Hello

Here is a section of my perl program that uses the Tk module. I have two listboxes in the same window 
sub meter{
    
 my $metw = MainWindow-new;                                
 $metw->geometry("500x500");
 $metw->title("Meter work    details");                          
 $metw->configure(-background=>'purple');
       
 my $frame8=$metw->Frame(-relief=>'groove', -borderwidth=>3, -backgrou
+nd=>'blue',)->pack(-side=>'top', -pady=>15, -padx=>15);

my $label8=$frame8->Label(-text=>'Enter consumer name',-background=>'b
+lue', -foreground=>'white',)->pack(-side=>'left');

$entry8=$frame8->Entry(-width=>30,-background=>'white')->pack(-side=>'
+left', -pady=>3);
       
($label10 = $metw->Label(-text=>'Double click on subdivision name',-ba
+ckground=>'blue', -foreground=>'white'))->pack(-side=>'top',-pady=>2)
+;

$sd_list = $metw->Listbox(-exportselection => 0)->pack;

$sd_list->insert('end', "loc1","loc2","loc3","loc4","loc5","loc6", "lo
+c7", "loc8", "loc9","loc10","loc11","loc12","loc13");

 $sd_list->bind('<Double-1>', \&meter_subdivision);
            
           sub meter_subdivision {
            
                     my $sd = $sd_list->get('active');
                     
                  return $sd;                 
                   
          }

($space16 = $metw->Label(-text=>'             ',-background=>'purple')
+)->pack;
($space17 = $metw->Label(-text=>'             ',-background=>'purple')
+)->pack;    
       
($labeln = $metw->Label(-text=>'Double click on appropriate option',-b
+ackground=>'blue', -foreground=>'white'))->pack(-side=>'top',-pady=>2
+);

$nr_list = $metw->Listbox(-listvariable => $_, -exportselection => 0)-
+>pack;
                                  
$nr_list->insert('end',"New service","Replacement");
                               
$nr_list->bind('<Double-1>',\&type_meter_work);
            
                 sub type_meter_work {
            
                     my $tmw = $nrd_list->get('active');
                 
                     return $tmw;  
                 }                     
                 
                   
($space8 = $sw->Label(-text=>'             ',-background=>'purple'))->
+pack;
($space9 = $sw->Label(-text=>'             ',-background=>'purple'))->
+pack;
       
my $label7=$metw->Label(-text=>'Enter phase : single/three',-backgroun
+d=>'blue', -foreground=>'white',)->pack(-side=>'top');
$entry7=$metw->Entry(-width=>30,-background=>'white')->pack(-side=>'to
+p', -pady=>3);
       
$space10 = $sw->Label(-text=>'             ',-background=>'purple'))->
+pack;
$space11 = $sw->Label(-text=>'             ',-background=>'purple'))->
+pack;
                  
$metw->Button(-text=>'Print receipt',-background=>'blue',-command=>\&m
+eter_fwrite_print)->pack(-side=>'top',-pady=>2);
   
}

[download]
When i try to print the selected items in both the lists in another subroutine, i get the following error: 
Tk::Error: Can't call method "get" on an undefined value at C:\Perl\pr
+ograms\cash_counter.pl line 167.
 <Double-Button-1>
 (command bound to event)

[download]
If i have only one listbox in the window the value of the selected item is printed just fine.

In fact i would like to replace the"Enter phase" label with a list box too to reduce typing for the user.So three listboxes in one window.

Also how to use a single click instead of double click for selection.Will this cause any problems?

Please help.

In reply to Perl/Tk listbox question by perl_seeker

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