adding custom navigation bar in viewwillappear makes navigation slow? - ios

Question

I have created a custom navigation bar.Now i am adding this into viewwillappear method.Due to this when i return to my view controller it takes time to load.
func addViewToNav()
{
myView = UIView(frame: CGRect(x: 0, y: 20, width: (self.navigationController?.navigationBar.frame.size.width)!-40, height: (self.navigationController?.navigationBar.frame.size.height)!))
imageView.frame = CGRect(x: 5, y: (myView?.frame.size.height)!/2-14, width: 28, height: 28)
let image = UIImage(named: "download")
imageView.contentMode=UIViewContentMode.scaleAspectFill
imageView.image=image
imageView.layer.borderColor = UIColor.white.cgColor
imageView.layer.cornerRadius = imageView.frame.size.width/2
imageView.clipsToBounds = true
imageView.backgroundColor=UIColor.yellow
label = UILabel(frame: CGRect(x: imageView.frame.size.width+15, y: 0, width: 150, height: (myView?.frame.size.height)!))
label?.text="Label"
label?.textColor=UIColor.white
myView?.addSubview(imageView)
myView?.addSubview(label!)
self.navigationController?.view.addSubview(myView!)
//add tap gesturte on imageview & label
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(self.tapBlurButton(_:)))
myView?.isUserInteractionEnabled=true
tapGesture.numberOfTapsRequired=1
myView?.addGestureRecognizer(tapGesture)
}
Please guide how can i make it fast because this is very slow.

Answer 1

It is taking time because every time the controller appears on the screen viewWillAppear will be called and each time the code for creating the custom view, adding it as the subview and then adding gesture recognizer will be executed.
There are 2 ways that might reduce the processing time:
If you want to do it programatically, the add the code to create and add custom navigation bar in viewDidLoad instead of viewWillAppear
Add the custom navigation bar in the storyboard itself and create an outlet connection for it in the controller.