perl/tk changing button commands

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

i have a perl/tk program witch is just a text widget, and a button, and i want the text to change everytime i click the button. so i need to be able to change the command of the button each time it is clicked, does anybody know how to do this? here is the code:

#!/usr/bin/perl 

use strict;
use warnings;
use Tk;

sub one;

my $main = MainWindow->new;

my $label1 = $main->Text
(
    '-width'=>'50'
)->pack;

my $button = $main->Button
(
    -text=>'next',
    -command=>sub{one}
)->pack;

MainLoop;

sub one
{
    my $talk2="number1";
    my $talk="this text will be changing after every click of the butt
+on.";
    $label1 -> insert('1.0',"$talk");
    my $button = $main->Button(-text=>'next',-command=>sub{two})->pack
+;
}

sub two
{
# change the text box again
}
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Re: perl/tk changing button commands by Improv (Pilgrim) on Apr 22, 2003 at 17:30 UTC
Some comments I doubt you really mean to be adding all those new buttons everytime you click 'next', right? You might want to read up about how the Tk event loop works. You had the syntax for -command incorrect. You either pass it an anonymous subroutine (as in the $button2 example below) or a code reference, with \& See below for corrected code. Read more... (719 Bytes)	[reply] [d/l]
Re: perl/tk changing button commands by hiseldl (Priest) on Apr 22, 2003 at 21:38 UTC
If you want to change the action of the button every time it is pressed, then you need to leave out the `-command` switch and bind the 'ButtonPress' action later. This will allow you to re-bind the action once you have pressed the button. Here's an example: #!/usr/bin/perl use strict; use warnings; use Tk; my $main = MainWindow->new; my $text = $main->Scrolled('Text', -width=>'50' )->pack; my $button = $main->Button(-text=>'next', )->pack; $button->bind('<ButtonPress>', \&one); MainLoop; sub one { my $talk="One! Click for two.\n"; $text -> insert('1.0',"$talk"); $button->bind('<ButtonPress>', \&two); } sub two { my $talk="One! Click for three.\n"; $text -> insert('1.0',"$talk"); $button->bind('<ButtonPress>', \&three); } sub three { my $talk="One! Click for one.\n"; $text -> delete('1.0', 'end'); $text -> insert('1.0',"$talk"); $button->bind('<ButtonPress>', \&one); } [download] Cheers! -- hiseldl What time is it? It's Camel Time!	[reply] [d/l] [select]
Re: perl/tk changing button commands by kelan (Deacon) on Apr 23, 2003 at 13:56 UTC
How about just having an array that holds whatever pieces of text you want and looping through it. (Untested) `#!/usr/bin/perl use strict; use warnings; use Tk; my $main = MainWindow->new; my $label1 = $main->Text( -width => 50 )->pack; my $count = 0; my @texts = ( "This is the first piece.\n", "This is the second.\n", "This is the third.\n", "etc...\n", ); my $button = $main->Button( -text => "Next", -command => sub { $label1->insert('1.0', $texts[$count++]); } )->pack; MainLoop;` [download] kelan Perl6 Grammar Student	[reply] [d/l]