Just another heads-up: noticed that native OK/Cancel boxes cause JUCE apps built on iOS SDK 6.1.3 to crash on iOS 7.
Note: OK boxes are fine
I'm seeing this as well, only it seems to be happening here regardless of what buttons the message box is showing. It happens whether or not a Component is passed to showMessageBox(). I get the following in the debug output when the app crashes:
2013-11-04 17:31:59.722 MyApp[1270:60b] -[__NSArrayI alertView:clickedButtonAtIndex:]: unrecognized selector sent to instance 0x15fdf260
2013-11-04 17:32:00.816 MyApp[1270:60b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSArrayI alertView:clickedButtonAtIndex:]: unrecognized selector sent to instance 0x15fdf260'
*** First throw call stack:
(0x30077f4b 0x3a7e66af 0x3007b8e7 0x3007a1cb 0x2ffc94d8 0x32a02dcd 0x32a02ca7 0x329078bb 0x329baf7b 0x3286afb9 0x327e31f3 0x300431cd 0x30040b71 0x30040eb3 0x2ffabc27 0x2ffaba0b 0x34c9f283 0x3284f049 0x2cc2c7 0x2cc231 0xbcdbf 0x3aceeab7)
libc++abi.dylib: terminating with uncaught exception of type NSException
I couldn't get this to happen in the simulator, but I did add a missing prototype to one of the obj-C classes involved. No idea if that'd help, but you might want to give it a try.