Swift - Pulse Animation

Code : 

override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        
        
        // declare a pulsing layer
        var pulsingLayer = YQPulsingLayer()
        
        // place the pulsing layer in the center the object view
        pulsingLayer.position = objectView.center
        
        // add the pulsing layer to the view
        view.layer.insertSublayer(pulsingLayer, below: objectView.layer)
    }

Link : https://github.com/yiqin/Pulse-Animation