版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/yerenyuan_pku/article/details/84868755
文件(夹)搜索
在文本框中输入目录，点击“确定”按钮，将该目录中的文件与文件夹名称列在下面的文本区域中，如图所示。
package cn.liayun.swing;
import java.awt.BorderLayout;
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JButton;
import javax.swing.JTextField;
import javax.swing.JTextArea;
import javax.swing.JScrollBar;
import javax.swing.JTabbedPane;
import javax.swing.JScrollPane;
import java.awt.event.ActionListener;
import java.io.File;
import java.awt.event.ActionEvent;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
public class MyWindow extends JFrame {
private static final String LINE_SEPARATOR = System.getProperty("line.separator");
private JPanel contentPane;
private JTextField textField;
private JTextArea textArea;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
MyWindow frame = new MyWindow();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public MyWindow() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 851, 578);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
JButton btnNewButton = new JButton("\u786E\u5B9A");
btnNewButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
// System.out.println("hello button");
btnNewButtonActionPerformed(evt);
}
});
btnNewButton.setBounds(671, 31, 105, 43);
contentPane.add(btnNewButton);
textField = new JTextField();
textField.addKeyListener(new KeyAdapter() {
@Override
public void keyPressed(KeyEvent evt) {
textFieldKeyPressed(evt);
}
});
textField.setBounds(27, 31, 630, 43);
contentPane.add(textField);
textField.setColumns(10);
JScrollPane scrollPane = new JScrollPane();
scrollPane.setBounds(27, 97, 748, 401);
contentPane.add(scrollPane);
textArea = new JTextArea();
scrollPane.setViewportView(textArea);
}
protected void textFieldKeyPressed(KeyEvent evt) {
if (evt.getKeyCode() == KeyEvent.VK_ENTER) {
showDir();
}
}
protected void btnNewButtonActionPerformed(ActionEvent evt) {
// System.out.println("hello button");
showDir();
}
private void showDir() {
//通过在文本框输入具体的目录，将目录中的当前文件或者文件夹的名称列出到文本区域中
/*
* 思路：
* 1，获取文本框中的路径
* 2，将路径封装成File对象，list()方法
* 3，将list()列表中的内容展现在文本区域中
*/
//1，获取路径，通过文本框对象来完成
String str_dir = textField.getText();
//2，将字符串路径封装成File对象
File dir = new File(str_dir);
//判断健壮性
if (dir.exists() && dir.isDirectory()) {
//清空文本区域
textArea.setText("");
//3，获取文件名称列表
String[] names = dir.list();
for (String name : names) {
//4，将名字显示到文本区域
textArea.append(name + LINE_SEPARATOR);
}
}
}
}
模仿Windows的记事本程序
模仿Windows的记事本（notepad.exe）程序完成文件的打开、退出的操作，如下图所示。
package cn.liayun.swing;
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.border.EmptyBorder;
import javax.swing.filechooser.FileNameExtensionFilter;
import cn.liayun.separator.Separator;
public class MyMenu extends JFrame {
// private static final String LINE_SEPARATOR = System.getProperty("line.separator");
private JPanel contentPane;
private JTextArea textArea;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
MyMenu frame = new MyMenu();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public MyMenu() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 875, 647);
JMenuBar menuBar = new JMenuBar();
menuBar.setToolTipText("");
setJMenuBar(menuBar);
JMenu mnNewMenu = new JMenu("\u6587\u4EF6");
menuBar.add(mnNewMenu);
JMenuItem menuItem = new JMenuItem("\u6253\u5F00");
menuItem.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
menuItemActionPerformed(evt);
}
});
mnNewMenu.add(menuItem);
JMenuItem menuItem_1 = new JMenuItem("\u9000\u51FA");
menuItem_1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
menuItem_1ActionPerformed(evt);
}
});
mnNewMenu.add(menuItem_1);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
contentPane.setLayout(new BorderLayout(0, 0));
setContentPane(contentPane);
JScrollPane scrollPane = new JScrollPane();
contentPane.add(scrollPane, BorderLayout.CENTER);
textArea = new JTextArea();
scrollPane.setViewportView(textArea);
}
protected void menuItemActionPerformed(ActionEvent evt) {
//创建一个文件选择器
JFileChooser chooser = new JFileChooser();
//创建一个文件扩展名过滤器
FileNameExtensionFilter filter = new FileNameExtensionFilter(
"Java & Txt", "java", "txt");
//给文件选择器设置过滤器
chooser.setFileFilter(filter);
//文件选择器调用了显示选择文件对话框，并获取该对话框的返回值
int returnVal = chooser.showOpenDialog(this);
//判断返回值
if(returnVal == JFileChooser.APPROVE_OPTION) {
// System.out.println("You chose to open this file: " +
// chooser.getSelectedFile().getName());
//清空文本区域
textArea.setText("");
//获取选择的目录
File file = chooser.getSelectedFile();
// System.out.println(file.getAbsolutePath());
//读取文件
try {
BufferedReader bufr = new BufferedReader(new FileReader(file));
String line = null;
while ((line = bufr.readLine()) != null) {
textArea.append(line + Separator.LINE_SEPARATOR);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
protected void menuItem_1ActionPerformed(ActionEvent evt) {
System.exit(0);
}
}
