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=item *

pos 0 is the date format of the database.

=item * 

pos 1 is the format to display the date in the form. 

=back

C<time_zone> and C<locale> are needed by Date::Time::Strptime.



To display new rows on a bound subform, connect the on_change event to the field of the primary key in the main form.
In this sub, call a sub to synchonize the form:

In the main form:

    sub on_nofm_changed {
        my $widget = shift;
	my $self = shift;
	my $pk_value = $widget->get_text();
	$self->{subform_a}->synchronize_with($pk_value);
	...
	}

In the subform_a module

    sub synchronize_with {
	my ($self,$value) = @_;
	my $data = Rdb::Product::Manager->get_product(with_objects => ['seller_product'], query => ['seller_product.no_seller' => {eq => $value}]);
	$self->{subform_a}->get_data_manager->query($data);	
	$self->{subform_a}->update;
     }

=head2 Dealing with many to many relationship 

It's the sellers and products situation where a seller sells many products and a product is selled by many sellers.
One way is to have a insert statement that insert a new row in the linking table (named transaction for example) each time a new row is added in the product table.

An other way is to create a data manager for the transaction table

With DBI

	$dman = Gtk2::Ex::DbLinker::DbiDataManager->new( dbh => $self->{dbh}, sql =>{select =>"no_seller, no_product", from => "transaction", where => ""});

With Rose::DB::Object

	$data = Rdb::Transaction::Manager->get_transaction(query=> [no_seller => {eq => $current_seller }]);

	$dman = Gtk2::Ex::DbLinker::RdbDataManager->new(data => $data, meta=> Rdb::Transaction->meta);

And keep a reference of this for latter

      $self->{linking_data} = $dman;

If you want to link a new row in the table product with the current seller, create a method that is passed and array of primary key values for the current seller and the new product.

	sub update_linking_table {
	   	my ( $self, $keysref) = @_;
   		my @keys = keys %{$keysref};
		my $f =  $self->{main_form};
		my $dman = $self->{main_abo}->{linking_data};
		$dman->new_row;
		foreach my $k (@keys){
			my $value = ${$keysref}{$k};
			$dman->set_field($k, $value );
		}
		$dman->save;
	}

This method is to be called when a new row has been added to the product table:

	sub on_newproduct_applied_clicked {
		my $button = shift;
	 	my $self = shift;
    		my $main = $f->{main_form};
    		$self->{product}->apply;
		my %h;
		$h{no_seller}= $main->{no_seller};
		$h{no_product}= $self->{abo}->get_widget_value("no_product");
    		$self->update_linking_table(\%h);
	}

You may use the same method to delete a row from the linking table

	my $data = Rdb::Transaction::Manager->get_transaction(query=> [no_seller => {eq => $seller }, no_product=>{eq => $product } ] );
	$f->{linking_data}->query($data);
	$f->{linking_data}->delete;

=head1 DESCRIPTION

This module automates the process of tying data from a database to widgets on a Glade-generated form.
All that is required is that you name your widgets the same as the fields in your data source.

Steps for use:

=over

=item * 

Create a xxxDataManager object that contains the rows to display

=item * 

Create a Gtk2::GladeXML object (the form widget)

=item * 

Create a Gtk2::Ex::DbLinker::Form object that links the data and your form

=item *

You would then typically connect the buttons to the methods below to handle common actions
such as inserting, moving, deleting, etc.

=back

=head1 METHODS