Problems with synchronization in JLabel (and Swing at all)

From: Chrosciu (chrosciu_at_poczta.onet.pl)
Date: 01/27/05 

Date: 27 Jan 2005 04:11:14 -0800

I have written a small program in Java, which performs complicated and
long-lasting calculations. So I want to illustrate the progress of
these calculations by a text (percent work done) placed in JLabel
component. But I have a "small" problem - this text doesn't change
during the calculations and after them it is set at once to 100%. The
source code is as follows :

percent = 0;

for (....)

{

// calculations

percent +=... //small progress value

Label2.setText(Double.toString(percent));

}

I have searched Web and read this can be caused by non-synchronized
threads of GUI and rest of program, but I don't know how it can be
repaired. I've already tried one method (shown below) but it also
doesn't work (effects are the same as in first program):

static void setTextOnLabel(final String text)
{
       
                       
               SwingUtilities.invokeLater(new Runnable()
               {
                   public void run()
                   {
                       jLabel2.setText(text);
                   }
           });
                       
               

}

....

percent = 0;

for (....)

{

// calculations
percent +=...

setTextOnLabel(Double.toString(percent));

}

Can anyone help me? Thanks in advance

Chrosciu

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