Eu tenho um problema com o Xcode 11 em execução na Catalina (ele tinha o mesmo problema com o Moave). Quando tento copiar / colar uma exibição ou um ViewController de um storyboard para outro, o Xcode falha com esta exceção:
...
Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Exception Note: EXC_CORPSE_NOTIFY
Application Specific Information:
Sending paste: to IBStructureAreaDockView from <NSMenuItem: 0x7fe24030ddd0 Paste>
ProductBuildVersion: 11A1027
ASSERTION FAILURE in /Library/Caches/com.apple.xbs/Sources/IDEInterfaceBuilder/IDEInterfaceBuilder-15400/InterfaceBuilderKit/WidgetIntegration/View/IBViewIntegration.m:2451
Details: There should only be 1 parent of all the constraint items extracted from the pasteboard: {(
)}
Object: <IBUIView: 0x7fe23db1c600>
Method: -ibDidExtractObjects:fromPasteboard:intoDocument:context:
Thread: <NSThread: 0x7fe23ac17e80>{number = 1, name = main}
Hints:
0: Sending paste: to IBStructureAreaDockView from <NSMenuItem: 0x7fe24030ddd0 Paste>
Backtrace:
0 -[IDEAssertionHandler handleFailureInMethod:object:fileName:lineNumber:assertionSignature:messageFormat:arguments:] (in IDEKit)
1 _DVTAssertionHandler (in DVTFoundation)
2 _DVTAssertionFailureHandler (in DVTFoundation)
3 -[NSView(IBViewIntegration) ibDidExtractObjects:fromPasteboard:intoDocument:context:] (in IDEInterfaceBuilderKit)
4 -[IBUIView(IBUIViewIntegration) ibDidExtractObjects:fromPasteboard:intoDocument:context:] (in IDEInterfaceBuilderCocoaTouchIntegration)
5 -[IBDocument ibDidExtractObjects:fromPasteboard:context:] (in IDEInterfaceBuilderKit)
6 -[IBDocument insertObjectsFromPasteboard:ofType:asChildrenOfObject:atIndex:context:finishExtractingObjectsBlock:] (in IDEInterfaceBuilderKit)
7 -[IBDocument insertOrMoveChildrenFromPasteboard:ofType:asChildrenOfObject:atIndex:context:finishExtractingObjectsBlock:] (in IDEInterfaceBuilderKit)
8 -[IBDocument addOrMoveChildrenFromPasteboard:ofType:toObject:context:finishExtractingObjectsBlock:] (in IDEInterfaceBuilderKit)
9 -[IBStoryboardDocument addOrMoveChildrenFromPasteboard:ofType:toSceneGroup:context:] (in IDEInterfaceBuilderKit)
10 -[IBSceneDockViewController performDockPasteWithPasteboard:context:] (in IDEInterfaceBuilderKit)
11 -[IBSceneDockViewController dockViewPerformPaste:] (in IDEInterfaceBuilderKit)
12 -[IBStructureAreaDockView paste:] (in IDEInterfaceBuilderKit)
13 -[NSApplication(NSResponder) sendAction:to:from:] (in AppKit)
14 __37-[DVTApplication sendAction:to:from:]_block_invoke.86 (in DVTKit)
15 DVTInvokeWithFailureHint (in DVTFoundation)
16 -[DVTApplication sendAction:to:from:] (in DVTKit)
17 -[NSMenuItem _corePerformAction] (in AppKit)
18 -[NSCarbonMenuImpl performActionWithHighlightingForItemAtIndex:] (in AppKit)
19 -[NSMenu performKeyEquivalent:] (in AppKit)
20 routeKeyEquivalent (in AppKit)
21 -[NSApplication(NSEvent) sendEvent:] (in AppKit)
22 -[IDEApplication sendEvent:] (in IDEKit)
23 -[NSApplication run] (in AppKit)
24 NSApplicationMain (in AppKit)
25 main (in Xcode)
26 start (in libdyld.dylib)
Performing @selector(paste:) from sender NSMenuItem 0x7fe24030ddd0
abort() called
Application Specific Signatures:
[parentsOfItemsInConstraints count] == 1
...
Está acontecendo com outra pessoa? Isso não é suportado pelo storyboard?
cmd + D
funciona se o que você deseja é duplicar um único viewController no mesmo Storyboard, mas o que eu preciso é copiar e colar em um Storyboard diferente.