As one of the three pillars of the Model-View-Controller design pattern, the `View` class
(along with other supporting classes) is responsible for taking the data passed from the
request and/or controller, inserting this into the requested template/layout, and then returning
the rendered content.
The `View` class interacts with a variety of other classes in order to achieve maximum
flexibility and configurability at all points in the view rendering and presentation
process. The `Loader` class is tasked with locating and reading template files which are then
passed to the `Renderer` adapter subclass.
In the default configuration, the `File` adapter acts as both renderer and loader, loading files
from paths defined in _process steps_ (described below) and rendering them as plain PHP files,
augmented with [special syntax](../template).
The `View` class operates on _processes_, which define the steps to render a completed view. For
example, the default process, which renders a template wrapped in a layout, is comprised of two
_steps_: the first step renders the main template and captures it to the rendering context, where
it is embedded in the layout in the second step. See the `$_steps` and `$_processes` properties
for more information.
Using steps and processes, you can create rendering scenarios to suit very complex needs.
By default, the `View` class is called during the course of the framework's dispatch cycle by the
`Media` class. However, it is also possible to instantiate and call `View` directly, in cases
where you wish to bypass all other parts of the framework and simply return rendered content.
A simple example, using the `Simple` renderer/loader for string templates:
{{{
$view = new View(array('loader' => 'Simple', 'renderer' => 'Simple'));
echo $view->render('element', array('name' => "Robert"), array('element' => 'Hello, {:name}!'));
// Output:
"Hello, Robert!";
}}}
_Note_: This is easily adapted for XML templating.
Another example, this time of something that could be used in an application
error handler:
{{{
$view = new View(array(
'paths' => array(
'template' => '{:library}/views/errors/{:template}.{:type}.php',
'layout' => '{:library}/views/layouts/{:layout}.{:type}.php',
)
));
$page = $View->render('all', array('content' => $info), array(
'template' => '404',
'layout' => 'error'
));
}}}
To learn more about processes and process steps, see the `$_processes` and `$_steps` properties,
respectively.