// CREATE & ADD SPINNER
UIActivityIndicatorView *activityIndicator = 
    [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(0, 0, 20, 20)];
UIBarButtonItem * barButton = 
    [[UIBarButtonItem alloc] initWithCustomView:activityIndicator];
 
// Set to Left or Right
[[self navigationItem] setRightBarButtonItem:barButton];
 
[barButton release];
[activityIndicator startAnimating];




// REMOVE SPINNER
[[self navigationItem] setLRightBarButtonItem:nil];
[activityIndicator stopAnimating];
[activityIndicator release];

http://iphonedevelopertips.com/user-interface/adding-an-activity-indicator-spinner-to-navigation-bar.html

Create a Busy Activity Indicator Spinner

iphone

Objective C