use Tk;
$MW=MainWindow->new(-title=>'MyWindow');
$MW->Button(
-text=>'change',
-command=>\&change)->pack;
$LB=$MW->Label(-text=>'...')->pack;
MainLoop;
sub change
{
$LB->configure(-text=>'case 1');
sleep 3;
$LB->configure(-text=>'case 2');
}

[download]

When I clicked the button 'change',the button didn't rebound
until the call back function ended and I had never seen
'case 1' was printed but 'case 2'.
These two things are not my intentions.
I need your help,Thanks!

In reply to A question about Tk. by iic

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