Some Tk Commands

bind
The bind command associates Perl code with events. If you want to do something when the user double-clicks a item in a listbox or when he/she press any button(say F1), bind is what you need. Lets bind something in the next example.

Syntax:
$widget -> bind(<sequence>, Callback);
<sequence> stands for the sequence of button/mouse presses. It should be given in the following pattern...
<modifier-modifier-type-detail> . For example...
<Control-Alt-Key-t> - Control+Alt+T.
Control and Alt are the modifiers and Key is the type with t as the detail. See the next example and you will understand.

#!/usr/local/bin/perl
use Tk;
# Main Window
my $mw = new MainWindow;

my $lab = $mw -> Label(-text=> " The Bind command ",
	-font=>"ansi 12 bold") -> pack;
my $lst = $mw -> Listbox() -> pack;
$lst -> insert('end',"Don't double-click this.");
$lst -> insert('end',"Don't double-click this either.");
$lst -> insert('end',"Don't even think of double-clicking this.");
$lst -> insert('end',"You may double-click this.");
$lst -> insert('end',"No. Negative. Nay. Nope. Get the message?");
#Bind the double click event to the list box
$lst -> bind ('<Double-ButtonPress-1>', sub { double() });

my $all_keys = $mw -> Label(-justify=>"left",
	-text=>"Press any of the following...
Control+A
Control+Shift+A
Control+Alt+T
Right click
Control+Escape") -> pack;

#Exit when the escape key is pressed
$mw -> bind('<Key-Escape>', sub { exit });
#Shows a helping dialog box when F1 is pressed
$mw -> bind('<Key-F1>',sub { help(); });
#Binds misc keys.
$mw -> bind('<Control-Key-a>', sub { 
	$mw -> messageBox(-message=>"You pressed Control+A, did'nt you?")
});#Control+A
$mw -> bind('<Control-Key-A>', sub { 
	$mw -> messageBox(-message => "Control+Shift+A, right?"); 
	});#Control+Shift+A
$mw -> bind('<Control-Alt-Key-t>', sub { 
	$mw -> messageBox(-message => "Control, Alt and T"); 
});#Control+Alt+T
$mw -> bind('<ButtonPress-3>', sub { 
	$mw -> messageBox(-message => "The right way to click."); 
});#Right click
$mw -> bind('<Control-Key-Escape>', sub { 
	$mw -> messageBox(-message => "You must be a married man. 
What you pressed remindes married men of what they never will have
 - Control or Escape.");
});#Control+Escape 

MainLoop;

#The helping function
sub help {
	$mw -> messageBox(-message=>"Did you ask of help?
You ain't getting any.
Ha Ha Ha!");
}

#This happens at double-click
sub double {
	$mw -> messageBox(-message=>"You double clicked something.
This script is simple - so it won't display what you clicked on.
But if you want a sript that is able to do that, 
write to me at binnyva\(at\)hotmail\(dot\)com
and I will send you a better script.");
}