Question regarding iPhone error

when i run my below code it gives this response on my device....

- (void) requestProductData
{
 //
 NSString *str = [[NSString alloc] initWithFormat:@"com.mycompany.inapppurchasetesting.productid"];//Same as the Product Id displayed in Itunes Connect//"]; 

 SKProductsRequest *request= [[SKProductsRequest alloc] initWithProductIdentifiers:[NSSet setWithObject:str]]; 

 request.delegate = self;

 [request start];
 //
 //NSSet *productIDs = [NSSet setWithObjects:@"com.mycompany.inapppurchasetesting.productid", nil];

 //SKProductsRequest *request = [[SKProductsRequest alloc] initWithP开发者_开发知识库roductIdentifiers:productIDs];

 //request.delegate = self;

 NSLog(@"Requesting");

 //[request start];
}

- (void)productsRequest:(SKProductsRequest *)request didReceiveResponse:(SKProductsResponse *)response
{
    NSArray *myProduct = response.products;

 NSArray *myInvalidProducts = response.invalidProductIdentifiers;

 NSLog(@"Did recieve response");

    NSLog(@"Response count is %d",response.products.count);
 NSLog(@"Invalid response count is %d",response.invalidProductIdentifiers.count);

 for (int i = 0; i<myProduct.count; i++)
 {
  NSLog(@"t:%@",[[myProduct objectAtIndex:i] localizedTitle]);
 }

 for(int i = 0; i < myInvalidProducts.count; ++i)
 {
  NSLog(@"Invalid products:%@",[[myInvalidProducts objectAtIndex:i] localizedTitle]);
    }

 // populate UI
 [request autorelease];
}

2010-11-16 14:14:46.028 InAppPurchaseTesting[7357:307] View is loaded

2010-11-16 14:14:46.164 InAppPurchaseTesting[7357:307] Requesting

2010-11-16 14:14:46.196 InAppPurchaseTesting[7357:307] can make payments

2010-11-16 14:14:52.135 InAppPurchaseTesting[7357:307] Did recieve response

2010-11-16 14:14:52.146 InAppPurchaseTesting[7357:307] Response count is 0

2010-11-16 14:14:52.152 InAppPurchaseTesting[7357:307] Invalid response count is 1

2010-11-16 14:14:52.160 InAppPurchaseTesting[7357:307] -[NSCFString localizedTitle]: unrecognized selector sent to instance 0x114990

2010-11-16 14:14:52.181 InAppPurchaseTesting[7357:307] * Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSCFString localizedTitle]: unrecognized selector sent to instance 0x114990'

why the above error occurs...

please guide me out...

Because invalidProductIdentifiers only contains an array of NSStrings, not SKProducts.

See the StoreKit documentation.

NSLog(@"Invalid products:%@",[myInvalidProducts objectAtIndex:i]);

Aren't you trying to call "localizedTitle" on NSCFString instead of a Product?