Spacing navbar buttons so a button is right next to title

Question

I have a navbar with the following:

left: back arrow with the word "back" all the way to the left

right: 2 bar buttons all the way to the right

center: title text

I want to add a third button to the pair buttons on the right (to the left of those buttons), but I want there to be space between this new button and the other buttons such that this new button is hugging up on the right side of the title. I tried using a FixedSpace BarButtonItem. Here's what I've got so far:

UIBarButtonItem* space = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:self action:nil];
space.width = 160;
UIBarButtonItem* thirdButton = [[UIBarButtonItem alloc] initWithImage:myImage style:UIBarButtonItemStylePlain target:self action:@selector(action)];

NSMutableArray* buttons = [self.navigationItem.rightBarButtonItems mutableCopy];       
//index 0 & 1 are the buttons that are already there
[buttons setObject:space atIndexedSubscript:2];
[buttons setObject:button atIndexedSubscript:3];
[self.navigationItem setRightBarButtonItems:buttons];

Doing this does indeed create a space between the third button and the other buttons. Problem is though, the title can be dynamic, and it's not alway center because of this fixed space. Adding a fixed space to the right causes the title to shift to the left and look weird depending on the title size. I need a way to figure out the position of the title and how long it is. Is there a way to do that? Something like navBar.title.width and navBar.title.origin so that I can figure out how many points there are from the very right of the navbar until the title?

Answer 1

To calculate the size of the title in the nav bar, you'll just need to following.

NSDictionary *attributes = [self.navigationController.navigationBar titleTextAttributes];
CGSize titleSize = [self.title sizeWithAttributes:attributes];

Now you can use the size of the title and the size of the buttons to calculate the width of the fixed space.