in reply to perl Tk

Hi,

it is possible to do something similar using the -validate option:

  
$parent->Entry( -validate=>'key',
                -validatecommand=>['entry_validation',$self],
           );
#### snip
sub entry_validation{
  my $self = shift();
  my @args = @_;
  $self->set_changed unless ($args[4]== -1);#triggered on user interac
+tion only
  return 1; #allow changes
}

[download]

This will trigger on paste events as well. - I'm not checking for changed content here. I think it would be possible - take a look at the documentation for -validatecommand


Cheers, Christoph

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Re^2: perl Tk
by jagdish.eashwar (Novice) on Sep 03, 2009 at 07:55 UTC

    I found something on the net at http://forums.devshed.com/perl-programming-6/perl-tk-how-to-call-the-event-s-object-entry-630717.html, and also got some confirmation from pg 273 of the book Learning Perl/Tk. Instead of specifying the individual entry boxes, one should use the Tk::Entry class. 

    use strict;
use warnings;

use Tk;

my ($mw,$EntryBox1,$EntryBox2,$variable1,$variable2,$entry,$variable_p
+revious,$variable_current);

$mw = MainWindow->new;
$EntryBox1 = $mw->Entry(-textvariable => \$variable1,
        )
        ->place(-relx => 0.06, -rely => 0.03);

$EntryBox2 = $mw->Entry(-textvariable => \$variable2,
        )
        ->place(-relx => 0.06, -rely => 0.20);

$mw->bind("Tk::Entry","<FocusIn>",\&save_previous_value);
$mw->bind("Tk::Entry","<FocusOut>",\&compare_values);

MainLoop;

sub save_previous_value {
$entry = shift;
print "$entry\n";
# i was hoping this would print '$EntryBox1' or '$EntryBox2'
# instead it gives me 'Tk::Entry=HASH(0x1bf2f7c)'
# or 'Tk::Entry=HASH(0x1bfa9a4)'
$variable_previous = $entry->get();
      }

sub compare_values {
$entry = shift;
$variable_current = $entry->get();
if ($variable_current ne $variable_previous) {
$mw->messageBox(-message => "The value has been changed.",-type => "ok
+");
       }
       }

    [download]

    Now the common sub works for all the entry widgets in the main window. I would however like to know the name of the concerned entry widget. Is there some way of finding that out?

[reply]
[d/l]
      Hi,

      what would you need that name for? If you want per instance behavior, you need to set up bindings per instance (I would prefer that) or stuff additional data into your widgets instance

      my %entries;
$entries{MyEntriesName} = $parent->Entry();
$entries{MyEntriesName}->privateData('MyPrivateDataSlot')->{Name}='MyE
+ntriesName';

      [download]

      Cheers, Christoph
[reply]
[d/l]

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