How to show activity indicator while tableView loads?

Question

When I switch between my tabs it loads some seconds and I want to know that my data is loading. For that I decided to add an activity indicator.

I wrote a little functio

Answer 1

Using "lazy var". It's better than function

fileprivate lazy var activityIndicatorView: UIActivityIndicatorView = {
    let activityIndicatorView = UIActivityIndicatorView(activityIndicatorStyle: .gray)
    activityIndicatorView.hidesWhenStopped = true

    // Set Center
    var center = self.view.center
    if let navigationBarFrame = self.navigationController?.navigationBar.frame {
        center.y -= (navigationBarFrame.origin.y + navigationBarFrame.size.height)
    }
    activityIndicatorView.center = center

    self.view.addSubview(activityIndicatorView)
    return activityIndicatorView
}()

Just start the spinner anywhere

like this

func requestData() {
  // Request something
  activityIndicatorView.startAnimating()
}