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Solved

Aligning Textarea

Posted on 1997-08-21
4
463 Views
Last Modified: 2012-05-04
Question...

OK, this is probably really simple for a seasoned Java coder, but, I have
an application that opens a textarea as a log window. However, whenever
the window fills, the window does not automatically scroll down. Is there
a way to this?

Thanks...
0
Comment
Question by:slyfoxx
  • 2
4 Comments
 
LVL 10

Expert Comment

by:kollegov
ID: 1225514
try following example :
simply click on applet field to add row ro TextArea
This one scrolls in appletviewer in JDK1.02
I think you do not appended text but replaced all text setting
it with setText() method. That's why it doesn't scroll


import java.awt.*;
import java.net.*;
import java.applet.*;

        public class check extends Applet
        {int i=0;
         TextArea ta;
         public void init()
         {ta=new TextArea(10,10);
          add(ta);
          validate();
         }
         
         public boolean mouseDown(Event e, int x, int y)
         { ta.appendText("\n"+i);
           i++;
           return true;
         }
         

        }
0
 

Author Comment

by:slyfoxx
ID: 1225515
Sorry, No good.

Irrespective of whether I append to the textarea or recreate all the text, the view of the text in the textarea is the same, the view does not scroll down automatically. (i.e. Functionally the same as the scroll bar being at the top and not moving.)

I am running jdk 1.1.3 on a solaris 2.5 machine under X.

Here is a copy of the code I am using.

import java.awt.*;

public class monitor {
  Frame fr = new Frame("Simulator Monitor");
  TextArea txt = new TextArea("", 12, 72);
  String text = "";

  monitor() {
    fr.setSize(400,400);
    fr.setFont(new Font("Courier", Font.BOLD, 10));
    txt.setEditable(false);
    fr.add(txt);
    txt.append("----------------------------------\n");
    txt.append("Socket Connection Established\n");
    txt.append("----------------------------------\n\n");
    fr.show();
    fr.setLocation(300,300);
    }

 public void title(String t) {
    fr.setTitle("MR Simulator Monitor: "+t);
    }

  public void add(String t) {
    text = text+t;
    update();
    }

  public void add(int c, String t) {
    text = text+("("+c+") "+t);
    update();
    }

  public void addln(String t) {
    text = text+t+"\n";
    update();
    }

  public void addln(int c, String t) {
    text = text+"("+c+") "+t+"\n";
    update();
    }

  public void addln() {
    text = text+"\n";
    update();
    }

  public void update() {
    int end = text.length();
    txt.replaceRange(text, 0, end);
    }

}
0
 
LVL 1

Accepted Solution

by:
gerry99 earned 50 total points
ID: 1225516
I'd recommend using a List instead of a TextArea.

When you add an item call  

list.select( list.size()-1 );

to select the last item in this list.  This will scroll the list
so that the last line is selected.  The downside, is that
List doesn't come with a horizontal scrollbar, so each item
should fit within the width of your control.

Hope this helps.
0
 

Author Comment

by:slyfoxx
ID: 1225517
Interesting, I hadn't thought of it that way... Thanks...
0

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