Here you go. You need to use -browse2cmd to get the index number of the selected item.

use Tk;
use Tk::BrowseEntry;

my @items;
my $BrowseEntryindex;
my $cur_index;

my $mw = MainWindow->new();
$items[0]{'cmd'} = sub{print "First BrowseEntry Index Selected\n"};
$items[1]->{'cmd'} = sub{print "Second BrowseEntry Index Selected\n"};

my $dropdown = $mw->BrowseEntry( -label => 'Items',-browse2cmd => sub{
+&{$items[$_->{'_BE_curIndex'}]{'cmd'}};} )->pack;
$dropdown->insert('end', 'First');
$dropdown->insert('end', 'Second');

$mw->MainLoop;
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