesimulator arm64
workspaceArena = [x]
buildArena = [x]
buildableEntries = [
Remember.app
]
runMode = JIT Executor
== SELECTED RUN DESTINATION:
name = iPhone 15 Pro
eligible = true
sdk = Optional(<DVTSDK:0x13870da30:'iphonesimulator18.0':Simulator - iOS 18.0:<DVTFilePath:0x600001e8c700:'/Applications/Xcode-beta.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator18.0.sdk'>>)
variant = Optional("iphonesimulator")
device = Optional(<DVTiPhoneSimulator: 0x32f00d290> {
SimDevice: iPhone 15 Pro (CF3C85BC-F559-4437-9072-7F30153B399B, iOS 18.0, Booted)
PairedSim: <DVTiPhoneSimulator: 0x33733d150> {
SimDevice: Apple Watch Series 9 (45mm) (627CE93E-EB02-4200-BE40-3DCB5C91DB44, watchOS 11.0, Shutdown)
}
})
== SELECTED RUN DESTINATION:
Simulator - iOS 18.0 | iphonesimulator | arm64 | iPhone 15 Pro | Apple Watch Series 9 (45mm)
jit enabled: true
fallback to dynamic replacement: false
Crowdstrike Falcon vs Xcode performance
Our IT department is using CrowdStrike Falcon, an ML-security tool, on all the Mac hardware. It will flag processes as malicious, and it sounds like it may sandbox such processes that are deemed malicious and / or scan anything the process touches.
TLDR
Does anybody know how to make CrowdStrike Falcon behave nicely with Xcode and its tools and prevent it from consuming high CPU and interfering with the build and debugging processes? Xcode, SwiftUI previews and building should be as performant as possible.
Details
Perplexity describes CrowdStrike Falcon as follows:
CrowdStrike Falcon is a cloud-based endpoint security platform that provides real-time protection against malware, ransomware, and other cyber threats. It uses artificial intelligence and machine learning to detect and prevent known and unknown threats across endpoints (laptops, desktops, servers, etc.), cloud workloads, and cloud environments. The Falcon platform includes next-generation antivirus, endpoint detection and response (EDR), managed threat hunting, vulnerability management, and other security capabilities delivered through a lightweight sensor that streams data to the CrowdStrike cloud for analysis and response.
The problem is that apparently Falcon's ML signatures will flag Xcode as malicious. So when building in Xcode, Falcon will use a huge amount of CPU (I have seen it go up to 456%), affecting build performance. I am getting the impression it is sandboxing and / or scanning every single file Xcode touches. The same goes for the iOS Simulator which will also cause Falcon to consume lots of CPU. It's clear this is affecting our build performance a lot.
Falcon supports a number of exclusions:
Machine learning (ML) exclusion: For trusted file paths, stop all ML-based detections and preventions, or stop files from being uploaded to the CrowdStrike cloud.
Indicator of attack (IOA) exclusion: Stop all behavioral detections and preventions for an IOA that’s based on a CrowdStrike-generated detection.
Sensor visibility exclusion: For trusted file paths that you want to exclude from sensor monitoring, minimize sensor event collection, and stop all associated detections and preventions. Use sensor visibility exclusions with extreme caution. Potential attacks and malware associated with excluded files will not be recorded, detected, or prevented.
Using Sensor Visibility Exclusions it is possible to exclude applications on file pattern basis and preventing Falcon's ML signatures for flagging any such process as malicious. Which means that it is possible to exclude /Applications/Xcode.app/** and prevent it, or the processes it spawns, as malicious.
However, Xcode and the toolchain are much more complicated than just excluding a single binary. Switching toolchains via sudo xcode-select -s will also update a lot of files in /usr (see Xcode.app/Contents/Developer/usr) such as /usr/bin/swift*, /usr/bin/ibtool*, /usr/bin/lldb and /usr/bin/xcrun (there are many more).
For testing Xcode performance we excluded /Applications/Xcode.app/** and /usr/bin from Falcon, but just launching the simulator and a simulator build of the app will still cause Falcon to go up to about 300%. I assume this will affect SwiftUI live previews as well. Probably /Users/*/Library/Developer/** should be excluded as well then?
Obviously, Falcon's AI/ML should just identify all of this as legitimate software development tools and no exclusions should be necessary...
IMHO a file-pattern based exclusion seems to contradict what this tool is supposed to do. I would think it should evaluate signing (codesign / spctl) or validate checksums, rather than file pattern based exclusions. But as long as Xcode becomes more performant I am not complaining. The less an IT tool is flagging legitimate software as malicious and interfering with our daily work, the better.
So my question is if anybody knows how to make CrowdStrike Falcon behave nicely with Xcode and its tools and prevent it from consuming high CPU and interfering with the build and debugging processes? Xcode, SwiftUI previews and building should be as performant as possible.
I have a project with two local packages
One client package with an interface and some models with dynamic type in the Package.Swift
One feature package with the UI and a dependency to the client package
When I try to preview a view that is not using any models or code from the client package, it loads just fine e.g. a view that is just a container to display things like a card
But when I tried to preview any other view that actually uses models from the client package, it just fails
the first few lines of the preview error display
LinkDylibError: Failed to build <filename>.swift
Linking failed: linker command failed with exit code 1 (use -v to see invocation)
ld: warning: search path '/Applications/Xcode-15.4.0.app/Contents/SharedFrameworks-iphonesimulator' not found
Undefined symbols for architecture arm64:
Also, I'm using Xcode 15.4 and iOS 17 as the min version
In the first Xcode 16 beta, none of my SwiftUI previews work - they all just crash on start up.
Has anybody run into this and found a workaround? Have tried all the usual steps of cleaning the project/restarting Xcode.
SwiftUI preview hangs on "Preparing iPhone Simulator for Previews". Also simulator hangs when trying to build and run. This occurred after I installed iOS 17 simulator. I tried reverting back to an iOS 16 version of the simulator, but haven't figured out how to do that. Build and run to an iPhone device works fine. Any ideas would be appreciated. Thanks.
Hiya,
I am having issues trying to use previews in the xcode 15 beta, i am using an M2 macbook air with 8gb of ram.
I am using MacOS Sonoma and iOS 17.0 Beta 1 and am struggling using previews, the base simulator works but no previews.
I am not receiving any error so am very confused.
Any help would be majorly appreciated.
Thanks,
Gus
Greetings...
I am trying to use @Namespace for my matchedGeometryEffect use case.
prior to Xcode 15 beta the following code worked just fine:
struct ChapterItem_Previews: PreviewProvider {
@Namespace static var namespace
static var previews: some View {
ChapterItem(namespace: namespace, show: .constant(true))
}
}
However trying to do the same within the new Xcode 15 beta #Preview Macro
#Preview {
@Namespace var namespace
ChapterItem(namespace: namespace, show: .constant(true))
}
produces the following error message:
Ambiguous use of 'Preview(_:traits:body:)'
May I kindly get assistance on the proper way I can get this to work in Xcode 15 beta?
Please be as detail as you can since I'm still new to swiftUI as well Thank You.
Topic:
Developer Tools & Services
SubTopic:
Xcode
Tags:
Xcode
Xcode Previews
wwdc2023-10252
wwdc2023-10165
Is there any way to stop previews from live updating? It's constantly running and that's nice when I'm developing, but I'd like it to pause updating when I'm not using the Xcode. It heats up my m1 air and drains unnecessary power reducing the battery levels significantly.
The Build for Previews builds all my targets including the test targets. Is there a way to configure the relevant targets? I do not see an option in the schema editor, and disabling Find Implicit Dependencies has no effect either.