Tab Bar Item won't show - ios

Question

Currently I have 1 tab view controller, with 3 menus:
But when running, the bottom menu / image are like being cutted or didn't show perfectly like this:
It should have 3 menus.
Code:
import UIKit
class TabBarReimbursementViewController: UITabBarController{
var loadTable: Bool = false
override func viewWillAppear(animated: Bool) {
self.viewControllers![selectedIndex].viewWillAppear(true)
}
override func viewDidLoad() {
super.viewDidLoad()
// self.tabBar.barTintColor = UIColor.redColor()
self.tabBar.tintColor = UIColor.blackColor()
let addButton = UIBarButtonItem(barButtonSystemItem: .Add, target: self, action: #selector(TabBarReimbursementViewController.buttonClicked(_:)))
navigationItem.rightBarButtonItem = addButton
// UITabBarItem.appearance().setTitleTextAttributes([NSForegroundColorAttributeName: UIColor.whiteColor() ], forState: .Normal)
UITabBarItem.appearance().setTitleTextAttributes([NSForegroundColorAttributeName: UIColor.blackColor() ], forState: .Selected)
let historySelected: UIImage! = UIImage(named: "history2.png")?.imageWithRenderingMode(.AlwaysOriginal)
let approvalSelected: UIImage! = UIImage(named: "approve2.png")?.imageWithRenderingMode(.AlwaysOriginal)
let listSelected: UIImage! = UIImage(named: "listlist2.png")?.imageWithRenderingMode(.AlwaysOriginal)
(tabBar.items![1] ).selectedImage = historySelected
(tabBar.items![0] ).selectedImage = approvalSelected
(tabBar.items![2] ).selectedImage = listSelected
self.selectedViewController = self.viewControllers![1]
self.findHamburguerViewController()?.gestureEnabled = false
}
func buttonClicked(sender: UIBarButtonItem) {
let storyBoard : UIStoryboard = UIStoryboard(name: "Main", bundle:nil)
let nextViewController = storyBoard.instantiateViewControllerWithIdentifier("MyRequestForm") as! myRequestForm
nextViewController.formType = "New"
self.navigationController!.pushViewController(nextViewController, animated: true)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}

Answer 1

You CAPSPageMenu Library in which you can use tab bar controller very easily CAPSPageMenu
just add below code in Library
_menuScrollView.translatesAutoresizingMaskIntoConstraints = NO;
_menuScrollView.frame = CGRectMake(0.0, self.view.frame.size.width- _menuHeight,self.view.frame.size.width, _menuHeight);

Answer 2

The thing is that what you are doing is not how a tab bar controller's tab bar items work. Each child view controller (there are three of them in your storyboard screen shot) has its own tabBarItem, and that is how the tab bar gets populated.