I'm working through "iPhone Development: The Big Nerd Ranch Guide". The project is "Random Possessions". I am faithfully following the code in the book and it compiles OK but I get this exception when running it:
**2010-07-04 11:43:48.511 RandomPosessions[14828:a0f] -[Posession initWithPosessionName:valueInDollars:serialNumber:]: unrecognized selector sent to instance 0x10010d1f0 2010-07-04 11:43:48.514 RandomPosessions[14828:a0f] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[Posession initWithPosessionName:valueInDollars:serialNumber:]: unrecognized selector sent to instance 0x10010d1f0' *** Call stack at first throw: ( 0 CoreFoundation 0x00007fff80b4bcc4 __exceptionPreprocess + 180 1 libobjc.A.dylib 0x00007fff8044b0f3 objc_exception_throw + 45 2 CoreFoundation 0x00007fff80ba5140 +[NSObject(NSObject) doesNotRecognizeSelector:] + 0 3 CoreFoundation 0x00007fff80b1dcdf ___forwarding___ + 751 4 CoreFoundation 0x00007fff80b19e28 _CF_forwarding_prep_0 + 232 5 RandomPosessions 0x00000001000016c2 +[Posession randomPosession] + 995 6 RandomPosessions 0x0000000100001196 main + 170 7 RandomPosessions 0x00000001000010e4 start + 52 ) terminate called after throwing an instance of 'NSException'**
THis is my code for the implementation for "RandomPosession":
#import "Posession.h"
@implementation Posession
@synthesize posessionName, serialNumber, valueInDollars, dateCreated;
-(NSString *) description {
NSString *descriptionString =
[[NSString alloc] initWithFormat:@"%@ (%@): Worth $%@, Recorded on %@",
posessionName,
serialNumber,
valueInDollars,
dateCreated];
return descriptionString;
}
+(id)randomPosession
{
static NSString *randomAdjectiveList[3] =
{
@"Fluffy",
@"Rusty",
@"Shiny"
};
static NSString *randomNounList[3] =
{
@"Bear",
@"Spork",
@"Mac"
};
NSString *randomName = [NSString stringWithFormat:@"%@ %@",
randomAdjectiveList[random() % 3],
randomNounList[random() % 3]];
int randomValue = random() % 100;
NSString *randomSerialNumber = [NSString stringWithFormat:@"%c%c%c%c%c",
开发者_高级运维 '0' + random() % 10,
'A' + random() % 26,
'0' + random() % 10,
'A' + random() % 26,
'0' + random() % 10];
Posession *newPosession =
[[self alloc] initWithPosessionName:randomName
valueInDollars:randomValue
serialNumber:randomSerialNumber];
return newPosession;
}
-(id)init{
return [self initWithPosessionName:@"Posession"
valueInDollars:0
serialNumber:@""];
}
-(id)initWithPosessionName: (NSString *)pName
valuesInDollars:(int)value
serialNumber:(NSString *)sNumber{
[super init];
if(!self)
return nil;
[self setPosessionName:pName];
[self setSerialNumber:sNumber];
[self setValueInDollars:value];
dateCreated = [[NSDate alloc] init];
return self;
}
-(id)initWithPosessionName:(NSString *)pName {
return [self initWithPosessionName:pName
valuesInDollars:0
serialNumber:@""];
}
@end
I'm pulling my hair out by clumps! I'd appreciate any help Cheers
You need to format your input better....
But your issue is you defined the method incorrectly
-(id)initWithPosessionName: (NSString *)pName valuesInDollars:(int)valueserialNumber:(NSString *)sNumber
that should be
-(id)initWithPosessionName: (NSString *)pName valueInDollars:(int)valueserialNumber:(NSString *)sNumber
You had an extra 's'
I can almost guarantee Xcode was giving you warnings about this. In Objective-C warnings are generally going to cause you runtime crashes, such as this. It is a good habit to clean up all your warnings before giving up on an issue.
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