'"Cannot Preview in this file - Failed to launch [App Name]"

I am trying to play around with swiftUI in Xcode 11 and macOS Catalina. BUT After creating a new Project, there is a boiler plate code with a Text that says hello World. I want to have a live preview of this simple welcome message in the canvas by the side of the code.

When i hit the resume button : It says :

Cannot Preview in this file - Failed to launch [App Name]

I've tried hitting the diagnostic button that generated a report to send it to APPLE saying:

[FailedToLaunchError(url: file:///Users/naive/Library/Developer/Xcode/DerivedData/first_swiftUI-dymizjogcbtouhclgjhhefagmcqo/Build/Intermediates.noindex/Previews/first_swiftUI/Products/Debug-iphoneos/first_swiftUI.app, underlying: Error Domain=NSOSStatusErrorDomain Code=-10661 "(null)" UserInfo={_LSLine=3554, _LSFunction=_LSOpenStuffCallLocal}, failureCategory: UVFoundation.FailureCategory.infrastructureFailure) ]

Here's the code, It is the default code that comes with new project created with Xcode 11 and SwiftUI option checked:

import SwiftUI

struct ContentView : View {
    var body: some View {
        Text("Hello World")
    }
}

#if DEBUG
struct ContentView_Previews : PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}
#endif

I expect the canvas to show up and display live preview of my code. The canvas is not showing up !!

There are two warning messages generated :

:0: warning: imported declaration 'UITableViewDiffableDataSourceCellProvider' could not be mapped to 'UITableViewDiffableDataSourceReference.CellProvider'

:0: warning: imported declaration 'UICollectionViewDiffableDataSourceCellProvider' could not be mapped to 'UICollectionViewDiffableDataSourceReference.CellProvider'

other than that, My iPad 11"with iPadOS beta runs the app, The simulator is working as well

Solution 1:^[1]

I encountered this UVFoundation.FailureCategory.infrastructureFailure when starting an iOS app with SwiftUI and then checking the Mac target in the project properties (i.e., using Catalyst to create a cross-platform app). When I did this the default device changed to "My Mac" and preview stopped working, yielding this error in the diagnostic window.

Preview for the Mac target doesn't seem to be supported—you have to select some iOS target ("Generic iOS Device" works just fine for me). Tested on Mojave beta 5 with Xcode 11 beta 5. From the Xcode 11 beta 5 release notes: "Xcode 11 doesn’t support working with SwiftUI in a Mac Catalyst app. (41416222, 51201699)"

"My Mac" selected, it doesn't work!

Working with "Generic iOS device" selected.

Solution 2:^[2]

I got it fixed by assigning command line tools to Xcode 11, it was set to previous version of Xcode 10.

Go to : Preferences > location > commandLine tools [drop down] > select Xcode 11

Solution 3:^[3]

Check Diagnostic reports on path ~/Library/Logs/DiagnosticReports.
Open fileName.crash file (fileName is the file which causing crash) and search Application Specific Information
Fix your code as per the information

Solution 4:^[4]

I just quit and reopened Xcode with the same project and the preview started working again.

If that doesn't work try Command + K to clean the project, then tap "Resume" to try again.

Solution 5:^[5]

I had this issue (Cannot preview in this file -- Update failed) on Catalina 10.15.5 with Xcode 11.5 when trying to preview a Canvas for MacOS target with a vanilla SwiftUI project template after applying cocoapods and Xcode suggestions.

None of the already listed solutions worked for me.

I got a hint in the "Diagnostics" saying "... code signature in (.../Data/ContentView.2.preview-thunk.dylib) not valid for use in process using Library Validation: mapped file has no Team ID and is not a platform binary (signed with custom identity or adhoc?))} ..."

This solved the issue: Project > TARGETS > MacOSTarget > Signing Certificate > Development

(Previously was "Sign to Run locally")

Solution 6:^[6]

If you click on your project name to the right of the run/ 'play' button you can switch over to the iOS options. It is initially set to macOS.

Solution 7:^[7]

I had the same problem and changing the location was what worked for me. I changed it from "Relative to Group" to "Relative to Project" and the preview came up!

In this link, you can find more information

Solution 8:^[8]

Open Terminal and type the following command

sudo xcode-select -s /Applications/Xcode-beta.app/Contents/Developer

and then run sudo xcodebuild -license. Type agree and hit return key to the license. Also select Xcode 11 for Command Line tools from Preference -> Location -> CommandLine in Xcode. This worked for me.

Solution 9:^[9]

In my case, I checked generated Diagnostics report and it showed

" Dyld Error Message: app was built for iOS 13.2 which is newer than this simulator 13.1 "

So I changes the iOS Deployment target to 13.1 from build settings.

Tap on resume and it worked for me.

Solution 10:^[10]

For me pick anything but the 11 Pro max and it will work.

Solution 11:^[11]

For my case it was because I unintentionally tried to build on real device instead of the simulator. By selecting a simulator from the list, it got up and running again.

Solution 12:^[12]

I had the same problem and I found it was a runtime error that was causing this error because the project was compiling successfully. The error was caused by an image that was not referenced within the project.

Solution 13:^[13]

Same error

Try to:

Editor > Canvas > Refresh rate

Solution 14:^[14]

None of the above worked for me - but I did find a way...

Copy the content of the offending file (eg ContentView.swift).
Delete the offending file from your project.
Create a new 'SwiftUI View' and rename it back to whatever file you deleted.
Paste the content you copied in step 1 back in.
Click resume in the canvas.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution	Source
Solution 1
Solution 2	shim
Solution 3	Kishore Suthar
Solution 4	shim
Solution 5	shim
Solution 6	Dharman
Solution 7	Juanes30
Solution 8	Vinoth Vino
Solution 9	chitra
Solution 10	Jevon Charles
Solution 11	Malloc
Solution 12	pableiros
Solution 13	Alessandro Dovere
Solution 14	Leo

'"Cannot Preview in this file - Failed to launch [App Name]"

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