JTextArea比较详细的使用

import java.awt.BorderLayout;

import java.awt.Container;

import java.awt.Graphics;

import java.awt.Image;

import javax.swing.GrayFilter;

import javax.swing.ImageIcon;

import javax.swing.JFrame;

import javax.swing.JLabel;

import javax.swing.JPanel;

import javax.swing.JScrollPane;

import javax.swing.JTextArea;

/***

* 给JTextArea添加背景色

* @author Administrator

*

*/

public class BackgroundSample {

public static void main(String args[]) {

JFrame frame = new JFrame("Background Example");

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

final ImageIcon imageIcon = new ImageIcon("draft.gif");

JTextArea textArea = new JTextArea() {

Image image = imageIcon.getImage();

Image grayImage = GrayFilter.createDisabledImage(image);

{

setOpaque(false);

}

public void paint(Graphics g) {

g.drawImage(grayImage, 0, 0, this);

super.paint(g);

}

};

JScrollPane scrollPane = new JScrollPane(textArea);

Container content = frame.getContentPane();

content.add(scrollPane, BorderLayout.CENTER);

frame.setSize(250, 250);

frame.setVisible(true);

}

}

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JPanel;

import javax.swing.JScrollPane;

import javax.swing.JTextArea;

/**

* 处理JTextArea的换行操作

* @author Administrator

*

*/

public class TextAreaFrame extends JFrame implements ActionListener{

private JButton insertButton = new JButton("Insert");

private JButton wrapButton = new JButton("Wrap");

private JButton noWrapButton = new JButton("No wrap");

private JTextArea textArea = new JTextArea(8, 40);

private JScrollPane scrollPane = new JScrollPane(textArea);

public TextAreaFrame() {

JPanel p = new JPanel();

p.add(insertButton);

insertButton.addActionListener(this);

p.add(wrapButton);

wrapButton.addActionListener(this);

p.add(noWrapButton);

noWrapButton.addActionListener(this);

getContentPane().add(p, "South");

getContentPane().add(scrollPane, "Center");

setTitle("TextAreaTest");

setSize(300, 300);

addWindowListener(new WindowAdapter() {

public void windowClosing(WindowEvent e) {

System.exit(0);

}

});

}

public void actionPerformed(ActionEvent evt) {

Object source = evt.getSource();

if (source == insertButton)

textArea

.append("textArea The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog.");

else if (source == wrapButton) {

//常用方法有对两个方法介绍

textArea.setWrapStyleWord(true);

textArea.setLineWrap(true);

scrollPane.validate();

} else if (source == noWrapButton) {

textArea.setLineWrap(false);

textArea.setWrapStyleWord(false);

scrollPane.validate();

}

}

public static void main(String[] args) {

JFrame f = new TextAreaFrame();

f.show();

}

}

import java.awt.BorderLayout;

import java.awt.Container;

import java.util.Hashtable;

import javax.swing.Action;

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.text.DefaultEditorKit;

/**

* 使用按钮做剪切、复制、粘贴操作

* @author Administrator

*

*/

public class CutPasteSample {

public static void main(String args[]) {

JFrame frame = new JFrame("Cut/Paste Example");

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

Container content = frame.getContentPane();

JTextField textField = new JTextField();

JTextArea textArea = new JTextArea();

JScrollPane scrollPane = new JScrollPane(textArea);

content.add(textField, BorderLayout.NORTH);

content.add(scrollPane, BorderLayout.CENTER);

Action actions[] = textField.getActions();

Action cutAction = TextUtilities.findAction(actions,

DefaultEditorKit.cutAction);

Action copyAction = TextUtilities.findAction(actions,

DefaultEditorKit.copyAction);

Action pasteAction = TextUtilities.findAction(actions,

DefaultEditorKit.pasteAction);

JPanel panel = new JPanel();

content.add(panel, BorderLayout.SOUTH);

JButton cutButton = new JButton(cutAction);

cutButton.setText("Cut");

panel.add(cutButton);

JButton copyButton = new JButton(copyAction);

copyButton.setText("Copy");

panel.add(copyButton);

JButton pasteButton = new JButton(pasteAction);

pasteButton.setText("Paste");

panel.add(pasteButton);

frame.setSize(250, 250);

frame.setVisible(true);

}

}

class TextUtilities {

private TextUtilities() {

}

public static Action findAction(Action actions[], String key) {

Hashtable commands = new Hashtable();

for (int i = 0; i < actions.length; i++) {

Action action = actions[i];

commands.put(action.getValue(Action.NAME), action);

}

return (Action) commands.get(key);

}

}