text.swift

            let width = self.view.layer.bounds.width
            let view = UIView(frame: CGRect(x: 0, y: 0, width: width-100, height: 40))
            let titleLabel = UILabel(frame: CGRect(x: 0, y: 0, width: width-100, height: 40))
            titleLabel.textAlignment = .center
            titleLabel.text = "\(petsName)'s Day"
            titleLabel.font = UIFont.systemFont(ofSize: 30)
            titleLabel.backgroundColor = UIColor.clear
            titleLabel.textColor = UIColor.white
            titleLabel.adjustsFontSizeToFitWidth = true
            titleLabel.minimumScaleFactor = 0.5
            view.addSubview(titleLabel)
            self.navBar.topItem?.titleView = view