NAME

Class::MVC - model-view-controller paradigma

SYNOPSIS

        use Class::Maker 'class';

        use Class::MVC;
        
        class 'Widget',
        {
                isa => [qw( Class::MVC )]
        };

        class 'Widget::ViewModel',
        {                       
                isa => [qw( Device::Output::Channel )],
                
                public =>
                {
                        string => [qw( info )],
                },
        };

        class 'Widget::Model',
        {
                isa => [qw( Class::MVC::Model Shell::Widget::ViewModel)],
        };

        class 'Widget::View',
        {
                isa => [qw( Class::MVC::CompositeView )],
                
                public =>
                {
                        ref => [qw( device )],
                },
        };

        class 'Widget::Controller',
        {
                isa => [qw( Class::MVC::Controller )],          
                
                public => 
                {
                        ref => [qw( sensor )],
                },
                
                default =>
                {
                        sensor => Device::Input->new(),
                },
        };

DESCRIPTION

The Model-View-Controller (MVC) is a general paradigma mostly used for GUI-development. It is very well known and tons of publications are available through your favorite search engine (Or jump to "REFERENCES"). It is also an introductional example from the famous "Design Patterns" book.

                            +------------+
                            |   Model    |
                            +------------+
                           /\ .          /\
                           / .            \
                          / .              \
                         / .                \
                        / \/                 \
                  +------------+ <------ +------------+
 Graphical  <==== |    View    |         | Controller |  <==== User Input
  Output          +------------+ ......> +------------+

Class::MVC::Model

This class is derived from Class::Observable (Class::Observable). Class::MVC::View's observe it to make appropriate changes to the presentation (aka View) if an update of the "Class::MVC::Model" happens.

[Note] Some publications prefer to separate a Data Model and a View Model. My personal preference tend to have a simple ViewModel class and let a DataModel class derive from Class::MVC::Model and our ViewModel class.

Class::MVC::View

model: Reference to a Class::MVC::Model object.
controller: Reference to a Class::MVC::Controller object.

Class::MVC::Model-notify_observers( 'update' )> will call a _on_update method of the observing View's.

[Note] Class::MVC::View is derived from Class::Listener to dispatch the observer notify to the _on_update method.

Class::MVC::CompositeView

This is the base class for nested views. A CompsiteView is a derived View. Its update() method takes the job to inform the super_view of sub_view changes changes.

See "REFERENCES".