do {


            // Create the custom dialog.
            Dialog<Pair<String, String>> dialog = new Dialog<>();
            dialog.setTitle("Login Dialog");
            dialog.setHeaderText("Look, a Custom Login Dialog");


            //Set the button types.
            ButtonType dalejButtonType = new ButtonType("Dalej", ButtonBar.ButtonData.OK_DONE);
            ButtonType cancelButton = new ButtonType("Cancel", ButtonBar.ButtonData.CANCEL_CLOSE);
            dialog.getDialogPane().getButtonTypes().addAll(dalejButtonType, cancelButton);


            // Create the username and password labels and fields.
            GridPane grid = new GridPane();
            grid.setHgap(10);
            grid.setVgap(10);
            grid.setPadding(new Insets(20, 150, 10, 10));

            TextField imie = new TextField();
            imie.setPromptText("Imię");
            TextField email = new TextField();
            email.setPromptText("eMail");

            grid.add(new Label("Imię:"), 0, 0);
            grid.add(imie, 1, 0);
            grid.add(new Label("eMail:"), 0, 1);
            grid.add(email, 1, 1);

            // Enable/Disable login button depending on whether a username was entered.
            Node loginButton = dialog.getDialogPane().lookupButton(dalejButtonType);
            loginButton.setDisable(true);

            // Do some validation (using the Java 8 lambda syntax).
            imie.textProperty().addListener((observable, oldValue, newValue) -> {
                loginButton.setDisable(newValue.trim().isEmpty());
            });

            dialog.getDialogPane().setContent(grid);

            // Request focus on the username field by default.
            Platform.runLater(() -> imie.requestFocus());

            // Convert the result to a username-password-pair when the login button is clicked.
            dialog.setResultConverter(dialogButton -> {
                if (dialogButton == dalejButtonType) {
                    return new Pair<>(imie.getText(), email.getText());
                }
                if (dialogButton == cancelButton) {
                    return new Pair<>(imie.getText(), email.getText());
                }
                return null;

            });



            Optional<Pair<String, String>> result = dialog.showAndWait();


           result.ifPresent(usernamePassword -> {
            System.out.println("Username=" + usernamePassword.getKey() + ", Password=" + usernamePassword.getValue());

        } while(flag);