Question

my problem is that the subroutine from “-browsecmd” is called twice, when a user clicks on an entry. It activates when the left mouse button is pressed and when it is released. Is it possible to tell “-browsecmd” to only activate once?

Here is an example script that demonstrates my problem. Whenever a user clicks on an entry the print function is called twice.

#!/usr/bin/perl 

use strict;
use warnings;
use English qw( -no_match_vars );

use Tk;
use Tk::Tree;

my $mw   = MainWindow->new();
my $tree = $mw->Tree(
    -width     => '25',
    -browsecmd => \sub {
        my ($numbers) = @ARG;
        print $numbers. "\n";
    }
);

foreach (qw(one two three four five six )) {
    $tree->add( $ARG, -text => $ARG ); #populates the tree
}

$tree->pack();

MainLoop();

Thanks for reading my message.

EDIT1: Forgot to post the link to the Tk::Tree Documentation

Answer 1

There’s way to get rid of that behavior:

my $tree = $mw->Tree(
    -width     => '25',
    -selectmode => "single", # <= this makes it work
    -browsecmd => \sub {
        my ($numbers) = @ARG;
        print $numbers. "\n";
    }
);

Found this by browsing the doc for the parent widget: Tk::HList (the BINDINGS section is interesting).