.. index:: single: PHP Templates
Even if Symfony2 defaults to Twig for its template engine, you can still use plain PHP code if you want. Both templating engines are supported equally in Symfony2. Symfony2 adds some nice features on top of PHP to make writing templates with PHP more powerful.
If you want to use the PHP templating engine, first, make sure to enable it in your application configuration file:
.. configuration-block:: .. code-block:: yaml # app/config/config.yml framework: # ... templating: { engines: ['twig', 'php'] } .. code-block:: xml <!-- app/config/config.xml --> <framework:config ... > <!-- ... --> <framework:templating ... > <framework:engine id="twig" /> <framework:engine id="php" /> </framework:templating> </framework:config> .. code-block:: php $container->loadFromExtension('framework', array( // ... 'templating' => array( 'engines' => array('twig', 'php'), ), ));
You can now render a PHP template instead of a Twig one simply by using the
.php
extension in the template name instead of .twig
. The controller
below renders the index.html.php
template:
// src/Acme/HelloBundle/Controller/HelloController.php public function indexAction($name) { return $this->render('AcmeHelloBundle:Hello:index.html.php', array('name' => $name)); }
.. index:: single: Templating; Layout single: Layout
More often than not, templates in a project share common elements, like the well-known header and footer. In Symfony2, we like to think about this problem differently: a template can be decorated by another one.
The index.html.php
template is decorated by layout.html.php
, thanks to
the extend()
call:
<!-- src/Acme/HelloBundle/Resources/views/Hello/index.html.php -->
<?php $view->extend('AcmeHelloBundle::layout.html.php') ?>
Hello <?php echo $name ?>!
The AcmeHelloBundle::layout.html.php
notation sounds familiar, doesn't it? It
is the same notation used to reference a template. The ::
part simply
means that the controller element is empty, so the corresponding file is
directly stored under views/
.
Now, let's have a look at the layout.html.php
file:
<!-- src/Acme/HelloBundle/Resources/views/layout.html.php -->
<?php $view->extend('::base.html.php') ?>
<h1>Hello Application</h1>
<?php $view['slots']->output('_content') ?>
The layout is itself decorated by another one (::base.html.php
). Symfony2
supports multiple decoration levels: a layout can itself be decorated by
another one. When the bundle part of the template name is empty, views are
looked for in the app/Resources/views/
directory. This directory store
global views for your entire project:
<!-- app/Resources/views/base.html.php -->
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title><?php $view['slots']->output('title', 'Hello Application') ?></title>
</head>
<body>
<?php $view['slots']->output('_content') ?>
</body>
</html>
For both layouts, the $view['slots']->output('_content')
expression is
replaced by the content of the child template, index.html.php
and
layout.html.php
respectively (more on slots in the next section).
As you can see, Symfony2 provides methods on a mysterious $view
object. In
a template, the $view
variable is always available and refers to a special
object that provides a bunch of methods that makes the template engine tick.
.. index:: single: Templating; Slot single: Slot
A slot is a snippet of code, defined in a template, and reusable in any layout
decorating the template. In the index.html.php
template, define a
title
slot:
<!-- src/Acme/HelloBundle/Resources/views/Hello/index.html.php -->
<?php $view->extend('AcmeHelloBundle::layout.html.php') ?>
<?php $view['slots']->set('title', 'Hello World Application') ?>
Hello <?php echo $name ?>!
The base layout already has the code to output the title in the header:
<!-- app/Resources/views/base.html.php -->
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title><?php $view['slots']->output('title', 'Hello Application') ?></title>
</head>
The output()
method inserts the content of a slot and optionally takes a
default value if the slot is not defined. And _content
is just a special
slot that contains the rendered child template.
For large slots, there is also an extended syntax:
<?php $view['slots']->start('title') ?>
Some large amount of HTML
<?php $view['slots']->stop() ?>
.. index:: single: Templating; Include
The best way to share a snippet of template code is to define a template that can then be included into other templates.
Create a hello.html.php
template:
<!-- src/Acme/HelloBundle/Resources/views/Hello/hello.html.php -->
Hello <?php echo $name ?>!
And change the index.html.php
template to include it:
<!-- src/Acme/HelloBundle/Resources/views/Hello/index.html.php -->
<?php $view->extend('AcmeHelloBundle::layout.html.php') ?>
<?php echo $view->render('AcmeHelloBundle:Hello:hello.html.php', array('name' => $name)) ?>
The render()
method evaluates and returns the content of another template
(this is the exact same method as the one used in the controller).
.. index:: single: Templating; Embedding Pages
And what if you want to embed the result of another controller in a template? That's very useful when working with Ajax, or when the embedded template needs some variable not available in the main template.
If you create a fancy
action, and want to include it into the
index.html.php
template, simply use the following code:
<!-- src/Acme/HelloBundle/Resources/views/Hello/index.html.php -->
<?php echo $view['actions']->render('AcmeHelloBundle:Hello:fancy', array('name' => $name, 'color' => 'green')) ?>
Here, the AcmeHelloBundle:Hello:fancy
string refers to the fancy
action of the
Hello
controller:
// src/Acme/HelloBundle/Controller/HelloController.php class HelloController extends Controller { public function fancyAction($name, $color) { // create some object, based on the $color variable $object = ...; return $this->render('AcmeHelloBundle:Hello:fancy.html.php', array('name' => $name, 'object' => $object)); } // ... }
But where is the $view['actions']
array element defined? Like
$view['slots']
, it's called a template helper, and the next section tells
you more about those.
.. index:: single: Templating; Helpers
The Symfony2 templating system can be easily extended via helpers. Helpers are
PHP objects that provide features useful in a template context. actions
and
slots
are two of the built-in Symfony2 helpers.
Speaking of web applications, creating links between pages is a must. Instead
of hardcoding URLs in templates, the router
helper knows how to generate
URLs based on the routing configuration. That way, all your URLs can be easily
updated by changing the configuration:
<a href="<?php echo $view['router']->generate('hello', array('name' => 'Thomas')) ?>">
Greet Thomas!
</a>
The generate()
method takes the route name and an array of parameters as
arguments. The route name is the main key under which routes are referenced
and the parameters are the values of the placeholders defined in the route
pattern:
# src/Acme/HelloBundle/Resources/config/routing.yml
hello: # The route name
pattern: /hello/{name}
defaults: { _controller: AcmeHelloBundle:Hello:index }
What would the Internet be without images, JavaScripts, and stylesheets?
Symfony2 provides the assets
tag to deal with them easily:
<link href="<?php echo $view['assets']->getUrl('css/blog.css') ?>" rel="stylesheet" type="text/css" />
<img src="<?php echo $view['assets']->getUrl('images/logo.png') ?>" />
The assets
helper's main purpose is to make your application more
portable. Thanks to this helper, you can move the application root directory
anywhere under your web root directory without changing anything in your
template's code.
When using PHP templates, escape variables whenever they are displayed to the user:
<?php echo $view->escape($var) ?>
By default, the escape()
method assumes that the variable is outputted
within an HTML context. The second argument lets you change the context. For
instance, to output something in a JavaScript script, use the js
context:
<?php echo $view->escape($var, 'js') ?>