Try attaching scalar or scalaref instead of hashref to ballonmsg: 
use strict;
use warnings;
use Tk;
use Tk::Tree;
use Tk::Balloon;

my $mw = MainWindow->new();
my $h = $mw->Scrolled('Tree', -scrollbars=>'ose', -selectmode=>'extend
+ed')->pack(-side=>'top', -fill=>'both', -expand=>1);
my %help;
for my $top (1..3) {
    $h->add($top, -text=>$top);
    for (1..3) {
        $h->add("$top.$_", -text=>"$top.$_");
        $help{"top.$_"} = "help_$top.$_";
    }
}

my $b = $mw->Balloon(-initwait=>0);
#$b->attach($h->Subwidget('scrolled'), -balloonposition=>'mouse', -bal
+loonmsg=>\%help);
$b->attach($h->Subwidget('scrolled'), -balloonposition=>'mouse', -ball
+oonmsg=>"OK");

MainLoop();

[download]

In reply to Re: Using Tk::Balloon with Tk::Tree by ldln
in thread Using Tk::Balloon with Tk::Tree by gri6507

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