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设计思路

1. 包名定义与窗口创建

我将使用Java Swing框架来构建一个文件浏览器应用程序。首先，定义包名并创建主窗口。通过import java.awt.Container;和import java.awt.FlowLayout;等必要的包来实现布局。在MyDemo类中，创建一个带标题的窗口，并设置其默认关闭行为为退出程序。

package my;
import java.awt.Container;
import java.awt.FlowLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class MyDemo {
    private static void createGUI() {
        JFrame frame = new MyFrame("目录列表");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(400, 300);
        frame.setVisible(true);
    }
    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createGUI();
            }
        });
    }
}

2. 文件浏览器实现

接下来，定义MyFrame类，继承自JFrame。在构造函数中，创建一个JPanel作为内容面板，并设置适当布局。通过DefaultListModel和JList来展示文件目录。为了实现右键菜单功能，使用了MouseAdapter和JPopupMenu。

package my;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.io.File;
import javax.swing.DefaultListModel;
import javax.swing.JCheckBoxMenuItem;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.JScrollPane;
import javax.swing.ListModel;
public class MyFrame extends JFrame {
    public MyFrame(String title) {
        super(title);
        JPanel root = new JPanel();
        this.setContentPane(root);
        root.setLayout(new BorderLayout());
        JList list = new JList();
        list.setModel(new DefaultListModel());
        list.setVisibleRowCount(-1);
        list.setLayoutOrientation(JList.HORIZONTAL_WRAP);
        list.setCellRenderer(new FileIconCellRenderer());
        list.addMouseListener(new FileMouseListener());
        JScrollPane listScrollPane = new JScrollPane(list);
        root.add(listScrollPane, BorderLayout.CENTER);
        loadDir(new File("c:/"));
    }
    private void loadDir(File dir) {
        File[] files = dir.listFiles();
        if (files != null) {
            for (File f : files) {
                FileListItem item = new FileListItem(f);
                ((DefaultListModel) list.getModel()).addElement(item);
                list.revalidate();
            }
        }
    }
    private void showContextMenu(MouseEvent e) {
        int index = list.locationToIndex(e.getPoint());
        if (index >= 0) {
            list.setSelectedIndex(index);
        }
        JPopupMenu menu = new JPopupMenu();
        JMenuItem listModeCmd = new JCheckBoxMenuItem("列表模式");
        listModeCmd.setActionCommand("listMode");
        listModeCmd.setSelected(!iconMode);
        listModeCmd.addActionListener(menuActionListener);
        menu.add(listModeCmd);
        JMenuItem iconModeCmd = new JCheckBoxMenuItem("图标模式");
        iconModeCmd.setActionCommand("iconMode");
        iconModeCmd.setSelected(iconMode);
        iconModeCmd.addActionListener(menuActionListener);
        menu.add(iconModeCmd);
        menu.show(e.getComponent(), e.getX(), e.getY());
    }
    private class FileMouseListener extends MouseAdapter {
        public void mouseClicked(MouseEvent e) {
            if (e.getButton() == MouseEvent.BUTTONvouit) {
                showContextMenu(e);
            }
        }
    }
    private class MenuActionListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            String action = e.getActionCommand();
            if (action.equals("listMode")) {
                iconMode = false;
                list.setLayoutOrientation(JList.VERTICAL);
                list.setCellRenderer(new FileListCellRenderer());
            } else if (action.equals("iconMode")) {
                iconMode = true;
                list.setLayoutOrientation(JList.HORIZONTAL_WRAP);
                list.setCellRenderer(new FileIconCellRenderer());
            }
        }
    }
    private boolean iconMode = true;
}

3. 文件属性定义

定义FileListItem类，用于存储文件的基本属性。通过File类获取文件信息，并设置日期格式来显示最后修改时间。

package my;
import java.io.File;
import java.text.SimpleDateFormat;
public class FileListItem {
    public String name;
    public File file;
    public boolean isDir;
    public String lastModified;
    public FileListItem(File f) {
        this.file = f;
        this.name = f.getName();
        this.isDir = f.isDirectory();
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        this.lastModified = sdf.format(f.lastModified());
    }
}

4. 文件图标显示

自定义FileIconCellRenderer类来实现文件或目录的图标显示。通过JsImageView和JLabel布局来展示图标和文件名。

package my;
import java.awt.Color;
import java.awt.Component;
import java.awt.Font;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.ListCellRenderer;
import js.swing.JsColumnLayout;
import js.swing.JsImageView;
import js.swing.JsPanel;
import js.swing.JsRowLayout;
public class FileIconCellRenderer extends JsPanel implements ListCellRenderer {
    private JsImageView thumbField = new JsImageView();
    private JLabel nameField = new JLabel();
    private Image icFolder, icFile;
    public FileIconCellRenderer() {
        this.setLayout(new JsColumnLayout(10));
        this.padding(10);
        this.perferredSize(80, 110);
        this.add(thumbField, "1w");
        this.add(nameField, "30px");
        try {
            icFolder = ImageIO.read(getClass().getResource("/icon/ic_folder_64.png"));
            icFile = ImageIO.read(getClass().getResource("/icon/ic_file_64.png"));
        } catch (IOException e) {
            e.printStackTrace();
        }
        thumbField.setBgColor(new Color(255, 255, 255, 0));
        Font textFont = nameField.getFont().deriveFont(Font.PLAIN);
        nameField.setFont(textFont);
        nameField.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
    }
    @Override
    public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
        FileListItem item = (FileListItem) value;
        if (item.isDir()) {
            thumbField.setImage(icFolder);
        } else {
            thumbField.setImage(icFile);
        }
        nameField.setText(item.name);
        if (isSelected) {
            this.setBackground(list.getSelectionBackground());
            this.setForeground(list.getSelectionForeground());
        } else {
            this.setBackground(list.getBackground());
            this.setForeground(list.getForeground());
        }
        return this;
    }
}

5. 列表显示

同样地，定义FileListCellRenderer类来实现列表显示，展示图标、文件名和最后修改时间。

package my;
import java.awt.Component;
import java.awt.Font;
import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.ListCellRenderer;
import js.swing.JsPanel;
import js.swing.JsRowLayout;
public class FileListCellRenderer extends JsPanel implements ListCellRenderer {
    private JLabel iconField = new JLabel();
    private JLabel nameField = new JLabel();
    private JLabel timeField = new JLabel();
    private ImageIcon icFolder, icFile;
    public FileListCellRenderer() {
        this.setLayout(new JsRowLayout());
        this.padding(2);
        this.perferredHeight(30);
        this.add(iconField, "20px");
        this.add(nameField, "1w");
        this.add(timeField, "150px");
        try {
            icFolder = new ImageIcon(getClass().getResource("/icon/ic_folder.png"));
            icFile = new ImageIcon(getClass().getResource("/icon/ic_file.png"));
        } catch (IOException e) {
            e.printStackTrace();
        }
        Font textFont = timeField.getFont().deriveFont(Font.PLAIN);
        nameField.setFont(textFont);
        timeField.setFont(textFont);
    }
    @Override
    public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
        FileListItem item = (FileListItem) value;
        if (item.isDir()) {
            iconField.setIcon(icFolder);
        } else {
            iconField.setIcon(icFile);
        }
        nameField.setText(item.name);
        timeField.setText(item.lastModified);
        if (isSelected) {
            this.setBackground(list.getSelectionBackground());
            this.setForeground(list.getSelectionForeground());
        } else {
            this.setBackground(list.getBackground());
            this.setForeground(list.getForeground());
        }
        return this;
    }
}