UIViewController extension for hidding UITabBarController

UIViewController+TabBarAnimations

import UIKit

extension UIViewController {

    func setTabBarVisible(visible:Bool, animated:Bool) {

        //* This cannot be called before viewDidLayoutSubviews(), because the frame is not set before this time

        // bail if the current state matches the desired state
        if (tabBarIsVisible() == visible) { return }

        // get a frame calculation ready
        let frame = self.tabBarController?.tabBar.frame
        let height = frame?.size.height
        let offsetY = (visible ? -height! : height)

        // zero duration means no animation
        let duration:NSTimeInterval = (animated ? 0.3 : 0.0)

        //  animate the tabBar
        if frame != nil {
            UIView.animateWithDuration(duration) {
                self.tabBarController?.tabBar.frame = CGRectOffset(frame!, 0, offsetY!)
                return
            }
        }
    }

    func tabBarIsVisible() -> Bool {
        return self.tabBarController?.tabBar.frame.origin.y < UIScreen.mainScreen().bounds.height
    }
}

So force unwrapping causes crashed. Be aware of that!

I created a version here: https://gist.github.com/brindy/b93d0cd0ce4ca3560225ade23f4cf35e

I figured if you make it an extension of the UITabBarViewController you can get rid of a lot of that optional/force unwrapping stuff. Then just call it safely from your view controller (in viewWillAppear usually) like this:

tabBarController?.setTabBarVisible(visible: false, animated: true)