Usually you use a Dialog for this, a toplevel is used only when the Dialog gives you problems. Try this: 
#!/usr/bin/perl
use strict;
use Tk;
use Tk::DialogBox;

my $dialog;
my $running = 0;
my $mw = new MainWindow(-title=>'My Main App');
my $text = $mw->Text();

my $loginbut = $mw->Button(-text=>'Login',
               -command => \&login)->pack;

my $logoffbut = $mw->Button(-text=>'LogOff',
               -command => sub {$running = 0} )->pack;

#&login;

MainLoop;

###############################################################
sub login{

return if $running;

$dialog = $mw->DialogBox(
    -title   => "Login",
    -buttons => [ "OK", "Cancel" ]
);

my $server = 'default';
my $servl = $dialog->add(
    "Label",
   -text => 'Server'
)->pack();
my $servd = $dialog->add(
    "Entry",
   -textvariable => \$server
)->pack();

my $name = 'default user';
my $namel = $dialog->add(
    "Label",
    -text => ' Name '
)->pack();
my $named = $dialog->add(
    "Entry",
    -textvariable => \$name
)->pack();

my $passwd;
my $passl = $dialog->add(
    "Label",
    -text => 'Password' 
    )->pack();

my $passd = $dialog->add(
    "Entry",
    -show         => "*",
    -textvariable => \$passwd
)->pack();

my $retlog = 0;
if ( $dialog->Show() eq "OK" ) {
    print "$server\t$name\t$passwd\n";    #this line is only for demo
    #do your stuff here, like reprompt if the 
    #password is bad, or whatever you want

    # here you would make a callback to a real login sub,
    # and if it is good, then enable the main gui
#     $retlog = &real_login($server,$name,$passwd);
  }
#if($retlog == 1){ &start_main } else { &login}
}

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In reply to Re: perltk-problem related to toplevel widget by zentara
in thread perltk-problem related to toplevel widget by perlplayer

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