Question

am trying to add an array i get from NSURL into an array using for loop:

(int i = 0; i < 10; i++) 

to make it 2 dimensional array. Keep getting error on NSRangeException. It can only insertObject or addObject at index[0] and when ‘i’ increase to 1, it throws an error. It can only mean that its not adding but overwriting so when it overwrites the second time and i = 1, it throws the error. How do i add more instead of overwriting the initialized 2 dimensional arrays?

- (void)qBlock{
    for (int i = 0; i < 10; i++) {
        NSURL *url = [NSURL URLWithString:@"http://somefiles.php"];
        NSError *error;
        NSStringEncoding encoding;
        NSString *response = [[NSString alloc] initWithContentsOfURL:url 
                                                        usedEncoding:&encoding 
                                                               error:&error];
        if (response) {

            const char *convert = [response UTF8String];
            NSString *responseString = [NSString stringWithUTF8String:convert];
            NSMutableArray *sample = [responseString JSONValue];

            block = [[NSMutableArray alloc]init];
        [block insertObject:sample atIndex:i];
        }


    else {
        UIAlertView *alert1 = [[UIAlertView alloc]initWithTitle:@"ALERT" message:@"Internet Connection cannot be established." delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [alert1 show];
    }
}
//Calling 10 blocks of codes
for (id obj in block) {
    NSLog(@"%@",obj);
}

Answer 1

This:

        block = [[NSMutableArray alloc]init];
    [block insertObject:sample atIndex:i];

Is replacing the entire block array with an empty array on each iteration through the for loop.

Move your block array initialization outside of the for loop.