ios swift button enable with multiple textfields

ios swift button enable with textfields

   class ViewController: UIViewController,UITextFieldDelegate {

    @IBOutlet weak var text1: UITextField!
    @IBOutlet weak var text2: UITextField!
    @IBOutlet weak var button1Outlet: UIButton!
    
   
   func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
        var t1 = text1.text
        if(textField.tag == 0){
            print(string)
            t1 = (text1.text! as NSString).replacingCharacters(in: range, with: string)

            os_log("%@", "text1 is \(String(describing: t1))")
        }
        var t2 = text2.text
        if(textField.tag == 1){
            print(string)
            t2 = (text2.text! as NSString).replacingCharacters(in: range, with: string)
            os_log("%@", "text2 is \(String(describing: t2))")
        }
        let isButtonActive = (t1?.isEmpty)! || (t2?.isEmpty)!
        button1Outlet.isEnabled = !isButtonActive

        return true
    }
 }