NSCFDictionary setObject:forKey in xcode
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I have a problem in my code the app is crash with error
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFDictionary setObject:forKey:]: attempt to insert nil value (key: app_ver)'
*** First throw call stack:
(0x874022 0x257acd6 0x81ca48 0x81c9b9 0x8732da 0x8c473 0x8c119 0x7d803 0x7d74c 0x875e42 0x82670 0x13eda49 0x13ebe84 0x13ecea7 0x13ebe3f 0x13ebfc5 0x1330f5a 0x2f1ca39 0x2fe9596 0x2f13120 0x2fe9117 0x2f12fbf 0x84894f 0x7abb43 0x7ab424 0x7aad84 0x7aac9b 0x133040f 0x82a35 0x12fc4d6 0x12fc447 0x99595ed9 0x995996de)
terminate called throwing an exception
