add empty message when there is no data one UITableView

UITableView+emptyMessage.swift

extension UITableView {
    func setEmptyMessage(_ message: String) {
        let messageLabel = UILabel(frame: CGRect(x: 0, y: 0, width: self.bounds.size.width, height: self.bounds.size.height))
        messageLabel.text = message
        messageLabel.textColor = .black
        messageLabel.numberOfLines = 0;
        messageLabel.textAlignment = .center;
        messageLabel.font = UIFont.preferredFont(forTextStyle: .title3)
        messageLabel.sizeToFit()

        self.backgroundView = messageLabel;
    }

    func restore() {
        self.backgroundView = nil
    }
}