Custom bar between NavigationBar and controller's view

Question

I need to add an offline indicator bar to the app. It needs to be between navigation bar and view controller's view. Offline bar needs to be visible all the time, no matter how many controllers are pushed. Bar cannot overlap anything, so adding subview to navigation bar is not an option.

First approach:

I have added container view and embedded a navigation controller in. The offline bar stays, but navigation bar is under it, and it can't.

Second approach:

Added main navigation controller for navigation bar presentation, wrapped Root into navigation controller. Presentation is proper until I tap "Push child" button. There is no connection between embedded navigation controller and topmost navigation bar, so no title change, no back buttons.

Just make the left most VC embedded in a navigation controller and add a bar in the view of that VC. — Cheng-Yu Hsu
But then the bar will disappear after I push anything. I need the bar to be visible all the time, on any pushed view controller. — Mateusz
You may add the bar to the navigation controller at runtime to achieve this. — Cheng-Yu Hsu
Can you tell me how? Adding subview to navigation bar overlaps its content. — Mateusz

user3820674 user3820674 · Accepted Answer · 2015-10-26T12:39:23

I think you can do it easiest way. First of all you must subclass UINavigationBar. Then override sizeThatFits: and returns a larger size.

#import "MyNavBar.h"

const CGFloat navigationBarHeightIncrease = 38.f;

@implementation MyNavBar

- (CGSize)sizeThatFits:(CGSize)size {

    CGSize amendedSize = [super sizeThatFits:size];
    amendedSize.height += navigationBarHeightIncrease;

    return amendedSize;
}

@end

Then subcalss UINavigationController class and in viewDidLoad: add your custom view:

#import "MyNavController.h"

@interface MyNavController ()

@end

@implementation MyNavController

- (void)viewDidLoad {
    [super viewDidLoad];

    UIView *redOfflineView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 25)];
    redOfflineView.backgroundColor = [UIColor redColor];
    [self.navigationBar addSubview:redOfflineView];
}

@end

I found interesting solutions about nav bar here
Hope it helps.
Cheers.

Custom bar between NavigationBar and controller's view

2 Answers