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

Swift 3.0

// UIView Extension

fileprivate var ActivityIndicatorViewAssociativeKey = "ActivityIndicatorViewAssociativeKey"
public extension UIView {
   var activityIndicatorView: UIActivityIndicatorView {
        get {
            if let activityIndicatorView = getAssociatedObject(&ActivityIndicatorViewAssociativeKey) as? UIActivityIndicatorView {
                return activityIndicatorView
            } else {
                let activityIndicatorView = UIActivityIndicatorView(frame: CGRect(x: 0, y: 0, width: 40, height: 40))
                activityIndicatorView.activityIndicatorViewStyle = .gray
                activityIndicatorView.color = .gray
                activityIndicatorView.center = center
                activityIndicatorView.hidesWhenStopped = true
                addSubview(activityIndicatorView)

                setAssociatedObject(activityIndicatorView, associativeKey: &ActivityIndicatorViewAssociativeKey, policy: .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
                return activityIndicatorView
            }
        }

        set {
            addSubview(newValue)
            setAssociatedObject(newValue, associativeKey:&ActivityIndicatorViewAssociativeKey, policy: .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
        }
    }
}

// NSObject Extension

public extension NSObject {
    func setAssociatedObject(_ value: AnyObject?, associativeKey: UnsafeRawPointer, policy: objc_AssociationPolicy) {
        if let valueAsAnyObject = value {
            objc_setAssociatedObject(self, associativeKey, valueAsAnyObject, policy)
        }
    }

    func getAssociatedObject(_ associativeKey: UnsafeRawPointer) -> Any? {
        guard let valueAsType = objc_getAssociatedObject(self, associativeKey) else {
            return nil
        }
        return valueAsType
    }
}

start animation

tableView.activityIndicatorView.startAnimating()

stop animation

tableView.activityIndicatorView.stopAnimating()

You can find more code in Magic