Java JScrollpane - JTextPane - Log4J AppenderSkeleton 水平滚动问题

Question

我有一个带有 JTextPane 的 swing gui，用于从底层应用程序输出日志。我的问题是，在初始化 gui 并记录第一个日志条目后，滚动条将“禁用”，直到我触发操作。下一个日志条目后，水平滚动条“出现”。

第二个问题是有时日志语句的长度是1030个字符。但水平滚动最大为 606 个字符。如果我从 JTextPane 复制文本，我会得到洞(1030char)文本。

我尝试在 MainFrame 中 logTxtArea.setText("... -> 1030 chars..."); <<- 滚动条按预期工作，并且还会显示日志语句。

这是我在大型机中的 JTestPane 初始化代码

private static JTextPane logTxtArea = new JTextPane();
......

        logTxtArea.setEditable(false);
        logTxtArea.setEditorKit(new NoWrapEditorKit());
        JScrollPane logScroller = new JScrollPane(logTxtArea);
        logScroller.setFont(new Font("Segoe UI", Font.PLAIN, 12));
        logScroller.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
        logScroller.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS);
        gbc = new GridBagConstraints();
        gbc.anchor = GridBagConstraints.SOUTHWEST;
        gbc.fill = GridBagConstraints.BOTH;
        gbc.gridwidth = 1;
        gbc.gridheight = 8;
        gbc.gridx = 0;
        gbc.gridy = 0;
        gbc.insets = new Insets(10, 15, 10, 5);
        gbc.weightx = 1;
        gbc.weighty = 1;
        main.add(logScroller, gbc);

还有我的 NoWrapEditorKit ->

public class TextAreaAppender extends AppenderSkeleton {

    private static Style style;

    protected void append(LoggingEvent event) {
        this.layout = new PatternLayout("%d - %m%n");
        String msg = this.layout.format(event);
        JTextPane textArea = MainFrame.getLogTxtArea();
        Color color = Color.BLACK;

        if (event.getLevel() == Level.INFO) {
            color = Color.BLUE;
        } else if (event.getLevel() == Level.WARN || event.getLevel() == Level.ERROR || event.getLevel() == Level.FATAL) {
            color = Color.RED;
        }

        if (msg.contains("INFO:")) {
            color = Color.MAGENTA;
        }

        appendToPane(textArea, msg, color);
        MainFrame.getLogTxtArea().setCaretPosition(MainFrame.getLogTxtArea().getDocument().getLength());
    }

    public void close() {
    }

    public boolean requiresLayout() {
        return false;
    }

    private void appendToPane(JTextPane tp, String msg, Color c) {
        int len = tp.getDocument().getLength();
        if (style == null) {
            style = tp.addStyle("", null);
        }

        try {
            StyleConstants.setForeground(style, c);
            tp.getStyledDocument().insertString(len, msg, style);
        } catch (BadLocationException e) {
            e.printStackTrace();
        }
    }
}

所以目标是每行获取一条没有换行符的日志语句。此外，很长的语句(1030 个字符)应该完整显示。

谢谢!

更新

这是一个简短的示例:

public class TextFrame extends JFrame {

    private JTextPane txtPane;
    private Style style;

    public TextFrame() {
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setResizable(true);
        this.setMinimumSize(new Dimension(600, 400));
        this.setPreferredSize(new Dimension(900, 600));

        txtPane = new JTextPane()
        {
            public boolean getScrollableTracksViewportWidth()
            {
                return getUI().getPreferredSize(this).width
                        <= getParent().getSize().width;
            }
        };
        txtPane.setEditable(false);
        JScrollPane logScroller = new JScrollPane(txtPane);
        logScroller.setFont(new Font("Segoe UI", Font.PLAIN, 12));
        logScroller.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
        logScroller.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS);
        this.add(logScroller);

        append("Short text" + System.lineSeparator(), Color.BLACK);
        append("1030 char text - 1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz12345"  + System.lineSeparator(), Color.BLACK);
        append("2000 char text - 1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz123"  + System.lineSeparator(), Color.BLACK);

        this.pack();
        this.setLocationRelativeTo(null);
        this.setVisible(true);
    }

    private void append(String message, Color color) {

        int len = txtPane.getDocument().getLength();
        if (style == null) {
            style = txtPane.addStyle("", null);
        }

        try {
            StyleConstants.setForeground(style, color);
            txtPane.getStyledDocument().insertString(len, message, style);
        } catch (BadLocationException e) {
            e.printStackTrace();
        }

        //scroll to bottom
        txtPane.setCaretPosition(txtPane.getDocument().getLength());
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException e) {
                    e.printStackTrace();
                } catch (InstantiationException e) {
                    e.printStackTrace();
                } catch (IllegalAccessException e) {
                    e.printStackTrace();
                } catch (UnsupportedLookAndFeelException e) {
                    e.printStackTrace();
                }
                new TextFrame();
            }
        });
    }

}

Answer 1

让它工作。解决方案是将 JTextPane 添加到 JPanel。将 JPanel 的布局设置为 BoarderLayout。我发现滚动速度卡住了，所以我设置了滚动速度。

这是最终的解决方案:

public class TextFrame extends JFrame {

    private JTextPane txtPane = new JTextPane();
    private Style style;

    public TextFrame() {
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setResizable(true);
        this.setMinimumSize(new Dimension(600, 400));
        this.setPreferredSize(new Dimension(900, 600));


        txtPane.setFont(new Font("Segoe UI", Font.PLAIN, 20));
        txtPane.setEditable(false);

        JPanel panel = new JPanel();
        panel.setLayout(new BorderLayout());
        panel.add(txtPane);

        JScrollPane logScroller = new JScrollPane(panel);
        logScroller.getVerticalScrollBar().setUnitIncrement(16);
        logScroller.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
        logScroller.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS);
        this.add(logScroller);

        //txtPane.setText("TEST text in this line..");
        append("Short text" + System.lineSeparator(), Color.BLACK);
        append("1030 char text - 1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz12345"  + System.lineSeparator(), Color.BLACK);
        append("2000 char text - 1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnopqrstuvwxyz123"  + System.lineSeparator(), Color.BLACK);

        this.pack();
        this.setLocationRelativeTo(null);
        this.setVisible(true);
    }

    private void append(String message, Color color) {

        int len = txtPane.getDocument().getLength();
        if (style == null) {
            style = txtPane.addStyle("", null);
        }

        try {
            StyleConstants.setForeground(style, color);
            txtPane.getStyledDocument().insertString(len, message, style);
        } catch (BadLocationException e) {
            e.printStackTrace();
        }

        //scroll to bottom
        //txtPane.setCaretPosition(txtPane.getDocument().getLength());
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException e) {
                    e.printStackTrace();
                } catch (InstantiationException e) {
                    e.printStackTrace();
                } catch (IllegalAccessException e) {
                    e.printStackTrace();
                } catch (UnsupportedLookAndFeelException e) {
                    e.printStackTrace();
                }
                new TextFrame();
            }
        });
    }

}