How to add a button to UINavigationBar programmatically?
Adding custom button to navigation bar ( with image for buttonItem and specifying action method (void)openView{} and).
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
button.frame = CGRectMake(0, 0, 32, 32);
[button setImage:[UIImage imageNamed:@"settings_b.png"] forState:UIControlStateNormal];
[button addTarget:self action:@selector(openView) forControlEvents:UIControlEventTouchUpInside];
UIBarButtonItem *barButton=[[UIBarButtonItem alloc] init];
[barButton setCustomView:button];
self.navigationItem.rightBarButtonItem=barButton;
[button release];
[barButton release];