Xcode warning - addObject

I'm using the following method:

-(void) finishQuestionnaire:(id)sender{ 
    NSString * ans;
    NSString* qt = [[[questionArray objectAtIndex:currQNum-1] question] qType];     
    if([qt isEqualToString:@"Slider"]){
        ans = [[[questionArray objectAtIndex:currQNum-1] sliderLabel]text];
    }else if([qt isEqualToString:@"Option"]){               

    }else if([qt isEqualToString:@"TextInput"]){
        ans = [[[questionArray objectAtIndex:currQNum-1] inputAnswer]text];
    }else if([qt isEqualToString:@"ImagePicker"]){

    }else if([qt isEqualToString:@"Comment"]){
        ans = [[[questionArray objectAtIndex:currQNum-1] inputAnswer]text];             
    }
    //UPDATED

NSLog(@"%@", [questionArray objectAtIndex:currQNum-1]);
NSLog(@"%@", [[questionArray objectAtIndex:currQNum-1] question]);
NSLog(@"%@", [[[questionArray objectAtIndex:currQNum-1] question] answer]);

    //[self.navigationController popToRootViewControllerAnimated:YES];
}

when qt = comment, I get the following error and the app crashes:

 2011-07-20 00:02:04.723 MainMenu[71393:207] -[NSURLCache setAnswer:]: unrecognized selector sent to instance 0x4e29280
    2011-07-20 00:02:04.726 MainMenu[71393:207] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSURLCache setAnswer:]: unrecognized selector sent to instance 0x4e29280'

I'm not sure what I am doing wrong....It works when qt is equal to the slider and textinput...

Answer and Question Class

import <Foundation/Foundation开发者_StackOverflow社区.h>


@interface Answer : NSObject {
    //NSString* answerId;
    NSString* answer;
    NSString* questionId;
    NSString* entryId;
}

//@property (nonatomic, retain) NSString* answerId;
@property (nonatomic, retain) NSString* answer;
@property (nonatomic, retain) NSString* questionId;
@property (nonatomic, retain) NSString* entryId;

@end


#import "Answer.h"


@implementation Answer

@synthesize answer, questionId, entryId;

@end

#import <Foundation/Foundation.h>
#import "Answer.h"

@interface Question : NSObject {
    NSString* qId;
    NSString* qTitle;
    NSString* qNumber;  
    NSString* sectionId;
    NSString* qType;
    Answer* answer;
}

@property (nonatomic, retain) NSString* qId;
@property (nonatomic, retain) NSString* qTitle;
@property (nonatomic, retain) NSString* qNumber;
@property (nonatomic, retain) NSString* sectionId;
@property (nonatomic, retain) NSString* qType;
@property (nonatomic, retain) Answer* answer;

@end


@implementation Question
@synthesize qId, qTitle, qNumber, sectionId, qType, answer;

-(id)init
{
    if (self = [super init])
    {
        // Initialization code here
        answer = [[Answer alloc]init];
    }
    return self;
}

-(void) dealloc{
    [answer release];
    [super dealloc];
}

Edit: see update code, here is the output:

2011-07-20 01:21:04.402 MainMenu[71910:207] <CommentQuestionViewController: 0x4e0b100>
2011-07-20 01:21:04.404 MainMenu[71910:207] <Question: 0x4e55170>
2011-07-20 01:21:04.404 MainMenu[71910:207] (null)

Update:

Now I'm not even getting null. My output is just:

2011-07-20 01:21:04.402 MainMenu[71910:207] <CommentQuestionViewController: 0x4e0b100>
2011-07-20 01:21:04.404 MainMenu[71910:207] <Question: 0x4e55170>

Your custom type Answer does not appear to have a method setAnswer.

Make sure that

[[[questionArray objectAtIndex:currQNum-1] question] answer];

returns an object of type Answer (it appears to be of type NSURLCache), and then check that the answer property of Answer has a setter method.

EDIT: To solve this problem without posting your entire source code, start at the beginning and work your way down. By this, I mean answer the following, in order:

1. Of what type is [questionArray objectAtIndex:currQNum-1]?
2. Of what type is [[questionArray objectAtIndex:currQNum-1] question]?
3. Of what type is [[[questionArray objectAtIndex:currQNum-1] question] answer]?

Perhaps Answer is a subclass of NSURLCache. In your custom subclass header and implementation files, make sure you have defined and written a selector called -setAnswer:. Either that, or make sure you are storing an Answer instance in questionArray, and not an NSURLCache instance.

EDIT

The following:

@implementation Answer

@synthesize answer, questionId, entryId;

@end

should be fleshed out. Is this all you have in Answer.m?