Editplus functionality in List with TextArea

Question

Hi All,
I have merged the JList and JTextArea in the JSplitpane , and here
my problem is when enter the Text in a line of TextArea the respective line no should be increased one by one.That is exactly similar to the ' Editplus ' for delete the Textline and add the Textline.Is
any body have Idea pls direct me with samples.
Thanks in Advance.

Answer 1

You like to keep track of the lines in the TextArea? Add some listener - I added it as DocumentListener because I like it - you may also use a KeyListener or something and do the same. Then just ask the TextArea about the no of lines.
import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
public class IncreaseLineNo extends JFrame
    // the text area
    JTextArea theArea = new JTextArea();
    // a textfield showing the current no of lines in the textarea
    JTextField theField = new JTextField();
    public IncreaseLineNo(){
        super("Just a test");
        add(theArea, BorderLayout.CENTER);
        add(theField, BorderLayout.NORTH);
        theField.setEditable(false);
        theArea.getDocument().addDocumentListener(new DocumentListener(){
            public void changedUpdate(DocumentEvent e)
                theField.setText(String.valueOf(theArea.getLineCount()));
            public void insertUpdate(DocumentEvent e)
                theField.setText(String.valueOf(theArea.getLineCount()));
            public void removeUpdate(DocumentEvent e)
                theField.setText(String.valueOf(theArea.getLineCount()));
        setSize(42,42);
    public static void main(String args[]){
        new IncreaseLineNo().setVisible(true);
}