Swift 4
Вам нужен подкласс TabBarController и манипулируйте им.
import UIKit
class CustomTabBarViewController: UITabBarController {
let btn = UIButton() //Here create your button
override func viewDidLoad() {
super.viewDidLoad()
//Here set up your button
self.view.insertSubview(btn, belowSubview: self.tabBar) //<--This is important.
//With this call you have a button that is over all view but under the tab bar.
//So if you have a round button that it expanded on click, the expanded
//part could be hidden by the tab bar, if it is near to tab bar.
//Other button's setting if you need
btn.translatesAutoresizingMaskIntoConstraints = false //<- Important
//Because you are adding the button programmatically you need set the
//constraints. to do it, you need set to false the autoresizing mask.
//Here set the constraints.
//These constraints put the button in the lower right corner, over the tab bar
let viewDictionary = ["button":btn, "tabBar":self.tabBar]
let btn_V = NSLayoutConstraint.constraints(withVisualFormat: "V:[button(340)]", options: NSLayoutFormatOptions(rawValue: 0), metrics: nil, views: viewDictionary)
let btn_H = NSLayoutConstraint.constraints(withVisualFormat: "H:[button(340)]", options: NSLayoutFormatOptions(rawValue: 0), metrics: nil, views: viewDictionary)
let btn_POS_V = NSLayoutConstraint.constraints(withVisualFormat: "V:[button]-(-130)-[tabBar]", options: NSLayoutFormatOptions(rawValue: 0), metrics: nil, views: viewDictionary)
let btn_POS_H = NSLayoutConstraint.constraints(withVisualFormat: "H:[button]-(-129)-|", options: NSLayoutFormatOptions(rawValue: 0), metrics: nil, views: viewDictionary)
btn.addConstraints(btn_V)
btn.addConstraints(btn_H)
self.view.addConstraints(btn_POS_H)
self.view.addConstraints(btn_POS_V)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
}
*/
}
Это результаты