In your DragStart function, the following line: 
my $idx = $w->GetNearst($e->x, $e->y);

[download]
Should read: 
my $idx = $w->GetNearest($e->x, $e->y);

[download]

Your Drop function needs some changes as well. Instead of grabbing the x and y values through the properties of the directory tree, you should use the values that the Drop event sends through: 

sub Drop{
    my ($lb, $dnd_source, $c_dest, $sel, $dest_x, $dest_y) = @_;
    my $group_item = $dnd_source->cget('-text');
    my $nearest = $lb->GetNearest($dest_x, $dest_y);
    if (defined $nearest){
        my $dir_item = $lb->entrycget($nearest, '-text');
        print "*** $dir_item ***\n";    ### DEBUG: Show target value
        &AddGroupToDir($group_item, $dir_item);
        $lb->see($nearest);
    }
}

[download]
O'Reilly has a good Drag-and-Drop Primer available; you should check it out.

-- grummerX

Update: Removed HTML tags in code. (stupid, stupid...)

In reply to Re: A Drag and Drop (perl/Tk) question. by grummerX
in thread A Drag and Drop (perl/Tk) question. by blackadder

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