invalid mode 'kCFRunLoopCommonMo

invalid mode 'kCFRunLoopCommonModes' provided to CFRunLoopRunSpecific - break on _CFRunLoopError_RunCalledWithInvalidMode to debug. This message will only appear once per execution

解决办法请看一下xib中是否正确选择了target

其他原因导致请参考：
http://www.jianshu.com/p/b54065e90e13
http://www.jianshu.com/p/a73f22d1c802