#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $value;

my $mw = MainWindow->new;

my $entry = $mw->Entry(
    -state        => 'readonly',
    -textvariable => \$value
)->pack;

my $lb = $mw->Listbox( -height => 0 )->pack;
$lb->insert( 'end', qw/one two three four five six/ );

$lb->bind( '<ButtonPress-3>', [ \&setItem, \$value, Ev('@') ] );

sub setItem {
    my ( $lb, $valSR, $xy ) = @_;

    $lb->selectionClear( 0, 'end' );
    my $index = $lb->index($xy);
    if ( defined($index) ) {
        $lb->selectionSet($index);
        $$valSR = $lb->get($index);
    }
}

MainLoop;
[download]

hello, i want to know how do i select a line in a listbox by the right click of the mouse. ...

What system? (Tk? Wx? ...)

(For list boxes in HTML forms, you'll need something that runs in the browser such as JavaScript. Perl won't be of use except on the few machines that have PerlScript installed.)

Update: The root post was changed. The original question made no mention of Tk. I've added a quote from the original version.

this is how listbox does it

sub ClassInit
{
 my ($class,$mw) = @_;
 $class->SUPER::ClassInit($mw);
 # Standard Motif bindings:
 $mw->bind($class,'<1>',[sub {
               my $w = shift;
               if (Tk::Exists($w)) {
                 $w->BeginSelect(@_);
               }
             }, Ev('index',Ev('@'))]);
 $mw->bind($class, '<Double-1>' => \&Tk::NoOp);
 $mw->bind($class,'<B1-Motion>',['Motion',Ev('index',Ev('@'))]);
 $mw->bind($class,'<ButtonRelease-1>','ButtonRelease_1');
 ;
 $mw->bind($class,'<Shift-1>',['BeginExtend',Ev('index',Ev('@'))]);
 $mw->bind($class,'<Control-1>',['BeginToggle',Ev('index',Ev('@'))]);

 $mw->bind($class,'<B1-Leave>',['AutoScan',Ev('x'),Ev('y')]);
 $mw->bind($class,'<B1-Enter>','CancelRepeat');
 $mw->bind($class,'<Up>',['UpDown',-1]);
 $mw->bind($class,'<Shift-Up>',['ExtendUpDown',-1]);
 $mw->bind($class,'<Down>',['UpDown',1]);
 $mw->bind($class,'<Shift-Down>',['ExtendUpDown',1]);

 $mw->XscrollBind($class);
 $mw->bind($class,'<Prior>', sub {
           my $w = shift;
           $w->yview('scroll',-1,'pages');
           $w->activate('@0,0');
       });
 $mw->bind($class,'<Next>',  sub {
           my $w = shift;
           $w->yview('scroll',1,'pages');
           $w->activate('@0,0');
       });
 $mw->bind($class,'<Control-Prior>', ['xview', 'scroll', -1, 'pages'])
+;
 $mw->bind($class,'<Control-Next>',  ['xview', 'scroll',  1, 'pages'])
+;
 # <Home> and <End> defined in XscrollBind
 $mw->bind($class,'<Control-Home>','Cntrl_Home');
 ;
 $mw->bind($class,'<Shift-Control-Home>',['DataExtend',0]);
 $mw->bind($class,'<Control-End>','Cntrl_End');
 ;
 $mw->bind($class,'<Shift-Control-End>',['DataExtend','end']);
 # XXX What about <<Copy>>? Already handled in Tk::Clipboard?
 # $class->clipboardOperations($mw,'Copy');
 $mw->bind($class,'<space>',['BeginSelect',Ev('index','active')]);
 $mw->bind($class,'<Select>',['BeginSelect',Ev('index','active')]);
 $mw->bind($class,'<Control-Shift-space>',['BeginExtend',Ev('index','a
+ctive')]);
 $mw->bind($class,'<Shift-Select>',['BeginExtend',Ev('index','active')
+]);
 $mw->bind($class,'<Escape>','Cancel');
 $mw->bind($class,'<Control-slash>','SelectAll');
 $mw->bind($class,'<Control-backslash>','Cntrl_backslash');
 ;
 # Additional Tk bindings that aren't part of the Motif look and feel:
 $mw->bind($class,'<2>',['scan','mark',Ev('x'),Ev('y')]);
 $mw->bind($class,'<B2-Motion>',['scan','dragto',Ev('x'),Ev('y')]);

 $mw->MouseWheelBind($class); # XXX Both needed?
 $mw->YMouseWheelBind($class);
 return $class;
}
[download]

Ah, question looks reasonably put now.

-David.