X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FCatalyst%2FManual%2FTutorial%2FAdvancedCRUD.pod;h=96fb811de10ef52b81a7463ab5b0cb0765db2924;hb=936a5dd5c424d816dd470690473c1e38127a0c3c;hp=c68d6c846b26058f6039bbabb261dbe3e2339886;hpb=be16bacd7d5dcea0165355cb7bbd8a14c1af184e;p=catagits%2FCatalyst-Runtime.git

diff --git a/lib/Catalyst/Manual/Tutorial/AdvancedCRUD.pod b/lib/Catalyst/Manual/Tutorial/AdvancedCRUD.pod
index c68d6c8..96fb811 100644
--- a/lib/Catalyst/Manual/Tutorial/AdvancedCRUD.pod
+++ b/lib/Catalyst/Manual/Tutorial/AdvancedCRUD.pod
@@ -58,7 +58,7 @@ validation of user-entered data, and automated transfer of data between
 forms and model objects.
 
 In keeping with the Catalyst (and Perl) spirit of flexibility, there are
-many different ways approach advanced CRUD operations in a Catalyst
+many different ways to approach advanced CRUD operations in a Catalyst
 environment.  One alternative is to use
 L<Catalyst::Helper::Controller::Scaffold|Catalyst::Helper::Controller::Scaffold> 
 to instantly construct a set of Controller methods and templates for 
@@ -70,7 +70,7 @@ L<HTML::FillInForm|HTML::FillInForm>.
 
 Here, we will make use of the L<HTML::Widget|HTML::Widget> to not only 
 ease form creation, but to also provide validation of the submitted 
-data.  The approached used by the part of the tutorial is to slowly 
+data.  The approached used by this part of the tutorial is to slowly 
 incorporate additional L<HTML::Widget|HTML::Widget> functionality in a 
 step-wise fashion (we start with fairly simple form creation and then 
 move on to more complex and "magical" features such as validation and 
@@ -79,12 +79,7 @@ auto-population/auto-saving).
 B<Note:> Part 8 of the tutorial is optional.  Users who do not wish to
 use L<HTML::Widget|HTML::Widget> may skip this part.
 
-B<TIP>: Note that all of the code for this part of the tutorial can be
-pulled from the Catalyst Subversion repository in one step with the
-following command:
-
-    svn checkout http://dev.catalyst.perl.org/repos/Catalyst/trunk/examples/Tutorial@###
-    IMPORTANT: Does not work yet.  Will be completed for final version.
+You can checkout the source code for this example from the catalyst subversion repository as per the instructions in L<Catalyst::Manual::Tutorial::Intro>
 
 =head1 C<HTML::WIDGET> FORM CREATION
 
@@ -131,12 +126,12 @@ following method:
         return $w;
     }
 
-This method provides a central location (so it can be called by multiple
-actions, such as C<create> and C<edit>) that builds an HTML::Widget-based
-form with the appropriate fields. The "Get Authors" code uses DBIC to
-retrieve a list of model objects and then uses C<map> to create a hash
-where the hash keys are the database primary keys from the authors table
-and the associated values are the last names of the authors.
+This method provides a central location that builds an 
+HTML::Widget-based form with the appropriate fields.  The "Get authors" 
+code uses DBIC to retrieve a list of model objects and then uses C<map> 
+to create a hash where the hash keys are the database primary keys from 
+the authors table and the associated values are the last names of the 
+authors.
 
 =head2 Add Actions to Display and Save the Form
 
@@ -192,9 +187,9 @@ following methods:
         # Set a status message for the user
         $c->stash->{status_msg} = 'Book created';
     
-        # Use 'hw_create' to redisplay the form
+        # Use 'hw_create' to redisplay the form.  As discussed in 
+        # Part 3, 'detach' is like 'forward', but it does not return
         $c->detach('hw_create');
-    
     }
 
 Note how we use C<make_book_widget> to build the core parts of the form
@@ -430,6 +425,8 @@ now has a C<$c-E<gt>stash-E<gt>{template}> line).  Note that if we
 process the form in C<hw_create_do> I<and> forward/detach back to
 <hw_create>, we would end up with C<make_book_widget> being called
 twice, resulting in a duplicate set of elements being added to the form.
+(There are other ways to address the "duplicate form rendering" issue --
+just be aware that it exists.)
 
 =item *
 
@@ -449,7 +446,8 @@ similar to the prior version of the C<hw_create_do> method.
 
 =head2 Try Out the Form
 
-Press C<Ctrl-C> to kill the previous server instance (if it's still running) and restart it:
+Press C<Ctrl-C> to kill the previous server instance (if it's still 
+running) and restart it:
 
     $ script/myapp_server.pl
 
@@ -459,6 +457,7 @@ two, and zero authors.  When you click Submit, the HTML::Widget
 C<constraint> items will validate the logic and insert feedback as
 appropriate.
 
+
 =head1 Enable C<DBIx::Class::HTMLWidget> Support
 
 In this section we will take advantage of some of the "auto-population"
@@ -542,6 +541,9 @@ match the following code:
     
             # Set a status message for the user
             $c->stash->{status_msg} = 'Book created';
+            
+            # Redisplay an empty form for another
+            $c->stash->{widget_result} = $w->result;
         }
     
         # Set the template
@@ -554,7 +556,190 @@ C<$c-E<gt>model('MyAppDB::Book')-E<gt>create> and replaced it with a
 single call to C<$book-E<gt>populate_from_widget>.  Note that we still
 have to call C<$book-E<gt>add_to_book_authors> once per author because
 C<populate_from_widget> does not currently handle the relationships
-between tables.
+between tables.  Also, we reset the form to an empty fields by adding
+another call to C<$w-E<gt>result> and storing the output in the stash 
+(if we don't override the output from C<$w-E<gt>process($c-E<gt>req)>,
+the form values already entered will be retained on redisplay --
+although this could be desirable for some applications, we avoid it
+here to help avoid the creation of duplicate records).
+
+
+=head2 Try Out the Form
+
+Press C<Ctrl-C> to kill the previous server instance (if it's still 
+running) and restart it:
+
+    $ script/myapp_server.pl
+
+Try adding a book that validate.  Return to the book list and the book 
+you added should be visible.
+
+
+
+=head1 Rendering C<HTMLWidget> Forms in a Table
+
+Some developers my wish to use the "old-fashioned" table style of 
+rendering a form in lieu of the default C<HTML::Widget> rendering that 
+assumes you will use CSS for formatting.  This section demonstrates
+some techniques that can override the default rendering with a 
+custom class.
+
+
+=head2 Add a New "Element Container"
+
+Open C<lib/FormElementContainer.pm> in your editor and enter:
+
+    package FormElementContainer;
+    
+    use base 'HTML::Widget::Container';
+    
+    sub _build_element {
+        my ($self, $element) = @_;
+    
+        return () unless $element;
+        if (ref $element eq 'ARRAY') {
+            return map { $self->_build_element($_) } @{$element};
+        }
+        my $e = $element->clone;
+        $e = new HTML::Element('span', class => 'fields_with_errors')->push_content($e)
+            if $self->error && $e->tag eq 'input';
+    
+        return $e ? ($e) : ();
+    }
+    
+    1;
+
+This simply dumps the HTML code for a given form element, followed by a 
+C<span> that can contain validation error message.
+
+
+=head2 Enable the New Element Container When Building the Form
+
+Open C<lib/MyApp/Controller/Books.pm> in your editor.  First add a
+C<use> for your element container class:
+
+    use FormElementContainer;
+
+B<Note:> If you forget to C<use> your container class in your 
+controller, then your form will not be displayed and no error messages 
+will be generated. Don't forget this important step!
+
+Then tell C<HTML::Widget> to use that class during rendering by updating
+C<make_book_widget> to match the following:
+
+    sub make_book_widget {
+        my ($self, $c) = @_;
+    
+        # Create an HTML::Widget to build the form
+        my $w = $c->widget('book_form')->method('post');
+    
+        # ***New: Use custom class to render each element in the form    
+        $w->element_container_class('FormElementContainer');
+        
+        # Get authors
+        my @authorObjs = $c->model("MyAppDB::Author")->all();
+        my @authors = map {$_->id => $_->last_name }
+                           sort {$a->last_name cmp $b->last_name} @authorObjs;
+    
+        # Create the form feilds
+        $w->element('Textfield', 'title'  )->label('Title')->size(60);
+        $w->element('Textfield', 'rating' )->label('Rating')->size(1);
+        # Convert to multi-select list
+        $w->element('Select',    'authors')->label('Authors')
+            ->options(@authors)->multiple(1)->size(3);
+        $w->element('Submit',    'submit' )->value('submit');
+    
+        # Set constraints
+        $w->constraint(All     => qw/title rating authors/)
+            ->message('Required. ');
+        $w->constraint(Integer => qw/rating/)
+            ->message('Must be an integer. ');
+        $w->constraint(Range   => qw/rating/)->min(1)->max(5)
+            ->message('Must be a number between 1 and 5. ');
+        $w->constraint(Length  => qw/title/)->min(5)->max(50)
+            ->message('Must be between 5 and 50 characters. ');
+    
+        # Set filters
+        for my $column (qw/title rating authors/) {
+            $w->filter( HTMLEscape => $column );
+            $w->filter( TrimEdges  => $column );
+        }
+    
+        # Return the widget    
+        return $w;
+    }
+
+The two new lines are marked with C<***New:>.
+
+
+=head2 Update the TT Template
+
+Open C<root/src/books/hw_form.tt2> and edit it to match:
+
+    [% META title = 'Create/Update Book' %]
+    
+    [%# Comment out the auto-rendered form %]
+    [%# widget_result.as_xml %]
+    
+    
+    [%# Iterate over the form elements and display each -%]
+    <form name="book_form" action="[% widget_result.action %]" method="post">
+    <table border="0">
+    [% FOREACH element = widget_result.elements %]
+      <tr>
+        <td class="form-label">
+          [% element.label.as_text %]
+        </td>
+        <td class="form-element">
+          [% element.element_xml %]
+          <span class="form-error">
+            [% element.error_xml %]
+          </span>
+        </td>
+      </tr>
+    [% END %]
+    </table>
+    </form>
+    
+    
+    <p><a href="[% Catalyst.uri_for('list') %]">Return to book list</a></p>
+    
+    
+    [%# A little JavaScript to move the cursor to the first field %]
+    <script LANGUAGE="JavaScript">
+    document.book_form.book_form_title.focus();
+    </script>
+
+This represents three changes:
+
+=over 4
+
+=item *
+
+The existing C<widget_result.as_xml> has been commented out.
+
+=item *
+
+It loops through each form element, displaying the field name in the 
+first table cell along with the form element and validation errors in 
+the second field.
+
+=item *
+
+JavaScript to position the user's cursor in the first field of the form.
+
+=back
+
+
+=head2 Try Out the Form
+
+Press C<Ctrl-C> to kill the previous server instance (if it's still 
+running) and restart it:
+
+    $ script/myapp_server.pl
+
+Try adding a book that validate.  Return to the book list and the book 
+you added should be visible.
 
 
 =head1 AUTHOR
@@ -562,7 +747,7 @@ between tables.
 Kennedy Clark, C<hkclark@gmail.com>
 
 Please report any errors, issues or suggestions to the author.  The
-most recent version of the Catlayst Tutorial can be found at
+most recent version of the Catalyst Tutorial can be found at
 L<http://dev.catalyst.perl.org/repos/Catalyst/trunk/Catalyst-Runtime/lib/Catalyst/Manual/Tutorial/>.
 
 Copyright 2006, Kennedy Clark, under Creative Commons License