I have this error going on in Xcode:
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFString _isDecompressing]: unrecognized selector sent to instance 0x71863b0'
When you have
unrecognized selector send to instance error, you have to check if you declared and implemented the method that is pointed out by the error, in your case
_isDecompressing. If everything is ok on your class (the method is declared and implemented) then have a look at the class type that is calling the method, in your case
NSString most of the time the class is wrong.
So in order to point out your problem, you are trying to call a method
NSString which doesn't exist. So make sure every object that calls this method is of your desired type and not
A good way to find the line that is causing the crash is to enable exceptions breackpoints.