ContactsTabNavigationController.h

#import <UIKit/UIKit.h>

@interface ContactsTabNavigationController : UINavigationController {
    UIProgressView *progress;
}

@property (nonatomic, retain) UIProgressView *progress;

@end

ContactsTabNavigationController.m

#import "ContactsTabNavigationController.h"

@interface ContactsTabNavigationController ()

@end

@implementation ContactsTabNavigationController

@synthesize progress;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    
    progress = [[UIProgressView alloc] init];
    
    [[self view] addSubview:progress];
    
    
    UIView *navBar = [self navigationBar];
    [[self view] addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:[navBar]-[progress(2@20)]"
                                                                        options:NSLayoutFormatDirectionLeadingToTrailing
                                                                        metrics:nil
                                                                          views:NSDictionaryOfVariableBindings(progress, navBar)]];
    
    [[self view] addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[progress]|"
                                                                        options:NSLayoutFormatDirectionLeadingToTrailing
                                                                        metrics:nil
                                                                          views:NSDictionaryOfVariableBindings(progress)]];
    
    [progress setTranslatesAutoresizingMaskIntoConstraints:NO];
    
    [progress setProgress:0.5 animated:YES];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

/*
#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
}
*/

@end