java Swing JFileChooser 的使用

以你之姓@ 2022-08-18 11:46 160阅读 0赞

**本文总结了JFileChooser 的文件选择，文件保存，文件格式过滤三个功能的实现方法**

import java.awt.EventQueue;
    import java.awt.FlowLayout;
    import java.awt.HeadlessException;
    import java.awt.event.MouseAdapter;
    import java.awt.event.MouseEvent;
    import java.io.File;
    import java.io.IOException;
    
    import javax.swing.JButton;
    import javax.swing.JFileChooser;
    import javax.swing.JFrame;
    import javax.swing.JPanel;
    import javax.swing.border.EmptyBorder;
    import javax.swing.filechooser.FileNameExtensionFilter;
    
    public class TestOpen extends JFrame {
        
    
        private JPanel contentPane;
        private JFileChooser chooser;
    
        public static void main(String[] args) {
            EventQueue.invokeLater(new Runnable() {
                public void run() {
                    try {
                        TestOpen frame = new TestOpen();
                        frame.setVisible(true);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            });
        }
    
        /**
         * Create the frame.
         */
        public TestOpen() {
            chooser = new JFileChooser();
            setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            setBounds(100, 100, 450, 300);
            contentPane = new JPanel();
            contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
            setContentPane(contentPane);
    
            JButton btnOpen = new JButton("open file");
            btnOpen.addMouseListener(new MouseAdapter() {
                @Override
                public void mouseClicked(MouseEvent e) {
                    FileNameExtensionFilter filter  = new FileNameExtensionFilter
                            ("Allowd File", "txt","jar");//设置过滤器
                    chooser.setFileFilter(filter);
                    int value = chooser.showOpenDialog(TestOpen.this);
    
                    if (value == JFileChooser.APPROVE_OPTION) {
                        File file = chooser.getSelectedFile();
                        System.out.println(file.getAbsolutePath());
                    }
                }
            });
            contentPane.setLayout(new FlowLayout(FlowLayout.CENTER, 5, 5));
    
            JButton btnNewButton = new JButton("open dir");
            btnNewButton.addMouseListener(new MouseAdapter() {
                @Override
                public void mouseClicked(MouseEvent e) {
                    chooser.setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES);
                    chooser.setMultiSelectionEnabled(true);//设置可以多选
                    int value = chooser.showOpenDialog(TestOpen.this);
                    if (value == JFileChooser.APPROVE_OPTION) {
                        /*
                         * File file = chooser.getSelectedFile();
                         * System.out.println(file.getAbsolutePath());
                         */
    
                        File[] file = chooser.getSelectedFiles();
                        for (int i = 0; i < file.length; i++) {
                            System.err.println(file[i].getAbsolutePath());
                        }
                    }
                }
            });
            contentPane.add(btnNewButton);
            contentPane.add(btnOpen);
    
            JButton btnSave = new JButton("save");
            btnSave.addMouseListener(new MouseAdapter() {
    
                @Override
                public void mouseClicked(MouseEvent e) {
                    try {
                        JFileChooser chooser = new JFileChooser();
                        int value = chooser.showSaveDialog(TestOpen.this);
                        if (value == JFileChooser.APPROVE_OPTION) {
                            File newFile = chooser.getSelectedFile();
                            if (newFile.exists() == false) {
                                newFile.createNewFile();
                            }
                            // System.out.println(chooser.getSelectedFile().getAbsolutePath());
                        }
                    } catch (HeadlessException e1) {
                        e1.printStackTrace();
                    } catch (IOException e1) {
                        e1.printStackTrace();
                    }
                }
    
            });
            contentPane.add(btnSave);
        }
    
    }