View on Top of UITabBar

Question

Similar to what the Spotify or Apple Music app does when a song is playing, it places a custom view on top of the UITabBar:

Solutions I\'ve tried:

1. UITa

Answer 1

Your idea to put it in a wrapper viewcontroller is good, but it will only cause overhead (more viewcontrollers to load in memory), and issues when you want to change the code later on. If you want the bar to always show on your UITabBarController, then you should add it there.

You should subclass UITabBarController and load the custom bar from a nib. There you will have access to the tabbar (so you can place your bar correctly above it), and you will only load it in once (which solves your problem that you will face having a different bar on each tab).

As for your views not reacting to the size of the custom bar, I don't know how you can do that, but my best suggestion is to use a public variable and notifications that you listen to in your individual tabs.
You can then use that to change the bottom constraint.