在 java swing jtext 组件中突出显示更改文本

Question

我试图在 JEditorPane 中突出显示一些代码，如下所示：

import javax.swing.JEditorPane;
import javax.swing.JFrame;
import javax.swing.text.DefaultHighlighter;
import javax.swing.text.Highlighter;

public class Driver
{
    public static void main(String[] args)
    {
        try
        {
            //create a simple frame with an editor pane
            JFrame frame = new JFrame("Highlight Test");
            JEditorPane pane = new JEditorPane();
            frame.getContentPane().add(pane);
            frame.setSize(300, 300);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setVisible(true);

            //string to put in the pane
            String text = "1234567890";

            //grab the highlighter for the pane
            Highlighter highlighter = pane.getHighlighter();

            //store all the text at once
            pane.setText(text);

            //go through all the characters
            for(int i = 0; i < text.length(); i++)
            {
                //highlight the latest character
                highlighter.addHighlight(i, i + 1, DefaultHighlighter.DefaultPainter);

                //sleep for a quarter second
                Thread.sleep(250);
            }
        }catch(Exception ex){}
    }

}

这将一次突出显示一个字符，并且所有字符将保持突出显示。现在，我想要相同的行为（所有字符保持突出显示），但我想更改突出显示之间的文本，如下所示：

import javax.swing.JEditorPane;
import javax.swing.JFrame;
import javax.swing.text.DefaultHighlighter;
import javax.swing.text.Highlighter;

public class Driver
{
    public static void main(String[] args)
    {
        try
        {
            //create a simple frame with an editor pane
            JFrame frame = new JFrame("Highlight Test");
            JEditorPane pane = new JEditorPane();
            frame.getContentPane().add(pane);
            frame.setSize(300, 300);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setVisible(true);

            //string to put in the pane
            String text = "1234567890";

            //grab the highlighter for the pane
            Highlighter highlighter = pane.getHighlighter();

            //go through all the characters
            for(int i = 0; i < text.length(); i++)
            {
                //place a new string in the pane
                pane.setText(pane.getText() + text.charAt(i));

                //highlight the latest character
                highlighter.addHighlight(i, i + 1, DefaultHighlighter.DefaultPainter);

                //sleep for a quarter second
                Thread.sleep(250);
            }
        }catch(Exception ex){}
    }

}

注意窗格中的文本正在更改，然后我应用新的突出显示。旧的亮点消失了——我希望它们留下来。我的假设是每次 setText() 时突出显示都会消失。那么，有没有办法在改变文本的同时，保持文本组件中的高亮显示呢？

Answer 1

我没有尝试以下代码，但我建议只是尝试突出显示最新字符和以前的字符，如下所示：

        //go through all the characters
        for(int i = 0; i < text.length(); i++)
        {
            //place a new string in the pane
            pane.setText(pane.getText() + text.charAt(i));
          //highlight the previous characters
          if (i > 0) {
           for ( int j=i-1; j >= 0; j--)
             highlighter.addHighlight(j, j+1 , DefaultHighlighter.DefaultPainter);
           }
            //highlight the latest character
            highlighter.addHighlight(i, i + 1, DefaultHighlighter.DefaultPainter);

            //sleep for a quarter second
           // Thread.sleep(250);
        }
    }catch(Exception ex){}