widget box problem in tk

prince26121991 has asked for the wisdom of the Perl Monks concerning the following question:

I am beginner in perl Tk Sometime ago I asked even a book for perl Tk but you people suggested me to go through online documentation rather than a book coz documentation are more up2date in compare of a book so here is what I made

use Tk;
use strict;
my $mw = MainWindow->new;
$mw->geometry("200x300");
$mw->title("MAIN WINDOW");
my $lname1;
my $button_frame1 = $mw->Frame()->pack(-side => "top");
$button_frame1->Button(-text => "GI EXTRACTOR", -command => \&window1)
+->pack();

sub window1
    {
my $mw = MainWindow->new;
    $mw->geometry("700x700");
    $mw->title("GI EXTRACTOR WINDOW");
    

    my $button_frame1 = $mw->Frame()->pack(-side => "top");
    $button_frame1->Button(-text => "Browse File", -command => \&updat
+e_output1)->pack(-side => "top");
    
    my $bf1 = $mw->Frame()->pack(-side => "top");
    $bf1->Label(-text => "You Have Selected The Following File")->pack
+(-side => "left");
    $bf1->Entry(-bg=>'red',-textvariable => \$lname1)->pack(-side => "
+left");
    
    my $b_f1 = $mw->Frame()->pack(-side => "top");
    
    $b_f1->Button(-text => "Ok", -command => \&u_o1)->pack(-side => "b
+ottom");
    
    my $output_frame1 = $mw->Frame()->pack(-side => "bottom");
    my $output_scroll1 = $output_frame1->Scrollbar();
    my $output_text1 = $output_frame1->Text(-yscrollcommand => ['set',
+ $output_scroll1]);
    $output_scroll1->configure(-command => ['yview', $output_text1]);
    $output_scroll1->pack(-side => "right", -expand => "no", -fill => 
+"y");
    $output_text1->pack();
    
    sub update_output1
        {
        my $button_frame1 = $mw->getOpenFile();
        $lname1=$button_frame1;
        }

sub u_o1 {
my $output1;
open(FH,"<$lname1");
while(my $_=<FH> )
{
if($_=~/^>gi/)
{
my@arr=split(/\|/,$_);
 $output1=$arr[0].$arr[1];
}

}
close(FH);

  $output_text1->delete('0.0', 'end');
  $output_text1->insert("end", $output1);
}
}
MainLoop;
[download]

This is a simple Tk program which opens a Main Window having a button called"GI Extractor" After clicking on it gives a new window" GI Extractor WINDOW" having total 5 widget

1.Browse file(which call getOpenFile()); 2.label (shows hardcoded text); 3.ENTRY(which show address of selected file); 4.ok button (which call mechanism of this program); 5.scrollbox(which shows ouput);

Now when I click on GI Extractorbutton in "Main Window", It works like a charm

But when once I close "GI EXTRACTOR WINDOW"and Reopen it using same button It neither Deletes previous entry nor takes new Entry

Instead of it gives a very long error in Command line

Hoping for a good reply with some example code coz I searching for this problem since last 5 hour please help

Comment on widget box problem in tk Download Code

Replies are listed 'Best First'.
Re: widget box problem in tk by Anonymous Monk on May 12, 2014 at 03:00 UTC
... Reopen it using same button It neither Deletes previous entry nor takes new Entry ... Yup, typical coping with scoping issue ( life cycle of variables ), see lots and lots links in Re^2: Perl Gtk2 - ->destroy() is Not Causing the Script to Exit links like Re^2: Border-less main window (Alt+F4 Ctrl+C , Re: Perk Tk - how to send a value from a subroutine back to the main program using Button (without MainLoop), Re: Perl tk FindNext in a text widget, Confused by variable scope in Tk::Wizard Then write Tk callbacks all lexically scoped and not-memory leaking with no nested subs ever :) avoid nested subs and closures because nested named subs because they're closures Also, meaningful variable/function names are good :) Here is your program slightly fixed up (so it doesn't error message), could use more fixing (for readability/understandability...) ... if you don't understand the changes I made start with a pencil & paper description of your program:) Read more... (4 kB) Hoping for a good reply with some example code coz I searching for this problem since last 5 hour please help I'd be very interested to learn what keywords you searched for	[reply] [d/l]
Re^2: widget box problem in tk by prince26121991 (Novice) on May 12, 2014 at 04:25 UTC
Thank you So Much Sir! Well I'll read All these link and will try to understand what change u exactly made! Ur program were not working perfectly I made a change in it :p `open my( $fh ), '<', $$lnameref; while( my $_ = <FH> )` [download] `open my( $fh ), '<', $$lnameref; while( my $_ = <$fh> )` [download] Now It's Perfect! It's been whole night spent on it thats why am sleepy now but if der will be some problem in any line thn I'll get back to u on it! u asked for terms! here are some of them! http://prntscr.com/3ig7pl Thank You So Much!	[reply] [d/l] [select]
Re: widget box problem in tk by ww (Archbishop) on May 12, 2014 at 12:18 UTC
Trying to understand the error would have helped you. `C:\>1085723.pl Variable "$mw" will not stay shared at 1085723.pl line 42. Variable "$output_text1" will not stay shared at 1085723.pl line 60.` [download] and trying to actually execute the file would have added critical information: `Use of uninitialized value $lname1 in concatenation (.) or string at 1 +085723.pl line 48. readline() on closed filehandle FH at 1085723.pl line 49.` [download] Careful study of the "very long error in Command line" will help you; quoting it will help us to help you. *Questions containing the words "doesn't work" (or their moral equivalent) will usually get a downvote from me unless accompanied by:* code verbatim error and/or warning messages *a coherent explanation of what "doesn't work* actually means.** check Ln42!	[reply] [d/l] [select]