I'm trying to retool to Perl from Ansi C (dabbled only slightly in C++ years ago.) I am writing an app that uses a database. I pull the needed data from the database at the beginning of Package MyFrame, and then attempt to handle an EVT_COMBOBOX, but can't seem to pass data to the event handler. I basically need to get the selected combo box entry to the event handler sub so that I can use it in the sub. How is this done? (I'm familiar with passing pointers in C. I think that "aliasing" may be analogous to that, but I don't know how it's done in Perl.) I've made a few vain attempts, but can't seem to find examples for Perl WxWidgets that apply. So far my code is simply in a proof-of-concept state (cut and paste from examples with a few adjustments of my own). So sub Combobox1action is generic and has nothing in it but place holding code. It does execute in its present state, but I'm at a stalemate with it. Below is the MyFrame package.

package MyFrame;
    
use base 'Wx::Frame';
use Wx::Event qw(EVT_BUTTON
                 EVT_COMBOBOX
);

my $sth;
my $tablename;
my $sqlcommand;
my @lessonnumber;
my @lessonsimplename;
my @lessontitle;
my @startingpagenumber;
my $nameargument;
my $increment = 0;

my $dbh = DBI->connect("dbi:mysql:*********", "root","*******")
    or die "Can't connect to MySQL database: $DBI::errstr\n";

$sqlcommand = "SELECT lessonstring, lesson_number, description, starti
+ng_pagenumber FROM lesson_titles";

$sth = $dbh->prepare ($sqlcommand)
    or die "Cannot perform SQL INSERT: $DBI::errstr\n";

$sth->execute( )
    or die "Cannot perform execute\n";

for ( $increment = 1; $increment <= 132; $increment++ ) {
     ( $lessonsimplename [ $increment-1 ], $lessonnumber[ $increment-1
+ ], $lessontitle [ $increment-1 ],
       $startingpagenumber [ $increment-1 ] ) = $sth->fetchrow_array()
+;
}

$sth->finish;

$dbh->disconnect
    or warn "Disconnect failed: $DBI::errstr\n";

#for ( $increment = 1; $increment <= 132; $increment++ ) {
#    print ($lessonsimplename [ $increment ].": ".$lessontitle [ $incr
+ement ]." p. ".$startingpagenumber [ $increment ]."\n");
#}
        
sub new {
    my $ref = shift;
    my $self = $ref->SUPER::new( undef,           # parent window
                                 -1,              # ID -1 means any
                                 '********',      # title
                                 &Wx::wxDefaultPosition,      # defaul
+t position
                                 [200, 200]      # size
                                 );
    my $panel = Wx::Panel->new( $self,            # parent window
                                -1,               # ID
                                );
    my $button1 = Wx::Button->new( $panel,         # parent window
                                  -1,             # ID
                                  'Click me 1!',    # label
                                  [50, 20],       # position
                                  &Wx::wxDefaultSize       # default s
+ize
                                  );
    my $button2 = Wx::Button->new( $panel,         # parent window
                                  -1,             # ID
                                  'Click me 2!',    # label
                                  [50, 50],       # position
                                  &Wx::wxDefaultSize       # default s
+ize
                                  );

    my $button3 = Wx::Button->new( $panel,         # parent window
                                  -1,             # ID
                                  '*********',    # label
                                  [50, 80],       # position
                                  &Wx::wxDefaultSize       # default s
+ize
                                  );
    my $combobox1 = Wx::ComboBox->new( $panel,
                                      -1,
                                      $lessonsimplename[ 0 ],
                                      [50, 110],
                                      [-1, -1],
                                      \@lessonsimplename,
                                      0,
                                      &Wx::wxDefaultValidator,
                                      ''
                                      );
                                  
    EVT_BUTTON( $self, $button1, \&Button1Click );
    EVT_BUTTON( $self, $button2, \&Button2Click );
    EVT_BUTTON( $self, $button3, \&Button3Click );
    EVT_COMBOBOX( $self, $combobox1, \&Combobox1action );
    
    return $self;
}

sub Button1Click {
    my( $self, $event ) = @_;
    
    $self->SetTitle( 'Button 1 Clicked' );
}

sub Button2Click {
    my( $self, $event ) = @_;
    
    $self->SetTitle( 'Button 2 Clicked' );
}

sub Button3Click {
    my( $self, $event ) = @_;
           
    $self->SetTitle( '*********' );
}

sub Combobox1action {
    my( $self, $event ) = @_;

    $self->SetTitle( 'Combo box selected' );
}
[download]

Thanks.

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