Interface Builder XIB Compiler error

Question

I get this error message when connecting two UISwipeGestureRecognizers to a single view in my project inside of a XIB file (though not in a new project, curiously). Anybody know what this error means? It is a compile error, not a runtime error. I'm using Xcode 4.4 (this error doesn't happen on Xcode 4.5 actually). This is an error from inside interface builder.

Assertion failure in -[IBCocoaTouchToolObjectPackage connectionsByProcessingConnections:], /SourceCache/IBSimulatorComponents/IBSimulatorComponents-223/IBCocoaTouchTool/IBCocoaTouchToolObjectPackage.m:1132012-08-03 16:52:01.428 Interface Builder Cocoa Touch Tool[5646:11903] Exception producing nib: Mismatched addsContentToExistingCollection value for the coalescing outlet connection & one of its fragments.

Entresol

Answer 1

I suspect this occurs because Interface Builder allows your outlets to get into an inconsistent state. It's a logic bug in Interface Builder that manifests as a run-time exception in the ibtool compiler. I was able to work around it by disconnecting the outlets and outlet collections I had recently created, and then rewiring them.

Karb

Interestingly enough, I also saw this error immediately after wiring up two UISwipeGestureRecognizers, though I can hardly see how such an error would be specifically caused by that class. – Karb

Unfortunately for me, unwiring and rewiring them just causes the error again. I will try disconnecting all the connections and rewiring them when I get back to the project. – Entresol

Well, randomly disconnecting and reconnecting some of the connections made it work...so I guess this is the correct answer lol. – Entresol

Yeah, it's a pity that we sometimes have to apply voodoo to get our tools working, but that's the state of things on the Xcode front... – Karb

Just had this problem. Random unwiring and rewiring is the solution. My preferred solution is to not use IB, but alas, other people's code. – Textile

Answer 2

I was actually able to get rid of the error by deleting the entire Panel in the XIB, and then just undoing the delete. Clean + Build and the error was gone. Not sure if that will work for others as well.

Shirelyshirey