Help with get_text() for Gtk3::Entry widget

[tsuyoshi okita <825864 gmail com>]

Hello, I am a Gtk3+ newbie.  I'm having a trouble with get_text() using 
Gtk3::Entry.
It works fine if I call Gtk3::Entry->new to an ordinary scalar variable 
like my $entry = Gtk3::Entry->new;But if I tried to add a Entry 
reference to an array or symbol referenced formatted name , I get the 
following error message:

*** unhandled exception in callback:
***   Can't call method "get_text" on an undefined value at 
lib/Tsuyoshi/Gtk3.pm line 242.
***  ignoring at /usr/share/perl5/Gtk3.pm line 137.

This is my code snippet:
                my $row_num = 5;
                my $max_row_num = 9;
                my $image_num = 1;

                no strict 'refs';
                for my $i ( $row_num...$max_row_num){
                    no strict 'refs';
                    ${"recipient_entry_".$i};
                    ${"recipient_image_".$i};
                }

                my $add_recipient_button = 
$builder->get_object('add_recipient_button');

                $add_recipient_button->signal_connect( clicked => sub {
                        if ($row_num > $max_row_num) { return; }
                        ${"recipient_entry_".$row_num} = Gtk3::Entry->new;
                        ${"recipient_image_".$row_num} = 
Gtk3::Image->new_from_stock('gtk-cancel',2);
                        print "var = ".${"recipient_entry_".$row_num}, 
"\n";
                        print "var = ".${"recipient_image_".$row_num}, 
"\n";
$page2_grid->attach(${"recipient_entry_".$row_num},1,$row_num,1,1);
$page2_grid->attach(${"recipient_image_".$row_num},2,$row_num,1,1);
${"recipient_entry_".$row_num}->signal_connect( changed => sub {
                                my $recipient_email = 
${"recipient_entry_".$row_num}->get_text;
                                if ( $recipient_email ne ""){
                                    my $email_obj = Email::Valid->new( 
-mxcheck => 1,
   -allow_ip=> 0);
                                    my $checked_address = 
$email_obj->address($recipient_email);
                                    if ($checked_address){
${"recipient_image_".$row_num}->set_from_stock('gtk-apply', 2);
                                        $first_page_check{'email'} = 1;
                                    }else{
${"recipient_image_".$row_num}->set_from_stock('gtk-cancel', 2);
$first_page_check{'recipient'} = 0;
                                    } # if2
                                }else{
${"recipient_image_".$row_num}->clear;
                                    $first_page_check{'recipient'} = 0;
                                }
                                if ( $first_page_check{'recipient'} == 
1 && $first_page_check{'port'} == 1 && $first_page_check{'email'} == 1  ) {
$assistant->set_page_complete($page2_grid, 1);
                                } # if
                            } # sub
                        ); # signal_connect
                        $page2_grid->show_all;
                        $row_num++;
                        $image_num++;
                    } # sub
                ); # signal_connect

                use strict 'refs';

Thank you for your help.

Yoshi