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Message:

Scrolling

Posted by Jay on November 19, 2001 at 8:03 AM

Terry,

The immediate solution that I could think of is the one posted below. But frankly, I dont like it (the highlighted portion). Theres got to be a better way than this. I worked quite a bit trying to better it but just cant seem to think out of the box. Can you or anyone else help me here improve this? Also, how do you fire actions (the nested Action classes) in EditorKit?

import javax.swing.*;
import javax.swing.text.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.event.*;
import java.net.URL;
import java.io.*;
public class JavaEditor extends JFrame
{
	JEditorPane editorPane;
	JLabel status;

	public JavaEditor(String fileName)
	{
		super( "JavaEditor" );
       	JPanel contentPane = new JPanel();
        editorPane = createEditorPane(fileName);
        status = new JLabel( "You are at: 1, 1" );
        JScrollPane editorScrollPane = new JScrollPane(editorPane);
        editorScrollPane.setVerticalScrollBarPolicy( JScrollPane.VERTICAL_SCROLLBAR_ALWAYS );
        editorScrollPane.setPreferredSize( new Dimension(250, 145) );
        editorScrollPane.setMinimumSize( new Dimension(10, 10) );
		contentPane.setLayout( new BorderLayout() );
        contentPane.add( editorScrollPane, BorderLayout.CENTER );
        contentPane.add( status, BorderLayout.SOUTH );
        setContentPane( contentPane );
        addWindowListener(new WindowAdapter()
        {
            public void windowClosing(WindowEvent e)
            {
                System.exit(0);
            }
        });
		setSize(200, 200);
		setVisible(true);
	}
    private JEditorPane createEditorPane(String fileName)
    {
        final JEditorPane editorPane = new JEditorPane();
        editorPane.setEditorKitForContentType( "text/plain", new DefaultEditorKit() );
        editorPane.setEditable(true);
        try
        {
			editorPane.read(new FileInputStream(fileName), "Text File");
        }
        catch (Exception e)
        {
            System.err.println(e);
        }
        editorPane.addCaretListener(new CaretListener()
        {
            public void caretUpdate(CaretEvent e)
            {
				int lineNumber = 1;
				int columnNumber = 0;
				int currentPosition = editorPane.getCaretPosition();
				try
				{
					String strText = editorPane.getDocument().getText(0, currentPosition);
					char arrText[] = strText.toCharArray();
					for(int i=0; i					{
						if(arrText[i] == '\n') lineNumber++;
					}
					columnNumber = currentPosition - strText.lastIndexOf('\n');
				}
				catch(BadLocationException ble)
				{
					System.err.println(ble);
				}
				status.setText( "You are at: " + lineNumber + ", " + columnNumber );
            }
        });
        return editorPane;
    }
    public static void main(String[] args)
    {
		if(args.length != 1)
		{
			System.out.println("Usage: java JavaEditor fileName");
			System.exit(1);
		}
        new JavaEditor(args[0]);
    }
}

-Jay