java - Label refresh function does not work -

i'm trying setup function takes input user , prints onto label , updates per entry. updating occur through removing old label , adding label updated value. text center-aligned. while i'm able label print current value of "entry", without removing label old value. wondering how able correct issue?

import acm.graphics.*; import acm.program.*;  public class testcanvas extends consoleprogram {      public void run()     {         gcanvas canvas = new gcanvas();         add(canvas);         string entry ="";         while(true)         {              entry += readline("give me word: ");             if(entry=="") break;             glabel label = new glabel(entry);             label.setlocation(200-label.getwidth()/2,                      60+label.getheight());              label.setfont("times new roman-24");             // remove old label , update              // label current value "entry"             canvas.remove(label);             canvas.add(label);          }     } } 

your infinite loop prevents label updating. need ui thread, update asynchronously.