View¶
This is essential part of any web application which allows you easily show data using html templates and layouts.
Template¶
Templates usually used for displaying a part of a page. It would be like, a login page or list of users, etc.
Template example¶
<?php
use Tiny\View\View;
// we are going to show the user list
$view = new View(['users' => [
['id' => 1, 'name' => 'Tester1'],
['id' => 2, 'name' => 'Tester2']
]],
'./users.phtml' // a template for the data
);
// render the template using passed variables
echo $view;
And the HTML template (users.phtml):
<ul>
<?php foreach ($this->users as $user): ?>
<li>
<b><?= $this->id ?></b>: <?= $this->name ?>
</li>
<?php endforeach ?>
</ul>
Note: In HTML files you are free to use any PHP methods and operators.
Read more about the alternative syntax which is convenient way for using in templates: https://www.php.net/manual/en/control-structures.alternative-syntax.php
Layout¶
Layouts work as wrappers for generated content. In our case we may wrap the rendered users list in a layout (which may include js/css files, meta, etc). Usually there is a one universal layout and many templates but it optional.
Layout example¶
<?php
use Tiny\View\View;
$view = new View(['users' => [
['id' => 1, 'name' => 'Tester1'],
['id' => 2, 'name' => 'Tester2']
]],
'./users.phtml', // a template for the data
'./layout/base.phtml' // a layout for wrapping the data
);
// render both template and layout
echo $view;
And the HTML layout (base.phtml):
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>My test site</title>
</head>
<body>
<div class="container">
<!-- inject generated data from the templates -->
<?= $this->content ?>
</div>
</body>
</html>
View helpers¶
Some times it not enough only inject variables in templates/layouts or call inbuilt PHP functions.
We need to call our own functions in the template context.
To make it real the View uses the Event manager.
Generally speaking whenever you call an undefined method (which is not registered in the View object)
The View triggers an event which includes the invoked method’s name and its parameters,
and there is should be a listener which is responsible for that method.
In example bellow we implement a simple helper for printing a random value.
Helper example¶
<?php
use Tiny\EventManager\Event;
use Tiny\EventManager\EventManager;
use Tiny\ServiceManager\ServiceManager;
use Tiny\View\View;
// create a new event manager
$eventManager = new EventManager(
// the event manager requires the service manager (a service locator)
new ServiceManager([
'ViewHelperRandom' => function() { // register a new view helper service
return function(Event $event) {
// return a random value
$event->setData(rand());
}
}
])
);
// listen the any invocations of `$this->random()` in the View and call it from the service manager
$eventManager->subscribe('view.call.helper.random', 'ViewHelperRandom');
// init the View
$view = new View(['users' => [
['id' => 1, 'name' => 'Tester1'],
['id' => 2, 'name' => 'Tester2']
]],
'./users.phtml'
);
// register the event manager in the View
$view->setEventManager($eventManager);
// render the template using passed variables
echo $view;
The HTML template snippet:
<ul>
<?php foreach ($this->users as $user): ?>
<li>
<b><?= $this->random() ?></b>: <?= $this->name ?>
</li>
<?php endforeach ?>
</ul>