JTextArea focus

[GuzaPasha]

I am not able to get focus to the last line displayed in JTextArea, when I append to much lines in it. Just few of the first lines appeared. I can see the last lines by using scroll.

I'm using:

chatText = new JTextArea(10, 30);
chatText.setLineWrap(true);
chatText.setEditable(false);
chatText.setForeground(Color.white);
chatText.setBackground(new Color(80,0,0));
chatText.isManagingFocus();

What do I miss? and how to solve it.

Thanks
GuzaPasha

 

[prosper]

//use JScrollPane for JTextArea
// the following is part of code, copy the part you need
import java.awt.*; 
import java.awt.event.*;
import javax.swing.*; 
import javax.swing.event.*; 
import javax.swing.text.*; 

final int JT_COL = 50;
final int JT_ROW = 40;
JTextArea JT;
    JT = new JTextArea("oneone\ntwoone\nthree",JT_ROW,JT_COL);   
            JScrollPane scroller = new JScrollPane(); 
            scroller.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
            scroller.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
            JViewport vp = scroller.getViewport(); 
            vp.add(JT); 
    add(scroller);

 

[GuzaPasha]

still nothing, here is my code + your code

JPanel P = new JPanel(new BorderLayout());
      chatText = new JTextArea(10, 30);
      chatText.setLineWrap(true);
      chatText.setEditable(false);
      chatText.setForeground(Color.white);
      chatText.setBackground(new Color(80,0,0));
      chatText.isManagingFocus();

      /*JScrollPane chatTextPane = new JScrollPane(chatText,
         JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
         JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);*/
//your code from here
      JScrollPane chatTextPane = new JScrollPane();
      chatTextPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
      chatTextPane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
      JViewport vp = chatTextPane.getViewport(); 
      vp.add(chatText); 
//..      
P.add(chatTextPane, BorderLayout.CENTER);
//..

Please look at this.

GuzaPasha

 

[prosper]

import java.awt.*;
import javax.swing.*;
class jt extends JFrame
      {
       public jt()
              {
               super("jt");
               JPanel p = new JPanel(new BorderLayout());
               JTextArea chatText = new JTextArea("one\ntwo\nthree",10, 30);
               chatText.setLineWrap(true);
               chatText.setEditable(true);
               chatText.setForeground(Color.white);
               chatText.setBackground(new Color(80,0,0));

               JScrollPane chatTextPane = new JScrollPane();
               chatTextPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
               chatTextPane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
               JViewport vp = chatTextPane.getViewport(); 
               vp.add(chatText); 
               p.add(chatTextPane, BorderLayout.CENTER);
               getContentPane().add(p,BorderLayout.CENTER);
              }
       public boolean isManagingFocus() // all your JComponents should have this method overidden like this if you want to manage focus yourself
              {
               return true;
              }
       public static void main(String args[])
              {
               jt jtObj = new jt();
               jtObj.setSize(400,400);
               jtObj.setVisible(true);
              }
      }

 

[GuzaPasha]

Could you please put this into your code
for (i=1;i<50;i++){
chatText.append("line: " + i + "\n");
}

as you can see there is no focus. Maybe the focus is the wrong terminology, but here is exactly what I need.
Let's suppose that the JtextAre has 10 lines in height.
for (i=1;i<50;i++){
chatText.append("line: " + i + "\n");
}
will put the 50 lines of text in it. Scroll will not follow last line received, and will stay showing the first 10 lines. If I want to see the last line, i will have to scroll down manualy. I don't want this. I want the scroll is following the last line received. Is there a way that I can receive text in JTextArea always in the first line, and to scroll down previosuly received text.

Any idea?
guzapasha

 

[prosper]

// If you want to show the last 10 lines
// you should process the text in the JTextArea, store them into an string array with size of 10
// set JTextArea blank
// add 10 lines to JTextArea