java - 如何使用 RTFEditorKit 读取纯文本文件？

Question

我正在创建一个简单的写字板编辑器应用程序。我正在使用 JTextPane。我添加了代码以使用 RTFEditorKit 读取“.rtf”文件。初始化代码:

RTFEditorKit rtfKit = new RTFEditorKit();
JTextPane textPane = new JTextPane();
textPane.setEditorKit(rtfKit);

现在我需要使用“RTFEditorKit”将纯文本文件“.txt”读取到同一个 JTextPane 中，这样我就可以在同一个应用程序中查看纯文本文件和 rtf 文件。我怎样才能做到这一点？

我的应用程序最少代码:

import static java.awt.event.InputEvent.CTRL_DOWN_MASK;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.InputStream;

import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.KeyStroke;
import javax.swing.UIManager;
import javax.swing.filechooser.FileNameExtensionFilter;
import javax.swing.text.Document;
import javax.swing.text.MutableAttributeSet;
import javax.swing.text.Style;
import javax.swing.text.StyleContext;
import javax.swing.text.StyledDocument;
import javax.swing.text.rtf.RTFEditorKit;

public class MyNotepad implements ActionListener {
    public JFrame frame;
    public JPanel panel;
    public JTextPane textPane;
    public RTFEditorKit rtf;
    public StyleContext styleContext;
    public Document document;
    public JScrollPane scrollPane;
    public JMenuBar menuBar;
    public JMenu fileMenu;
    public JMenuItem newSubMenu;
    public JMenuItem openSubMenu;
    public JFileChooser fc;
    public boolean openFileExtFlag = true;
    public boolean saveFileExtFlag = true;
    public File openFile;
    public File saveFile;
    public boolean saveWindowTitle = false;
    public boolean openFileFlag;
    public boolean saveFileFlag;
    public boolean saved = true;
    public boolean dontSaveOption;
    public BufferedReader br;
    public boolean saveForNewOpenExitListener;
    public boolean saveAsFlag;
    public int returnVal;
    public String filePath;
    public boolean flagForOpenListener;
    public StyledDocument styledDocument;
    public Style defaultStyle;
    public MutableAttributeSet mas;

    public MyNotepad() {
        try {
            UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
        } catch (Exception e) {
            e.printStackTrace();
        }
        frame = new JFrame("My Notepad");
        panel = new JPanel(new BorderLayout());                                                      

        rtf = new RTFEditorKit();
        textPane = new JTextPane();
        textPane.setEditorKit(rtf);
        textPane.setMargin(new Insets(10,5,5,5));
        styleContext = new StyleContext();
        mas = textPane.getInputAttributes();
        styledDocument = textPane.getStyledDocument();
        textPane.setDocument(styledDocument);

        scrollPane = new JScrollPane();
        scrollPane.getViewport().add(textPane);
        menuBar = new JMenuBar();

        fileMenu = new JMenu("File");
        fileMenu.setMnemonic(KeyEvent.VK_F);
        newSubMenu = new JMenuItem("New");
        newSubMenu.setAccelerator(KeyStroke.getKeyStroke('N', CTRL_DOWN_MASK));
        openSubMenu = new JMenuItem("Open...");
        openSubMenu.setAccelerator(KeyStroke.getKeyStroke('O', CTRL_DOWN_MASK));

        defaultStyle = StyleContext.getDefaultStyleContext().getStyle(StyleContext.DEFAULT_STYLE);
        fc= new JFileChooser();

        openSubMenu.addActionListener(this);
        newSubMenu.addActionListener(this);

        scrollPane.setPreferredSize(new Dimension(700,500));

        fileMenu.add(newSubMenu);
        fileMenu.add(openSubMenu);

        menuBar.add(fileMenu);

        textPane.setFont(new Font("Arial", Font.PLAIN, 12));
        panel.add(scrollPane, BorderLayout.CENTER);
        panel.add(new JLabel(" "), BorderLayout.EAST);
        panel.add(new JLabel(" "), BorderLayout.WEST);
        panel.add(new JLabel(" "), BorderLayout.SOUTH);

        frame.setJMenuBar(menuBar);
        frame.add(panel);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setMinimumSize(new Dimension(900,200));
        frame.pack();
        textPane.requestFocus();                                                
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        new MyNotepad();
    }

    public void actionPerformed(ActionEvent ae) {
        if ((ae.getSource() == openSubMenu)) {      
            openActionListener();
        } 
    }

    public boolean openActionListener() {
        if (openFileExtFlag && saveFileExtFlag) {
            fc.setAcceptAllFileFilterUsed(false);
            fc.addChoosableFileFilter(new FileNameExtensionFilter("Rich Text File (*.rtf)", "rtf"));
            fc.addChoosableFileFilter(new FileNameExtensionFilter("Text File (*.txt)", "txt"));
            openFileExtFlag = false;
        }

        do {
            returnVal = fc.showOpenDialog(frame);                               
            if (returnVal == JFileChooser.APPROVE_OPTION) {
                openFile = fc.getSelectedFile();
                filePath = openFile.getPath();
                if (openFile.exists()) {
                    break;
                }
                JOptionPane.showMessageDialog(frame, "File not found, please verify the file name and the path", "Cannot open", JOptionPane.OK_OPTION);
            } else {
                return false;
            }
        } while (true);


        try {
            System.out.println("---opening document...");

            textPane.setText("");
            InputStream in = new FileInputStream(filePath);
            System.out.println("Opening file - " + filePath);

            if (filePath.endsWith(".rtf")) {
                rtf.read(in, textPane.getDocument(), 0);
                in.close();
            } else if (filePath.endsWith(".txt")) {
                textPane = new JTextPane();
                FileReader fileReader = new FileReader(filePath);
                textPane.read(fileReader, openFile);
                fileReader.close();
            }
            textPane.requestFocus();
            textPane.setCaretPosition(0);
            frame.setTitle("My Notepad  " + "- " + filePath);
            System.out.println("----File opened successfully");
        } catch (Exception e) {
            JOptionPane.showMessageDialog(frame, "Cannot open, Invalid RTF file", "Cannot open", JOptionPane.OK_OPTION);
        }
        return true;
    }
}

Answer 1

textPane = new JTextPane();
FileReader fileReader = new FileReader(filePath);
textPane.read(fileReader, openFile);
fileReader.close();

您正在创建一个永远不会添加到 UI 的新 JTextPane，并且文本添加到这个 textPane 而不是您在 UI 中看到的那个...

只需删除行:textPane = new JTextPane();

抱歉回答晚了。