iOS 13 tabbar layout delay when using setHidesBottomBarWhenPushed

[ibespaljkocs]

Description

UITabbar has a layout delay if setHidesBottomBarWhenPushed is set to YES when opening another screen (e.g: details screen with no bottom tabbar). Layout delay happens on back action, when user returns to previous screen.
This is present only on iOS 13 when not using storyboards!

iOS 13 + storyboard -> OK.
iOS < 13 + storyboards -> OK.
iOS < 13 w/o storyboards -> OK (e.g: using nibs or manually creating UITabBarController)
Also, it works OK on any iOS if animations are turned off with [UIView setAnimationsEnabled:NO]

Steps to Reproduce

0. Do not use storyboard (except the LaunchScreen.storyboard)
1. Use a UITabBarController as a rootViewController of your main window
2. From selected tab, go to another UIViewController (e.g: DetailsVC) with option setHidesBottomBarWhenPushed set to YES, to hide the bottom bar.
3. On DetailsVC show PopupBar by calling [self.tabBarController presentPopupBarWithContentViewController:dummyVC animated:YES completion:nil];
4. Return to rootViewController with back action.

Behaviour: PopupBar is moved up as expected, but UITabbar is shown with some delay.
Video: https://drive.google.com/file/d/1mZCrRn07NXj0MT4ji4XD_HCG9wjFvibG/view

Device, OS and Xcode Versions

iPhone SE, iPhone 11 with iOS 13 (confirmed on 13.4.1 also)

[LeoNatan]

Heh, what an odd issue. I don't see why a storyboard presence would influence the layout timing, unless Apple is doing something fishy.

I don't have much time these days, but I will take a look when I can. Thanks

[ibespaljkocs]

Yes, sounds strange, I agree.
I've just created a simple storyboard with only UITabBarController in it..then subclassed UITabBarController with custom class, assigned it to UITabBarController class in storyboard. Now it works like a charm!

[ivanrein]

@ibespaljkocs do you have a workaround for this?

[LeoNatan]

I'll look at this tomorrow. I haven't seen this reproduce, but will try to.

[LeoNatan]

Reproduced, investigating.

[LeoNatan]

Fixed. For some reason, when the tab bar is not created from a storyboard, the frame was being overridden. Should work well now.