When I try to preview one of my views in the canvas I keep getting the following error:
PreviewUpdateTimedOutError: Updating took more than 5 seconds
All my other views load perfectly fine.
Why is this happening and how do I resolve?
I am using SwiftUI in Xcode 11.4 (public release)
I stopped using the simulator and chose "Any iOS Device" and that solved the problem.
In my case the issue was this line in Build settings:
Something I did accidentally changed signing settings in my project. Specifically, "signing identity" was set to "Sign to Run Locally.".
For some reasons, SwiftUI Previews don't work then.
Simply deleting this line from build settings (aka setting default value) solved the problem.
Some time, the error displaying is not the real error.
For me it was because i missing : .environmentObject(...)
As of Xcode 12.5.1, the message PreviewUpdateTimedOutError: Updating took more than 5 seconds most likely means that your app crashed and thus updating the preview failed. The real reason for the crash is unfortunately obscured by this useless message (why Apple would do that is beyond me). To get at the real reason, you'll need to:
click Diagnostics at the top of the preview next to the useless error message
in the next dialog, click Generate Report > Reveal in Finder
This will take a bit. Then Finder will open with a folder highlighted. Open that folder. Inside you'll see a lot of log files and folders.
If your app indeed crashed, you'll see a folder called CrashLogs which contains crash logs for your app, including the error message and stack trace. This should help you resolve the actual error causing the preview to break.
Note that for me, sometimes the CrashLogs were not included in the report even though my app really did crash. Retrying the preview and generating another report fixed this for me. The whole error reporting process seems to be rather unstable for the previews, unfortunately.
Try Clean (Shift + ⌘ + K) and Build (⌘ + B) to build again the SwiftUI project, it works in Xcode 11.6. Try building a basic hello world app.
In my case the issue was that the PreviewProvider was marked private. Simply make it internal or remove the private access modifier.
private /* <- remove */ struct YourView_Previews: PreviewProvider {
static var previews: some View {
// Your previews
}
}
I am using Version 13.2.1 (13C100). I have Clean (Shift + ⌘ + K) and Build (⌘ + B) the project. But, the problem remains.
Then, just restarted Xcode. And the problem gone.
In my case viewModel required to display SwiftUI_preview was doing a call to a CoreData (fast call) in the init of the viewModel.
Moved actual call of that "reload() method" so it's not called on preview, fixed.
(I believe the correct way is to use mocked protocol instead of instance of the viewModel)
If you have an .onAppear clause, try commenting that out for preview.
None of these suggestions helped me but I did discover that you can't rely entirely on a successful build to pick up all issues. In my case I had '.modifier(modifier:)' entered incorrectly as 'modifier(modifier:)'. My code built successfully but my preview did not work until I added the period before modifier.
For me the issue was related to a force unwrapping of an element not being found at preview time.
Note: Always check the diagnostics report. The issue will be at the top section after termination reason.
In my case the canvas/screen size was smaller than the content, so simply wrapping my content in the scrollView do remove the error and displaying the content in the canvas.
I had a fatalError("...") in my code, which I only figured out after reading the diagnostic logs. Would be nice if SwiftUI actually hinted this!
You can get the diagnostics by clicking "Diagnostics" next to "Try Again" at the top of the preview window.
To summarise lots of answers here, it seems that the preview taking a while to update is the equivalent of a crash, when running on a real device or on the simulator.
First comment out all the environment Objects are used for the particular View. Once you get preview then uncomment it to run the build. This trick works for me
//#EnvironmentObject var observerObj:PropertyObserver
I had this issue as well, and nothing fixed the problem. I am now on 11.6 and after updating the issue went away. I think it might be a problem with Xcode 11.4.
I'd suggest updating Xcode if possible.
In SwiftUI, you couldn't add more than 10 subviews into your contentview, otherwise it couldn't compile.
I had the same problem, then I started to comment out the subViews inside my main view, one by one & try to preview again then I found out the problem was caused because I forgot to put a dot before one of the subViews attributes.
So that's how I fixed it.
The reason is because its unable to find the landmarkData.json file. To resolve this,
select landmark.json file in Resources.
Show Inspectors ( top right icon )
Select show file inspector
Under Target membership, select / check Landmarks
This should resolve the preview issue.
For some reason, in SwiftUI, when I embeded Text in Scroll View and VStack, this error occurred. After few unsuccessful attempts to fix this by clearing and building project, I deleted code and wrote it down again, same as it was. Now it is working.
I had my run device set to a real device I use for testing. When I changed that to one in the simulator it started working again.
Similar to #YannSteph, this happened to me because I put the .environmentObject() at the app entry point where it creates the first view:
#main
struct RecipeApp: App {
var body: some Scene {
WindowGroup {
RecipeTabView()
.environmentObject(RecipeModel())
}
}
}
But this prevented the preview from working. I thought I was being smart putting it there, so all the views could have access to it, but it just crashed the preview.
Moving it back into the main View.Swift file that is my app's starting view fixed the preview issue.
^^^
EDIT: Ran into this again when I didn't put the .environmentObject() in the struct for the preview. Probably a rookie mistake but there appears to be many ways to trigger this error.
I had the same issue after creating a brand new Multiplatform App project using Xcode 12.5. Based on the solutions above I followed a hunch and now believe that the issue is due to invalid path parameters.
After renaming the Schemes and Targets from (iOS) to .iOS (and the same for macOS), to remove spaces and brackets, it is now working.
I had this issue after changing bundle id and signing from personal to team.
After changing device to Any device as advised here, I received another error description, saying
Could not install the preview host "AppName.app" on iPhone 12 Pro Max
agentBundle = com.bundle.Its.AppName {
url: file:///Users/macbookair/Library/Developer/Xcode/DerivedData/AppName-> desupjbpqvjlegfbskxydixpouvc/Build/Intermediates.noindex/Previews/AppName/Prod> ucts/Debug-iphonesimulator/AppName.app
> version: 49557
signingInformation: Code Signing {
identifier: com.bundle.AppName
hasGetTaskAllow: false
isSandboxed: false
}
}
Clean build, deleting Derived, Deleting all apps installed on simulators, cleaning Xcode Cache, restarting Xcode and Mac didn't help.
What had helped was creating new project with initially correct bundle id and copying all my files there.
I have got into the same issue on Xcode 12.4, but the code works fine on Xcode 13.0.
I was following the IOS App Dev Tutorial, where one creates an app named ScrumDinger. I ran into this issue at Displaying Data in List
In my case the problem was that I wrote in CardView.swift
HStack {
Label("\(scrum.attendees.count)", systemImage: "person.3")
accessibilityLabel("\(scrum.attendees.count) attendees")
instead of
HStack {
Label("\(scrum.attendees.count)", systemImage: "person.3")
.accessibilityLabel("\(scrum.attendees.count) attendees")
The missing dot before accessibilityLabel was the problem.
Tutorial:
https://developer.apple.com/tutorials/app-dev-training/displaying-data-in-a-list
In my case the issue was that I was trying to preview a view with a fixed width (.previewLayout(.fixed(width: 344, height: 220))) wider than the selected simulator (iPhone SE 1st generation) 😬
I get this error often. My last time of occurrence, I had "gesture" instead of ".gesture". Usually its best to just need to find the error in your code yourself because Xcode does not point out the issue directly.
I only had Xcode 14 Beta installed on my machine and the previews did not work. All of the other answers did not work for me.
Installing Xcode 13.4.1 and running the preview with it did solve my problems and now I can also see the preview in Xcode 14 Beta as well.
In my case, I disabled automatic canvas refresh by going to Editor -> Canvas -> Automatically Refresh Canvas and making sure it.
Then I use ⌥⌘P (Command-Option-P) to refresh the canvas preview.
Since updating to Xcode 8 (at least I think this is what started it) my console has been filling up with all sorts of network activity stuff like:
I have no interest in seeing all that, how do I stop this?
Thanks in advance!
For the meantime, simply Edit Scheme -> Run -> Arguments ->Environment Variables -> Click + to add a new one -> Name: OS_ACTIVITY_MODE -> Value: disable.
There is a PR open to fix this too: https://github.com/facebook/react-native/pull/10065
NSLog will be suppressed but if you need to log in the native side you can use the logging functions inside RCTLog.h, which will still work.
This logging is caused by the iOS 10 SDK included in Xcode 8. There is a workaround:
https://twitter.com/rustyshelf/status/775505191160328194
However, be aware that this hides NSLog output on device.
iOS 10 / Xcode 8 GM build getting the below, never had it before on Xcode 7. Any ideas?
objc[25161]: Class PLBuildVersion is implemented in both
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/System/Library/PrivateFrameworks/AssetsLibraryServices.framework/AssetsLibraryServices
(0x12049a910) and
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/System/Library/PrivateFrameworks/PhotoLibraryServices.framework/PhotoLibraryServices
(0x1202c4210). One of the two will be used. Which one is undefined.
(NOTE: Only seems to happen in simulator, does not appear on real device).
Main Idea
Main idea is simple:
If your app (or dependencies, such as Pods) uses framework, that uses explicit (or implicit) PhotoLibraryServices.framework or AssetsLibraryServices.framework as dependency, Xcode warns you (even if you are using only one of them). It might be Photos/PhotosUI.framework or AssetsLibrary.framework, or another (I don't have full list of dependencies, but it is possible).
What is the problem?
Class with name PLBuildVersion is defined in both PhotoLibraryServices.framework and AssetsLibraryServices.framework. Class name is unique in Objective-C (you can't define 2 classes with same name), so it is undefined which one will be used in runtime.
However, I think that it will not be a problem, because both classes have same methods and fields (checked this with disassembler) and I guess that both were compiled from the same source.
Radar is already sent.
As per answer from Apple employee on Apple's Developer Forum:
You don't control either of the class sources listed, so there isn't anything you can or should do – aside from Reporting a Bug.
I was unable to find a way to get rid of the warning, but if you want to prevent the app from crashing, you need to provide a description for why you are accessing the camera, photo library, etc. This is new in iOS10.
Input the following into your Info.plist file.
Photo
Key: Privacy - Photo Library Usage Description
Value: $(PRODUCT_NAME) photo use
Camera
Key: Privacy - Camera Usage Description
Value: $(PRODUCT_NAME) camera use
More info can be found here: https://iosdevcenters.blogspot.com/2016/09/infoplist-privacy-settings-in-ios-10.html
I find you can get this error merely by using a UIWebView. My solution was to replace my use of UIWebView with WKWebView.
I had this after adding Answers on Fabric to my project.
Deleting derived data did the trick for me. (shift alt command k in XCode)
Edit a year later:
After deleting derived data, always exit XCode and start it again.
In unrelated cases I have the impression that deleting derived data does not clear XCode’s in memory caches of the derived data.
Resetting the iOS simulator fixed this for me. Simulator -> Reset Content And Settings.
In my case this warning started to appear after opening a second xcode project and running the second app on the simulator. After changing back to the first app, the warning started to appear. I just quit the Simulator and Xcode and reopened my project. The warning disappeared after that. If that doesn't solve it, proceed with the other answers. Xcode can be really picky sometimes.
I installed Xcode 6.0 beta and downloaded the iOS8 library Documentation.
but when i create a Swift project, try to typing code
func aa(){
let format = NSDateFormatter()
var pageData = format.
}
I find Xcode can't dot any property and function. Am I missing any step?
The problem is sloved, typing a whitespace can aid code completion
It's append when you change the hardware type and you choose less than iphone5.
Choose Iphone 6 for example in the list at the right of the stop button and the code completion for 'format' will appear.
I met the same problem and solve it by removing the non-ASCII char in comment (in my problem, it's a chinese char "年" automatically generated in comment by xcode).
btw. "typing a whitespace can aid code completion" doesn't work for me
It’s a bug, your code works on my system (OS X 10.9). Note that when typing code, I sometimes see the code completion crash for two seconds and come back.
When trying a first project named "swift", code completion crashed in a infinite loop… beta bugs… I just had to name it something else to test the language.
You know, I've experienced something similar with Objective C projects in Xcode 6 Beta 1. It seems Apple have changed the default behaviour a bit:
In Xcode 5.x code would always automatically complete as you type, but in this early beta try pressing ESCAPE - that will bring up the list you're looking for. Works for me. Some code auto completes as you type (both in Swift and Objective C), but at times only ESCAPE will bring up what we're looking for.
I'm nor sure if this is expected behaviour or a bug (I'm guessing the latter).
I must admit that your code works fine on my system without this trick. Just make sure you have code completion setup under Xcode - Preferences - Text Editing:
I am trying to develop QRCode reader application in iPhone.
I am trying to use ZXing SDK. i have successfully run the sample application given by ZXing. But i ma trying to develope new application as per instructions in Readme given by Zxing. but when i am trying to add ZxingWidget in build phases. it going add but it shows like below
I think it will getting problem to me. When i am trying to run application it will give erros like Lexical or Prepocessor issue File not found.
Is am doing any thing wrong when am added to files to application.
Actaully first of all i added ZxingWidget.xcodeproj to my application by drag and drop. But it wont give any alert window would you like copy like similar when we adding images or files to xcode. and next i added cpp and iphone folders to xcode application. and later i added the frameworks as per read me.
Please any one help me in this issue.
Thanks in advance
Pretty hard to help without the real error message. In the Issue Navigator, you can Right Click > Reveal in Log to see the complete error that you can copy and paste.
That said, it sounds a bit like it can't find the headers (though I'm just guessing without the real error message.) If so, double check steps 4 and 5 of the readme.
if you run on real device, the problem will be solved.
I don't know the reason.
But I guess It's related to Build Products Path.