如何在Java Swing TextArea中更改突出显示颜色？ 并且，更改与突出显示位置相对应的文本的开头

Question

问题1：通过使用defaulthighlighter，我可以使聚焦线变为蓝色。 现在，我想将其更改为其他颜色。 有人知道如何更改此参数吗？ - - 解决了

问题2：pos是我要突出显示的子字符串的开始索引。 我使用setCaretPosition（pos）; 更新显示内容。 但是它总是出现在窗口的底部。 我想把它放在顶部。 谁能告诉我该如何处理？

我使用一个演示来展示我的问题：

import java.awt.Color;
import java.net.MalformedURLException;

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.SwingUtilities;
import javax.swing.text.BadLocationException;
import javax.swing.text.DefaultHighlighter;

public class Test {
    public static void main(final String[] args) throws MalformedURLException {
        SwingUtilities.invokeLater(new Runnable() {

        @Override
        public void run() {
            try {
                init();
            } catch (BadLocationException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

        }
    });
}

private static void init() throws BadLocationException {
    JFrame frame = new JFrame();
    final JTextArea textArea = new JTextArea();
    JScrollPane pane = new JScrollPane(textArea);
    textArea.setText("Something. Something else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Samething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Sbmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Scmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Sdmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Semething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Sfmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Sgmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n");
    textArea.setSelectionColor(Color.RED);
    frame.add(pane);
    frame.setSize(300, 120);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setVisible(true);

    String turnToString2 = "Sdmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla";
    int pos2 = textArea.getText().indexOf(turnToString2);
    textArea.getHighlighter().addHighlight(pos2,
            pos2 + turnToString2.length(),
            new DefaultHighlighter.DefaultHighlightPainter(Color.yellow));
    textArea.setCaretPosition(pos2);

结果是：

我希望它位于屏幕的右上方，但是在这段代码中，它显示在滚动窗格的底部。 有人知道如何更改吗？ 谢谢。

Answer 1

您可以实现此操作，尽管不是直接实现，因为您必须保存对添加到上述行的“ Highlight的引用，因此您必须遍历所有“突出显示”以删除所需的突出显示，请看一下程序可能会帮助您实现自己的愿望：

最新编辑：新代码，已删除的一些错误和类似添加了与设置购物车位置有关的功能的零件

import java.awt.*;
import java.awt.event.*;
import java.util.Map;
import java.util.HashMap;
import javax.swing.*;
import javax.swing.text.*;

public class TextHighlight
{
    private JTextArea tarea;
    private JComboBox cbox;
    private JTextField lineField;
    private String[] colourNames = {"RED", "ORANGE", "CYAN"};

    private Highlighter.HighlightPainter redPainter;
    private Highlighter.HighlightPainter orangePainter;
    private Highlighter.HighlightPainter cyanPainter;   

    private int firstUpdateIndex;
    private int counter;

    private Map<Integer, Highlighter.Highlight> highlights = new HashMap<Integer, Highlighter.Highlight>();

    public TextHighlight()
    {
        redPainter = new DefaultHighlighter.DefaultHighlightPainter(Color.RED);
        orangePainter = new DefaultHighlighter.DefaultHighlightPainter(Color.ORANGE);
        cyanPainter = new DefaultHighlighter.DefaultHighlightPainter(Color.CYAN);

        firstUpdateIndex = -1;
        counter = 0;
    }

    private void createAndDisplayGUI()
    {
        final JFrame frame = new JFrame("Text HIGHLIGHT");
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

        JPanel contentPane = new JPanel();
        contentPane.setBorder(BorderFactory.createTitledBorder(
                BorderFactory.createEmptyBorder(5, 5, 5, 5), "Highlighter JTextArea"));

        tarea = new JTextArea(10, 10);
        JScrollPane scrollPane = new JScrollPane(tarea);
        contentPane.add(scrollPane);

        JButton remHighButton = new JButton("REMOVE HIGHLIGHT");
        remHighButton.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent ae)
            {
                String input = JOptionPane.showInputDialog(frame, "Please Enter Start Index : "
                                                        , "Highlighting Options : "
                                                        , JOptionPane.PLAIN_MESSAGE);

                if (input != null && (highlights.size() > 0))
                {               
                    int startIndex = Integer.parseInt(input.trim());
                    Highlighter highlighter = tarea.getHighlighter();
                    highlighter.removeHighlight(highlights.get(startIndex));
                    tarea.setCaretPosition(startIndex);
                    tarea.requestFocusInWindow();
                    highlights.remove(startIndex);
                }
            }
        });

        JButton button = new JButton("HIGHLIGHT TEXT");
        button.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent ae)
            {
                String text = null;
                text = tarea.getSelectedText();
                if (text != null && text.length() > 0)
                {
                    int startIndex = tarea.getText().indexOf(text);
                    int endIndex = startIndex + text.length();
                    Highlighter highlighter = tarea.getHighlighter();

                    int selection = JOptionPane.showConfirmDialog(
                                            frame, getOptionPanel(), "Highlight Colour : "
                                                , JOptionPane.OK_CANCEL_OPTION
                                                , JOptionPane.PLAIN_MESSAGE);

                    System.out.println("TEXT : " + text);
                    System.out.println("START INDEX : " + startIndex);
                    System.out.println("END INDEX : " + endIndex);

                    if (selection == JOptionPane.OK_OPTION)
                    {
                        String colour = (String) cbox.getSelectedItem();
                        try
                        {
                            if (colour == colourNames[0])
                            {
                                System.out.println("Colour Selected : " + colour);
                                highlighter.addHighlight(startIndex, endIndex, redPainter);
                            }
                            else if (colour == colourNames[1])
                            {
                                System.out.println("Colour Selected : " + colour);
                                highlighter.addHighlight(startIndex, endIndex, orangePainter);
                            }
                            else if (colour == colourNames[2])
                            {
                                System.out.println("Colour Selected : " + colour);
                                highlighter.addHighlight(startIndex, endIndex, cyanPainter);
                            }
                            Highlighter.Highlight[] highlightIndex = highlighter.getHighlights();
                            System.out.println("Lengh of Highlights used : " + highlightIndex.length);
                            highlights.put(startIndex, highlightIndex[highlightIndex.length - 1]);
                        }
                        catch(BadLocationException ble)
                        {
                            ble.printStackTrace();
                        }
                    }
                    else if (selection == JOptionPane.CANCEL_OPTION)
                    {
                        System.out.println("CANCEL BUTTON PRESSED.");
                    }
                    else if (selection == JOptionPane.CLOSED_OPTION)
                    {
                        System.out.println("JOPTIONPANE CLOSED DELIBERATELY.");
                    }                   
                }
            }
        });

        frame.add(remHighButton, BorderLayout.PAGE_START);
        frame.add(contentPane, BorderLayout.CENTER);
        frame.add(button, BorderLayout.PAGE_END);

        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    private JPanel getOptionPanel()
    {
        JPanel panel = new JPanel();
        panel.setBorder(BorderFactory.createTitledBorder(
                        BorderFactory.createLineBorder(Color.DARK_GRAY, 2), "COLOUR SELECTION"));
        panel.setLayout(new GridLayout(0, 2, 5, 5));

        JLabel colourLabel = new JLabel("Select One Colour : ");
        cbox = new JComboBox(colourNames);

        panel.add(colourLabel);
        panel.add(cbox);

        return panel;
    }

    public static void main(String... args)
    {
        SwingUtilities.invokeLater(new Runnable()
        {
            public void run()
            {
                new TextHighlight().createAndDisplayGUI();
            }
        });
    }
}

输出：

开始 ：

重点第一线 第二

删除的要点

用不同的颜色突出显示同一行

与问题中的示例代码一致的最新编辑

import java.awt.*;
import java.net.MalformedURLException;

import javax.swing.*;
import javax.swing.text.*;

public class Test {
    public static void main(final String[] args) throws MalformedURLException {
        SwingUtilities.invokeLater(new Runnable() {

        @Override
        public void run() {
            try {
                init();
            } catch (BadLocationException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

        }
    });
}

private static void init() throws BadLocationException {
    JFrame frame = new JFrame();
    final JTextArea textArea = new JTextArea();
    JScrollPane pane = new JScrollPane(textArea);
    textArea.setText("Something. Something else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Samething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Sbmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Scmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Sdmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Semething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Sfmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nSomething. Sgmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n");
    textArea.setSelectionColor(Color.RED);
    frame.add(pane);
    frame.setSize(300, 120);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setVisible(true);

    String turnToString2 = "Sdmething else.\nA second line\na third line"
            + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla";
    int pos2 = textArea.getText().indexOf(turnToString2);
    Rectangle startIndex = textArea.modelToView(pos2);
    textArea.getHighlighter().addHighlight(pos2,
            pos2 + turnToString2.length(),
            new DefaultHighlighter.DefaultHighlightPainter(Color.yellow));    
    int y = startIndex.y + (pane.getHeight() - 10);
    System.out.println("Pane Height : " + pane.getHeight());
    System.out.println("X : " + startIndex.x);
    System.out.println("Y : " + y);
    System.out.println("Y (pos2) : " + startIndex.y);
    textArea.setCaretPosition(textArea.viewToModel(new Point(startIndex.x, y)));
    pane.scrollRectToVisible(new Rectangle(startIndex.x, y));
    }
}

这是输出：

Answer 2

要设置选择背景颜色，请使用setSelectionColor（如下所示，但未使用）。

我真的不明白您在说什么总是出现在窗口底部。 我想将其放在顶部，但我猜（这里我可能错了），您的文本区域在滚动窗格中，并且通过突出显示文本滚动到您选择的末尾，因此我建议设置插入标记的位置突出显示文本后。

这是我了解的示例。 让我知道这是否不是您想要的东西：

import java.awt.Color;
import java.net.MalformedURLException;

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.SwingUtilities;
import javax.swing.text.BadLocationException;
import javax.swing.text.DefaultHighlighter;

public class Test {
    public static void main(final String[] args) throws MalformedURLException {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                try {
                    init();
                } catch (BadLocationException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }

            }
        });
    }

    private static void init() throws BadLocationException {
        JFrame frame = new JFrame();
        final JTextArea textArea = new JTextArea();
        JScrollPane pane = new JScrollPane(textArea);
        textArea.setText("Something. Something else.\nA second line\na third line"
                + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n"
                + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla\nBlabla\n");
        textArea.setSelectionColor(Color.RED);
        frame.add(pane);
        frame.setSize(300, 120);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
        String turnToString = "Something else.\nA second line\na third line"
                + "Blabla\nBlabla\nBlabla\nBlabla\nBlabla";
        final int pos = textArea.getText().indexOf(turnToString);
        textArea.getHighlighter().addHighlight(pos,
                pos + turnToString.length(),
                new DefaultHighlighter.DefaultHighlightPainter(Color.yellow));
        textArea.scrollRectToVisible(new Rectangle(0, 0, pane.getViewport().getWidth(), pane.getViewport().getHeight()));
            SwingUtilities.invokeLater(new Runnable() {
                    @Override
                    public void run() {
                        textArea.setCaretPosition(pos);
                    }
            });
    }
}

Answer 3

我认为在使用荧光笔的情况下无法为所有JTextComponents更改这些方法，但是只能更改前景

例如

import java.awt.*;
import javax.swing.*;
import javax.swing.text.DefaultHighlighter;

public class TextAreaLineHightLight {

    public static void main(String[] args) throws Exception {
        UIManager.put("TextArea.selectionBackground", Color.yellow);
        UIManager.put("TextArea.selectionForeground", Color.red);

        String string = "Lorem ipsum eum putant gubergren evertitur in, "
                + "no assueverit vituperatoribus eum. Ea cibo offendit vim, est et vivendum qualisque prodesset. "
                + "Vis doctus expetenda contentiones an, no ius mazim epicuri expetendis, "
                + "saperet salutandi forensibus ne usu. Ex fugit alterum usu. "
                + "His ignota cotidieque in, augue erroribus eam no.";
        JTextArea textArea = new JTextArea(string);
        textArea.setLineWrap(true);
        textArea.setWrapStyleWord(true);
        JScrollPane textAreaScroll = new JScrollPane(textArea);
        JFrame frame = new JFrame();
        frame.setLayout(new BorderLayout());
        frame.add(textAreaScroll, BorderLayout.CENTER);
        frame.setSize(400, 300);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
        String term = "qualisque prodesset. "
                + "Vis doctus expetenda contentiones an, no ius mazim epicuri expetendis";
        int termOffset = string.indexOf(term);
        Rectangle view = textArea.modelToView(termOffset);
        int startOffset = textArea.viewToModel(new Point(0, view.y));
        //int rowH = textArea.
        int endOffset = textArea.viewToModel(new Point(textArea.getSize().width, view.y));
        textArea.getHighlighter().addHighlight(startOffset, endOffset, new DefaultHighlighter.DefaultHighlightPainter(Color.YELLOW));
    }
}

对于JTextPane具有相同的结果

import java.awt.*;
import javax.swing.*;
import javax.swing.text.*;

public class TextPaneHighlighting extends JFrame {

    private static final long serialVersionUID = 1L;
    private Highlighter.HighlightPainter cyanPainter;
    private Highlighter.HighlightPainter redPainter;

    public TextPaneHighlighting() {
        UIManager.put("TextPane.selectionBackground", Color.yellow);
        UIManager.put("TextPane.selectionForeground", Color.red);
        JTextPane textPane = new JTextPane();
        textPane.setText("one\ntwo\nthree\nfour\nfive\nsix\nseven\neight\n");
        JScrollPane scrollPane = new JScrollPane(textPane);
        getContentPane().add(scrollPane);//  Highlight some text
        cyanPainter = new DefaultHighlighter.DefaultHighlightPainter(Color.cyan);
        redPainter = new DefaultHighlighter.DefaultHighlightPainter(Color.red);
        try {
            textPane.getHighlighter().addHighlight(0, 3, DefaultHighlighter.DefaultPainter);
            textPane.getHighlighter().addHighlight(8, 14, cyanPainter);
            textPane.getHighlighter().addHighlight(19, 24, redPainter);
        } catch (BadLocationException ble) {
        }
    }

    public static void main(String[] args) {
        TextPaneHighlighting frame = new TextPaneHighlighting();
        frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
        frame.setSize(300, 200);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }
}

Answer 4

解决方案2）使用modelToView获取第一个选定行的点。 然后，使用Point使用scrollRectToVisible（注意：矩形的高度必须是您的视口高度）。