我正在 Xcode (4.4.1) 上构建一个 iOS (5.1) 应用程序，我几乎完成了第一阶段的开发，但我被困在最后一行代码上。我一直在使用 Kumulos 作为后端和 API 解决方案，目前所有 API 都运行良好，除了这一点：
Kumulos* k = [[Kumulos alloc]init];
[k setDelegate:self];
[k createNewTimePointWithJourneyIDFK:[journeyID integerValue]
andTime:currentDate andLat:[lat floatValue] andLon:[lon floatValue]];
当它遇到 createNewTimePointWithJourneyIDFK: 方法时，它会终止。在日志中它提到了这个方法，并说一个无法识别的选择器被发送到一个实例。
现在我意识到这个问题已经在 SO 上被问了一百万次，但我已经 1）检查了该方法是否已定义，以及 2）它是否已正确调用（或至少据我所知）。我完成上述的方式就是我完成其余 API 调用的方式，它们运行良好，所以我看不出问题出在哪里。非常令人沮丧，我在最后一行花了几个小时！所以请不要以为我在几分钟不知道该怎么做之后就听到了。
错误信息
2012-08-11 22:36:58.769 busApp4Kumulos[5485:707] -[Kumulos
createNewTimePointWithJourneyIDFK:andTime:andLat:andLon:]:
unrecognizedselector sent to instance 0x3d1b70 2012-08-11 22:36:58.778
busApp4Kumulos[5485:707]
*** Terminating app due to uncaught exception
'NSInvalidArgumentException', reason: '-[Kumulos
createNewTimePointWithJourneyIDFK:andTime:andLat:andLon:]:
unrecognized selector sent to instance 0x3d1b70'
*** First throw call stack:
(0x35add88f 0x37e84259 0x35ae0a9b 0x35adf915 0x35a3a650 0x3ef5
0x37f86de3 0x37f86785 0x37f80e3f 0x35ab1b01 0x35ab112f 0x35ab0351
0x35a334a5 0x35a3336d 0x376cf439 0x3353fcd5 0x2dd9 0x2d74)
terminate called throwing an exception(lldb)
方法
它位于 Kumulos.m 文件中。
-(KSAPIOperation*) createNewTimePointWithJourneyIDFK:(NSInteger)journeyIDFK
andTime:(NSDate*)time andLat:(float)lat andLon:(float)lon{
NSMutableDictionary* theParams = [[NSMutableDictionary alloc]init];
[theParams setValue:[NSNumber numberWithInt:journeyIDFK] forKey:@"journeyIDFK"];
[theParams setValue:time forKey:@"time"];
[theParams setValue:[NSNumber numberWithFloat:lat] forKey:@"lat"];
[theParams setValue:[NSNumber numberWithFloat:lon] forKey:@"lon"];
KSAPIOperation* newOp = [[KSAPIOperation alloc]initWithAPIKey:theAPIKey
andSecretKey:theSecretKey andMethodName:@"createNewTimePoint"
andParams:theParams];
[newOp setDelegate:self];
[newOp setUseSSL:useSSL];
//we pass the method signature for the kumulosProxy callback on this thread
[newOp setCallbackSelector:@selector( kumulosAPI: apiOperation: createNewTimePointDidCompleteWithResult:)];
[newOp setSuccessCallbackMethodSignature:[self methodSignatureForSelector:@selector(apiOperation: didCompleteWithResult:)]];
[newOp setErrorCallbackMethodSignature:[self methodSignatureForSelector:@selector(apiOperation: didFailWithError:)]];
[opQueue addOperation:newOp];
return newOp;
}