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

This is my first post, so please be gentle if I have made any noob mistakes :)

I have found a post that attempts to tackle this problem, but the solutions provided are not very simple, or complete.

see Using Tk::Text and '<<Modified>>'

I need:

I am looking for something as simple as (or as close as possible): 

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

use Tk;

# Global variables
my $entry_val;

# Main Window
my $mw = new MainWindow;
$mw->Entry(
   -validate=>"all", 
   -validatecommand=>\&handleEvent, 
   -textvariable=>\$entry_val,
)->pack();

MainLoop;

# Callbacks
sub handleEvent {
   my ($new_val, $chars_2_change, $curr_val, $index, $action) = @_;

   # do nothing if No Change and No Force Validate
   if (!$chars_2_change && $action != -1){
      return;
   }

   # do something meaningful here.
   # for now, just print the $new_val
   print $new_val."\n";
}

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While the above code works great, it only satisfies 2 out of my 3 requirements. I am hoping that I have missed a widget that provides this functionality simply, or some option(s) of Entry that I may have overlooked to provide scrollable multi-line support.

  • Comment on using TK Text (or something similar), is there a simple way to get the -validate=>"all" functionality in TK Entry?
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Re: using TK Text (or something similar), is there a simple way to get the -validate=>"all" functionality in TK Entry?
by Khen1950fx (Canon) on Jun 20, 2011 at 01:30 UTC
    This is as far as I could go with it. I couldn't get it to scroll, but maybe this can get you started. 
    #!/usr/local/bin/perl

use strict;
use warnings;
use Tk;
use Tk::EntryCheck;

my $entry_val;

my $mw = MainWindow->new;
$mw->geometry("500x200");
$mw->title("Value Entry");

my $mf = $mw->Frame()->pack(-side => 'top', -fill => 'x');
my $tf = $mf->Frame(-background => "red")->pack(-side => 'top',
                                         -fill =>'x');
my $lf = $mf->Frame(-background => "black")->pack(-side => 'left',
                                         -fill => 'y');
my $rf = $mf->Frame(-background => "white")->pack(-side => "right");
$tf->Label(-text => "Value Entry",
           -background => "red")->pack(-side =>"top");
$lf->Label(-text => "Enter value:", -background => "black",
           -foreground => "yellow")->pack(-side => "left");

my $entry = $lf->EntryCheck( -validate => "all"
)->pack(-side => "left");

my $copy_button = $lf->Button(-text => "Copy Value",
           -command => \&copy_values)->pack(-side => "right");
my $clear_entries = $rf->Button(-text => "Clear Value",
           -command => \&clear_entries)->pack(-side => "top");
my $paste_entries = $rf->Text(-background => "black",
           -foreground => "green")->pack(-side => "top");

sub handleEvent {
   my ($new_val, $chars_2_change, $curr_val, $index, $action) = @_;
   if (!$chars_2_change && $action != -1) {
      return;
   }
   print $new_val."\n";
}

sub clear_entries {
    $paste_entries->delete('0.0', 'end');
}

sub copy_values {
    my $copied_text = $entry->get();
    $paste_entries->insert("end", $copied_text);
}

MainLoop;

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Re: using TK Text (or something similar), is there a simple way to get the -validate=>"all" functionality in TK Entry?
by zentara (Cardinal) on Jun 20, 2011 at 11:36 UTC
    I think you've seen all possible tricks for Tk, but I will also mention that Gtk2 has a text widget that might satisfy your requirements. 
    #!/usr/bin/perl -w
use strict;
use Gtk2 -init;

my $window = Gtk2::Window->new;
$window->signal_connect (destroy => sub {Gtk2->main_quit});
$window->set_default_size (400, 300);

my $textview = Gtk2::TextView->new;
$window->add ($textview);

my $n;
$textview->get_buffer->signal_connect (
         changed => sub { print "changed! ".(++$n)."\n"});

$window->show_all;
Gtk2->main;

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    I'm not really a human, but I play one on earth.
    Old Perl Programmer Haiku ................... flash japh
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Re: using TK Text (or something similar), is there a simple way to get the -validate=>"all" functionality in TK Entry?
by Anonymous Monk on Jun 20, 2011 at 09:18 UTC
    Hmm, validating only makes sense for single-line widgets ... anywho 
    #!/usr/bin/perl --
use Tk;
use strict;
use warnings;
Main(@ARGV);
exit(0);
sub Main {
    our $status = "";
    my $mw = tkinit;
    my $t = $mw->Scrolled(qw/
        Text
        -relief sunken
        -borderwidth 2
        -setgrid true
        -height 30
        -scrollbars e
    /)->pack(qw/
        -expand yes
        -fill both
    /);
    my $l = $mw->Label(
        -textvariable => \$status,
        -relief => 'groove',
        -font => "Arial",
        -anchor => 'center',
    )->pack(
        -side => 'bottom',
        -anchor => 's',
        -fill => 'both',
    );
    use DDS; Dump( $l );
    $t->bind( '<<Modified>>' => [ \&onModified , $t , $l ]);
    MainLoop;
}
sub onModified {
## warn " @_ "; ## go-figure , probably a bug
##  Tk::Text=HASH(0xeb324c) Tk::Frame=HASH(0xed2fcc) Tk::Label=HASH(0x
+fbfb94)
    my( $t,  undef, $l ) = @_; 
    if( $t->editModified ){
        $t->editModified(0); ## reset count
        if( "invalid" ){
            $t->bell;
            $::status = "invalid, forever";
            $l->configure ( -background => 'red' );
        }
    }
    return;
}

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