如何从其他类更新Swing JTextField？

Question

首先，我已经搜索了这个。有没有答案？是的，但我似乎无论如何都无法工作。我对Java的经验非常少，所以我不太了解。

无论如何，我的主要课程名为Game，我也有GameFrame

Game

package xd.winkler.guessing_game;

import java.awt.Canvas;
import java.util.Random;
import java.util.Scanner;

// main game class
public class Game extends Canvas implements Runnable {

// variables
private static final long serialVersionUID = 2723208685741428944L;

public static final int WIDTH = 640, HEIGHT = 480;
public final String TITLE = "Number Guessing Game";

private Thread thread;

Scanner s = new Scanner(System.in);
Random r = new Random();
Boolean running = false, gameOver = false;
static int rounds = 0, tries = 0;;
static int userGuess = 0, randNum = 0;

// creates a new frame called GameFrame
public Game() {
    new GameFrame(WIDTH, HEIGHT, TITLE, this);
    System.out.println("[" + TITLE + " has started.]");
}

// called in the GameFrame class. starts the thread/game loop
public synchronized void start() {
    if (running)
        return;
    thread = new Thread(this);
    thread.start();
    running = true;
}

// called at the end of the game loop. stops the program from running
public synchronized void stop() {
    try {
        thread.join();
    } catch (InterruptedException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    running = false;
    s.close();
}

// game loop
public void run() {
    while (running) {
        randNum = r.nextInt(10) + 1;
        System.out.println("[Random Number: " + randNum + "]");
        this.gameOverCheck();
        System.out.println("Round: " + rounds);
        while (tries < 3) {
            tries++;
            this.guess();
        }
    }
    stop();
}

// checks if the game is over
public void gameOverCheck() {
    if (rounds == 10) {
        running = false;
    } else {
        rounds++;
    }
}

// gets the users guess and checks if it's right/wrong
public void guess() {
    userGuess = s.nextInt();
    if (userGuess == randNum) {
        System.out.println("RIGHT!");
    } else {
        System.out.println("WRONG!");
    }
}

// creates a new "Game" method to call/create the GameFrame
public static void main(String[] args) {
    new Game();
}
}

GameFrame

package xd.winkler.guessing_game;

import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.ScrollPaneConstants;
import javax.swing.text.DefaultCaret;

public class GameFrame extends Canvas {

private static final long serialVersionUID = -7329745595446257624L;

static JButton enterButton;
public static JTextArea output;
public static JTextField input;
private static String ENTER = "Enter";
public static String testString = "test";
static JPanel panel;

public GameFrame(int WIDTH, int HEIGHT, String TITLE, Game game) {
    JFrame frame = new JFrame(TITLE);

    frame.setPreferredSize(new Dimension(WIDTH, HEIGHT));
    frame.setMaximumSize(new Dimension(WIDTH, HEIGHT));
    frame.setMinimumSize(new Dimension(WIDTH, HEIGHT));

    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setResizable(false);
    frame.setLocationRelativeTo(null);

    // ---------------------------------------------------
    // I did not do this section on my own and it's a mess
    // ---------------------------------------------------

    panel = new JPanel();
    panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));
    panel.setOpaque(true);

    ButtonListener buttonListener = new ButtonListener();
    output = new JTextArea(15, 50);
    output.setWrapStyleWord(true);
    output.setEditable(false);
    JScrollPane scroller = new JScrollPane(output);
    scroller.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
    scroller.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
    JPanel inputpanel = new JPanel();
    inputpanel.setLayout(new FlowLayout());
    input = new JTextField(20);
    enterButton = new JButton("Enter");
    enterButton.setActionCommand(ENTER);
    enterButton.addActionListener(buttonListener);
    // enterButton.setEnabled(false);
    input.setActionCommand(ENTER);
    input.addActionListener(buttonListener);
    DefaultCaret caret = (DefaultCaret) output.getCaret();
    caret.setUpdatePolicy(DefaultCaret.ALWAYS_UPDATE);
    panel.add(scroller);
    inputpanel.add(input);
    inputpanel.add(enterButton);
    panel.add(inputpanel);
    frame.getContentPane().add(BorderLayout.CENTER, panel);
    frame.pack();

    // ---------------------------------------------------

    frame.add(game);
    frame.pack();
    frame.setVisible(true);
    input.requestFocus();
    game.start();
}

public static class ButtonListener implements ActionListener {

    public void actionPerformed(final ActionEvent ev) {
        if (!input.getText().trim().equals("")) {
            String cmd = ev.getActionCommand();
            if (ENTER.equals(cmd)) {
                output.append(input.getText());
                if (input.getText().trim().equals(testString))
                    output.append(" = " + testString);
                else
                    output.append(" != " + testString);
                output.append("\n");
            }
        }
        input.setText("");
        input.requestFocus();
    }
}

}

你可以说游戏还没有完成。我只是乱搞并使用系统输出来测试。我想在Game类中完成所有主要的“游戏内容”，然后输出到我拥有的swing输出文本字段。我还想使用输入框来设置userGuess。

我不确定如何在两个班级中使用不同的值，而且就像我说的那样，我已经搜索了它并且看起来和吸气者和制定者但是我并不理解它。此外，如果您可以推荐一个很好的教程网站或者其他东西，以便用Java获得很好的知识。