Java JPanel随着JTextArea的发展而不断增长

我在用JPanel测试一些东西。当我将随机文本添加到JTextArea中时，它会不断增加JPanel的大小，直到到达边缘

如何在不拉伸的情况下将文本保存在JPanel中

public class Game
{
TitleScreenHandler tsHandler = new TitleScreenHandler();
ChoiceHandler choiceHandler = new ChoiceHandler();
ComponentHandler compHandler = new ComponentHandler();      

GridBagConstraints gbc = new GridBagConstraints();
Border whiteline = BorderFactory.createLineBorder(Color.WHITE);

JFrame window; 
Container con;
JPanel titlePanel , startPanel, mainTextPanel, choiceButtonPanel, playerPanel;
JLabel titleLabel, hpLabel, hpLabelNumber, weaponLabel, weaponLabelName;

public static JButton startButton, choice1,choice2,choice3,choice4,choice5,choice6,choice7,choice8;

public static JTextArea mainTextArea;

Font titleFont = new Font("Times New Roman", Font.PLAIN, 100);
Font normalFont = new Font("Times New Roman", Font.PLAIN, 30);

public static String playerName;
public static String weapon,position;

public static int playerHP;
public static int weaponDamage;

public static void main(String[] args)
{
    new Game();

}

public Game()
{
    window = new JFrame();
    window.setSize(1440,900);
    window.setTitle("W: " + window.getWidth() + " H: " + window.getHeight());
    window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    window.getContentPane().setBackground(Color.black);
    window.setLayout(new GridBagLayout());

    con = window.getContentPane();

    //Panels are used to make sections in the window (Background)
    //Labels are used to write in the sections/panels (Foreground)
    //Buttons can be pressed inside Panels

    //To make a text you need to design a panel, design its size/color,
    //Design its text the same way, then add it to the panel

    titlePanel = new JPanel();
    titlePanel.setBounds(100, 100,  1080 , 150);
    titlePanel.setBackground(Color.black);      

    titleLabel = new JLabel("Adventure");
    titleLabel.setForeground(Color.white);
    titleLabel.setFont(titleFont);

    startPanel = new JPanel();
    startPanel.setBounds(540, 600, 200, 100);
    startPanel.setBackground(Color.black);

    startButton = new JButton("START");
    startButton.setBackground(Color.black);
    startButton.setForeground(Color.white);
    startButton.setFont(normalFont);
    startButton.addActionListener(tsHandler);

    window.addComponentListener(compHandler);

    titlePanel.add(titleLabel);
    startPanel.add(startButton);

    con.add(titlePanel, gbc);

    gbc.gridx = 0;
    gbc.gridy = 2;

    con.add(startPanel, gbc);

    window.setVisible(true);
}

public void createGameScreen()
{
    titlePanel.setVisible(false);
    startButton.setVisible(false);

    mainTextPanel = new JPanel();
    //mainTextPanel.setBounds(100, 100, 1080, 250);
    mainTextPanel.setBackground(Color.black);
    mainTextPanel.setBorder(whiteline);

    mainTextArea = new JTextArea("This is the main text area");
    mainTextArea.setBounds(100,100,1080,250);
    mainTextArea.setBackground(Color.black);
    mainTextArea.setForeground(Color.white); 
    mainTextArea.setLayout(new GridLayout());
    mainTextArea.setFont(normalFont);
    mainTextArea.setLineWrap(true);
    mainTextArea.setWrapStyleWord(true);

    playerPanel = new JPanel();
    playerPanel.setBounds(100, 100, 1080, 50);
    playerPanel.setBackground(Color.blue);
    playerPanel.setLayout(new GridLayout(1,4));

    choiceButtonPanel = new JPanel();
    choiceButtonPanel.setBounds(500, 350, 300, 250);
    choiceButtonPanel.setLayout(new GridLayout(2,4, 50, 50));
    choiceButtonPanel.setBackground(Color.red);

    choice1 = new JButton("Choice 1");
    choice1.setBackground(Color.black);
    choice1.setForeground(Color.white);
    choice1.setFont(normalFont);
    choice1.setFocusPainted(false);
    choice1.addActionListener(choiceHandler);
    choice1.setActionCommand("c1");

    choiceButtonPanel.add(choice1);

    choice2 = new JButton("Choice 2");
    choice2.setBackground(Color.black);
    choice2.setForeground(Color.white);
    choice2.setFont(normalFont);
    choice2.setFocusPainted(false);
    choice2.addActionListener(choiceHandler);
    choice2.setActionCommand("c2");

    choiceButtonPanel.add(choice2);

    choice3 = new JButton("Choice 3");
    choice3.setBackground(Color.black);
    choice3.setForeground(Color.white);
    choice3.setFont(normalFont);
    choice3.setFocusPainted(false);
    choice3.addActionListener(choiceHandler);
    choice3.setActionCommand("c3");

    choiceButtonPanel.add(choice3);

    choice4 = new JButton("Choice 4");
    choice4.setBackground(Color.black);
    choice4.setForeground(Color.white);
    choice4.setFont(normalFont);
    choice4.setFocusPainted(false);
    choice4.addActionListener(choiceHandler);
    choice4.setActionCommand("c4");

    choiceButtonPanel.add(choice4);

    choice5 = new JButton("Choice 5");
    choice5.setBackground(Color.black);
    choice5.setForeground(Color.white);
    choice5.setFont(normalFont);
    choice5.setFocusPainted(false);
    choice5.addActionListener(choiceHandler);
    choice5.setActionCommand("c5");

    choiceButtonPanel.add(choice5);

    choice6 = new JButton("Choice 6");
    choice6.setBackground(Color.black);
    choice6.setForeground(Color.white);
    choice6.setFont(normalFont);
    choice6.setFocusPainted(false);
    choice6.addActionListener(choiceHandler);
    choice6.setActionCommand("c6");

    choiceButtonPanel.add(choice6);

    choice7 = new JButton("Choice 7");
    choice7.setBackground(Color.black);
    choice7.setForeground(Color.white);
    choice7.setFont(normalFont);
    choice7.setFocusPainted(false);
    choice7.addActionListener(choiceHandler);
    choice7.setActionCommand("c7");

    choiceButtonPanel.add(choice7);

    choice8 = new JButton("Choice 8");
    choice8.setBackground(Color.black);
    choice8.setForeground(Color.white);
    choice8.setFont(normalFont);
    choice8.setFocusPainted(false);
    choice8.addActionListener(choiceHandler);
    choice8.setActionCommand("c8");

    choiceButtonPanel.add(choice8);

    gbc.anchor = GridBagConstraints.PAGE_END;
    gbc.fill = GridBagConstraints.BOTH;

    gbc.gridx = 0;
    gbc.gridy = 0;

    con.add(playerPanel,gbc);

    gbc.fill = GridBagConstraints.HORIZONTAL;
    //gbc.ipadx = 750;
    gbc.ipady = 1000;
    gbc.gridwidth = 2;
    gbc.gridx = 1;
    gbc.gridy = 0;
    con.add(mainTextPanel,gbc);

    gbc.fill = GridBagConstraints.NONE;
    gbc.ipadx = 0;
    gbc.ipady = 0;
    gbc.gridx = 1;
    gbc.gridy = 5;
    con.add(choiceButtonPanel,gbc);

    hpLabel = new JLabel("HP: ");
    hpLabel.setFont(normalFont);
    hpLabel.setForeground(Color.white);

    hpLabelNumber = new JLabel();
    hpLabelNumber.setFont(normalFont);
    hpLabelNumber.setForeground(Color.white);

    weaponLabel = new JLabel("Weapon: ");
    weaponLabel.setFont(normalFont);
    weaponLabel.setForeground(Color.white);

    weaponLabelName = new JLabel();
    weaponLabelName.setFont(normalFont);
    weaponLabelName.setForeground(Color.white);

    playerPanel.add(hpLabel);
    playerPanel.add(hpLabelNumber);
    playerPanel.add(weaponLabel);
    playerPanel.add(weaponLabelName);
    mainTextPanel.add(mainTextArea, BorderLayout.PAGE_START);

    playerSetup();

}


public void playerSetup()
{
    playerHP = 15;
    weapon = "Fists";
    weaponLabelName.setText(weapon);
    hpLabelNumber.setText("" + playerHP);

    ForestEvents.townGate();
}

/*public void townGate()
{
    position = "towngate";

    mainTextArea.setText("You are at the gates of the town. A guard is standing in front of you. What do you do?");
    choice1.setText("Talk to the Guard");
    choice2.setText("Attack the Guard");
    choice3.setText("Leave");
    choice4.setText("");
}*/

public void talkGuard()
{
    position = "talkguard";

    mainTextArea.setText("Guard: Hello Stranger. I have never seen you before. I'm sorry but I cannot let you enter.");

    choice1.setText("Go Back");
    choice2.setText("");
    choice3.setText("");
    choice4.setText("");

}

public void attackGuard()
{
    position = "attackguard";

    mainTextArea.setText("Guard: HOW DARE YOU!\nThe guard fought back and hit you hard.\n(You received 3 damage)");
    playerHP -= 3;
    hpLabelNumber.setText("" + playerHP);

    choice1.setText("Go Back");
    choice2.setText("");
    choice3.setText("");
    choice4.setText("");

}

public void crossRoad()
{
    position = "crossroads";

    mainTextArea.setText("You are at the crossroad.\n Go south to go back to the town.");

    choice1.setText("Go North");
    choice2.setText("Go East");
    choice3.setText("Go South");
    choice4.setText("Go West");

}

public class ComponentHandler implements ComponentListener
{
    public void componentResized(ComponentEvent e)
    {
        Component c = (Component)e.getSource();
        window.setTitle("W: " + c.getWidth() + " H: " + c.getHeight());


    }

    @Override
    public void componentHidden(ComponentEvent e)
    {
        // TODO Auto-generated method stub

    }

    @Override
    public void componentMoved(ComponentEvent e)
    {

    }

    @Override
    public void componentShown(ComponentEvent e)
    {

    }
}

public class TitleScreenHandler implements ActionListener 
{
    public void actionPerformed(ActionEvent event)
    {
        createGameScreen();
    }
}

public class ChoiceHandler implements ActionListener
{
    public void actionPerformed(ActionEvent event)
    {
        String yourChoice = event.getActionCommand(); 

        switch (position) 
        {
            case "towngate":
                switch(yourChoice)
                {
                case "c1": 
                    talkGuard();
                    break;
                case "c2": 
                    attackGuard();
                    break;
                case "c3": 
                    crossRoad();
                    break;
                case "c4": 
                    break;
                }
                break;

            case "talkguard":
                switch(yourChoice)
                {
                case "c1":
                    ForestEvents.townGate();
                    break;
                }
                break;

            case "attackguard":
                switch(yourChoice)
                {
                case "c1":
                    ForestEvents.townGate();
                    break;  
                }
                break;

            case "crossroad":
                switch(yourChoice)
                {
                case"c1":
                    break;
                case"c2":
                    break;
                case"c3":
                    ForestEvents.townGate();
                    break;
                case"c4":
                    break;
                }
                break;


        }

    }

}

}

编辑：添加了剩余的代码，并将textarea添加到scrollpane，将scrollpane添加到Jpanel。现在，文本不会显示在面板中

import javax.swing.JTextArea;

public class ForestEvents
{
String pos;
int hp;

public ForestEvents()
{
    pos = Game.position;
    hp = Game.playerHP;
}

public static void townGate()
{
    Game.position = "towngate";

    Game.mainTextArea.setText("You are at the gates of the town. A guard is standing in front of you. What do you do? \na\nas\n\n\n\n\\n"
            + "\n\n\n\1\n1\n\n\n\n\n\\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n1\n1\n2\n2\n3\n4\n6");
    Game.choice1.setText("Talk to the Guard");
    Game.choice2.setText("Attack the Guard");
    Game.choice3.setText("Leave");
    Game.choice4.setText("");
}





}

正如Adeel在comments+1中所说的，您需要将JTextArea放入JScrollPane，然后使用GridBagLayout控制它。无需设置组件边界、首选大小等。如果要使用GridBagLayout，必须了解权重如何与填充和锚定一起工作。在下面的代码中，将gbc.fill HORIZONTAL更改为VERTICAL，并交换用于将滚动添加到窗口的权重，使其为weights x=0、y=1，或者将fill更改为两者并使两个权重都等于1。在这种情况下，您可以注释掉我在末尾添加的这个空JLabel。观察和学习

在代码中，您没有设置权重。所以，正如你可能已经猜到的，每样东西都有相同的重量。添加mainTextArea时，gbc.fill是水平的，没有权重，不在JScrollPane内-这就是它拉伸的原因。小心使用iPad

代码中的SSCCE注释

 public class DontStretchMyTextArea {

    public static void main(String[] args) {
        JFrame window = new JFrame();
        window.setSize(1440, 900);
        window.setTitle("W: " + window.getWidth() + " H: " + window.getHeight());
        window.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

        window.setLayout(new GridBagLayout());

        GridBagConstraints gbc = new GridBagConstraints();

        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.anchor = GridBagConstraints.NORTH;
        gbc.insets = new Insets(10, 10, 10, 10);

        JTextArea mainTextArea = new JTextArea( "This is the main text area" , 10 , 30 ); //here you can set how many rows/columns you want,
                                                                                          //but anyway GridBagLayout will recalculate size of component
                                                                                          //based on gbc.fill, weights and surrounding components
        //mainTextArea.setLayout(new GridLayout());
        mainTextArea.setLineWrap(true);
        mainTextArea.setWrapStyleWord(true);

        JScrollPane scroll = new JScrollPane(mainTextArea);
        scroll.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);

            JPanel panel = new JPanel();
            panel.setLayout(new GridBagLayout());
            GridBagConstraints panelGBC = new GridBagConstraints();

            panelGBC.weightx = 1;                    //I want to fill whole panel with JTextArea
            panelGBC.weighty = 1;                    //so both weights =1
            panelGBC.fill = GridBagConstraints.BOTH; //and fill is set to BOTH

            panel.add(scroll, panelGBC);
            panel.setBackground(Color.gray);//this shouldn't be visible


        gbc.weightx = 1;
        gbc.weighty = 0;
        window.add(panel, gbc);

        gbc.weightx = 1;
        gbc.weighty = 1;
        gbc.gridx++;
        window.add(new JLabel(), gbc); //GridBagLayout always needs component with both weights =1

        SwingUtilities.invokeLater(() -> { //we get our frame on EDT
            window.pack();
            window.setVisible(true);
        });
    }
}

---

您还可以将滚动直接添加到窗口。创建面板只是为了进行说明。

在JScrollPane中添加文本区域，然后将JScrollPane添加到JPanel中，而不是直接添加JTextarea，或者添加其余的类，这样我就可以编译您的代码，始终添加代码，然后可以复制和compiled@AdeelAhmed我添加了代码的其余部分，并且文本区域现在没有显示。感谢您澄清锚定和填充约束。我在使用GridBagLayout查看同一个网站，但当时有些事情还不清楚。我会和他们一起玩，以便更好地理解它。