How do I disable the navigation bar shadow in iOS

Question

It seems in iOS 6, a drop shadow is automatically added to the navigation bar even when you set a custom background image. I'm pretty sure this wasn't the case with iOS 5 as when I test the same code in the iOS 5 and 6 sim, the shadow appears in iOS 6 but not 5.

Does anyone know anything about this? Or how to enable/disable it?

Answer 1

Setting the shadowImage to a null image does work, however, the way the solution is presented results in adding a property if the OS is earlier than iOS 6.

A better way to do something that is dependent on the existence of a property or method is:

if ([self.navigationController.navigationBar
respondsToSelector:@selector(shadowImage)]) {
self.navigationController.navigationBar.shadowImage = [[[UIImage alloc] init] autorelease];
}

Answer 2

In Swift 3.0 this would look like this

UINavigationBar.appearance().shadowImage = UIImage ()
UINavigationBar.appearance().setBackgroundImage(UIImage(), for: .default)

Answer 3

Since self.navigationController.navigationBar.shadowImage = [[UIImage alloc] init]; not working, I've found an easy and workable way to remove the shadow of UINavigationBar in both iOS 6 AND iOS 5. Hope people who need can see this post.

All you have to do is prepare one background image that the height is 1 pixel larger than your navigation bar height (e.g. 320×45 for default UINavigationBar, 640×90 for 2x of course).

Then just use [[UINavigationBar appearance] setBackgroundImage: ...], you will find shadow is replaced by that 1 pixel. cheers!

BTW I found Twitter has done the exactly same thing, if you unzip Twitter.ipa and look into bg_nav_bar_events_dark.png, the size is 320×47. They made their own shadow for 3 pixels :)

Answer 4

I came across this SO question when trying to get nav bars to look the same between iOS6 and iOS7.

The answer I found worked was simply to use:

    NSMutableDictionary *titleBarAttributes = [NSMutableDictionary dictionaryWithDictionary: [[UINavigationBar appearance] titleTextAttributes]];
    [titleBarAttributes setValue:[NSNumber numberWithInt:0] forKey:UITextAttributeTextShadowOffset];
    [[UINavigationBar appearance] setTitleTextAttributes:titleBarAttributes];

ie: set the shadow offset to zero.

Answer 5

I know this has been solved with more complicated answers above, but this is the quickest and easiest way I hid the shadow under the navigation bar.

self.navigationController.navigationBar.clipsToBounds = YES;

Answer 6

Note from the Apple dev docs on the subject of the shadowImage property:

Discussion: The default value is nil, which corresponds to the default shadow image. When non-nil, this property represents a custom shadow image to show instead of the default. For a custom shadow image to be shown, a custom background image must also be set with the setBackgroundImage:forBarMetrics: method. If the default background image is used, then the default shadow image will be used regardless of the value of this property.

So to use the nil UIImage hack you must also be setting a custom nav bar background image. This can be a nil image too, which results in a nice flat, clean 'metro' style nav bar :

[[UINavigationBar appearance] setShadowImage:[[UIImage alloc] init]];
        [[UINavigationBar appearance] setBackgroundImage:[[UIImage alloc] init] forBarMetrics:UIBarMetricsDefault];