Assigning a button tag from an array which stores integers - iphone

Question

I am trying to assign a tag to button. The normal command is:
button.tag = 1;
The tag must be an integer.
My problem is that I would like to assign an integer which I stored in an array (tabReference) which is yet again part of a class (currentNoteBook). So I need this:
int k = 0;
button.tag = [currentNoteBook.tabReference objectAtIndex:k]; // This is where I get the warning.
This doesn't seem to work, however, as xCode tells me: Passing argument 1 of setTag: makes integer from pointer without a cast.
My array looks like this (I tried to use integers...):
NSMutableArray *trArray = [[NSMutableArray alloc] init];
NSNumber *anumber = [NSNumber numberWithInteger:1];
[trArray addObject: anumber];
[trArray addObject: anumber];
[trArray addObject: anumber];
[trArray addObject: anumber];
currentNoteBook.tabReference = trArray;

Answer 1

An NSMutableArray stores a modifiable array of objects. You can't directly store an integer in an NSMutableArray. That's why you have to do something like this to store a bunch of integers:
NSMutableArray *the_array = [[NSMutableArray alloc] init];
int max = 100;
for (int i = 0; i < max; i++)
{
NSNumber *temp_number = [NSNumber numberWithInt:arc4random() % max];
[the_array addObject:temp_number];
}
Of course, you could do pretty much the same thing and store something else in there:
NSMutableArray *the_array = [[NSMutableArray alloc] init];
int max = 100;
int max_x = 50;
int max_y = 25;
int max_w = 100;
int max_h = 200;
for (int i = 0; i < max; i++)
{
CGFloat temp_x = arc4random() % max_x;
CGFloat temp_y = arc4random() % max_y;
CGFloat temp_w = arc4random() % max_w;
CGFloat temp_h = arc4random() % max_h;
CGRect temp_rect = CGRectMake(temp_x, temp_y, temp_w, temp_h);
[the_array addObject:[NSValue valueWithCGRect:temp_rect]];
}
When you go to retrieve these values you need to specify what it is you want out of the array because the same array can contain very different objects.
For your integers:
for (int i = 0; i < max; i++)
{
NSLog(#"%i: %i", i, [[the_array objectAtIndex:i] intValue]);
}
For the CGRect example:
for (int i = 0; i < max; i++)
{
CGRect temp_rect = [[the_array objectAtIndex:i] CGRectValue];
NSLog(#"%i: x:%f y:%f w:%f h:%f", i, temp_rect.origin.x, temp_rect.origin.y, temp_rect.size.width, temp_rect.size.height);
}
In a nutshell, you are storing objects not integers in your code. You have to pull them out of there as objects and then extract your integer to get your data back.

Answer 2

Just found the answer in another question I posed:
it must be:
btn.tag = [[currentNoteBook.tabReference objectAtIndex:k] intValue];