当输入的内容太多时，我的JTextArea怎么不会自动出现滚动条呢？

import javax.swing.UIManager;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class Application1 {
  private boolean packFrame = false;

  //Construct the application
  public Application1() {
    Frame1 frame = new Frame1();
    //Validate frames that have preset sizes
    //Pack frames that have useful preferred size info, e.g. from their layout
    if (packFrame) {
      frame.pack();
    }
    else {
      frame.validate();
    }
    //Center the window
    Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
    Dimension frameSize = frame.getSize();
    if (frameSize.height > screenSize.height) {
      frameSize.height = screenSize.height;
    }
    if (frameSize.width > screenSize.width) {
      frameSize.width = screenSize.width;
    }
    frame.setLocation((screenSize.width - frameSize.width) / 2, (screenSize.height - frameSize.height) / 2);
    frame.setVisible(true);
  }
  //Main method
  public static void main(String[] args) {
    try {
      UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
    }
    catch(Exception e) {
      e.printStackTrace();
    }
    new Application1();
  }
}
class Frame1 extends JFrame {
  private JPanel contentPane;
  private BorderLayout borderLayout1 = new BorderLayout();
  private JTextArea jTextArea1 = new JTextArea();
  private JPanel jPanel1 = new JPanel();
  private JButton jButton1 = new JButton();

  //Construct the frame
  public Frame1() {
    enableEvents(AWTEvent.WINDOW_EVENT_MASK);
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
  }
  //Component initialization
  private void jbInit() throws Exception  {
    //setIconImage(Toolkit.getDefaultToolkit().createImage(Frame1.class.getResource("[Your Icon]")));
    contentPane = (JPanel) this.getContentPane();
    jTextArea1.setText("jTextArea1");
    jTextArea1.setLineWrap(true);
    jTextArea1.setRows(2);
    jTextArea1.setWrapStyleWord(true);
    contentPane.setLayout(borderLayout1);
    this.setSize(new Dimension(400, 300));
    this.setTitle("Frame Title");
    jButton1.setText("jButton1");
    contentPane.add(jTextArea1, BorderLayout.CENTER);
    contentPane.add(jPanel1, BorderLayout.NORTH);
    jPanel1.add(jButton1, null);
  }
  //Overridden so we can exit when window is closed
  protected void processWindowEvent(WindowEvent e) {
    super.processWindowEvent(e);
    if (e.getID() == WindowEvent.WINDOW_CLOSING) {
      System.exit(0);
    }
  }
}
当输入的内容太多时，我的JTextArea怎么不会自动出现滚动条呢？

7 个解决方案

#1

先加JScrollpanel，在把JTextArea 家道JScrollPanel 上

#2

同意.

#3

jScrollPane1.getViewport().add(jTextArea1, null);

#4

呵呵,同意....

#5

把你代码中的这一句：
contentPane.add(jTextArea1, BorderLayout.CENTER);
改为：
contentPane.add(new JScroollPanel(jTextArea1), BorderLayout.CENTER);
即可。

#6

我同意henry_cn(学问：要学，要问！) 老兄的看法。

#7

JScroolPanel jScrool = new JScroolPanel(jTextArea1);
contentPane.add(jScrool, BorderLayout.CENTER);

#1