Dealing with Views in Phalcon Controllers

I am working on a newly created Phalcon project, and I don't really know how to actually use multiples views.

What is the entry point? I don't really know when each method in the controller is called, under which conditions, etc.

Where is the control flow defined? is it based in the name of the view? or is there a place where you can register them?

Solution

Phalcon is a bit different than other well-known PHP frameworks, in that not much is pre-configured or pre-built by default. It's quite loosely-coupled. So you have to decide where and how your control flow will work. This means that you will need to dig deeper in the documentation and also that there could be different way to achieve the same thing.

I'm going to walk you through a simple example and provide references, so you can understand it more.

1) You would start by defining a bootstrap file (or files) that will define the routes, or entry points, and will setup and create the application. This bootstrap file could be called by an index.php file that is the default file served by the web server. Here is an example of how such bootstrap file will define the routes or entry points (note: these are just fragments and do not represent all the things that a bootstrap file should do):

use Phalcon\Di\FactoryDefault;

// initializes the dependency injector of Phalcon framework
$injector = new FactoryDefault();

// defines the routes
$injector->setShared('router', function () {
    return require_once('some/path/routes.php');
});

Then it the routes.php file:

use Phalcon\Mvc\Router;
use Phalcon\Mvc\Router\Group as RouterGroup;

// instantiates the router
$router = new Router(false);
// defines routes for the 'users' controller
$user_routes = new RouterGroup(['controller' => 'users']);
$user_routes->setPrefix('/users');
$user_routes->addGet('/show/{id:[0-9]{1,9}}', ['action' => 'show']);
$router->mount($user_routes);
return $router;

Im defining routes in an alternate way, by defining routes groups. I find it to be more easy to organize routes by resource or controller.

2) When you enter the url example.com/users/show/123, the routes above will match this to the controller users and action show. This is specified by the chunks of code ['controller' => 'users'], setPrefix('/users') and '/show/{id:[0-9]{1,9}}', ['action' => 'show']

3) So now you create the controller. You create a file in, let's say, controllers/UsersController.php. And then you create its action; note the name that you used in the route (show) and the suffix of Action:

public function showAction(int $id) {
    // ... do all you need to do...

    // fetch data
    $user = UserModel::findFirst(blah blah);

    // pass data to view
    $this->view->setVar('user', $user);

    // Phalcon automatically calls the view; from the manual:
    /*
    Phalcon automatically passes the execution to the view component as soon as a particular
    controller has completed its cycle. The view component will look in the views folder for
    a folder named as the same name of the last controller executed and then for a file named
    as the last action executed.
    */

    // but in case you would need to specify a different one
    $this->view->render('users', 'another_view');
}

There is much more stuff related to views; consult the manual.

Note that you will need to register such controller in the bootstrap file like (Im also including examples on how to register other things):

use Phalcon\Loader;
// registers namespaces and other classes
$loader = new Loader();
$loader->registerNamespaces([
    'MyNameSpace\Controllers' => 'path/controllers/',
    'MyNameSpace\Models' => 'path/models/',
    'MyNameSpace\Views' => 'path/views/'
]);
$loader->register();

4) You will also need to register a few things for the views. In the bootstrap file

use Phalcon\Mvc\View;

$injector->setShared('view', function () {
    $view = new View();
    $view->setViewsDir('path/views/');
    return $view;
});

And this, together with other things you will need to do, particularly in the bootstrap process, will get you started in sending requests to the controller and action/view defined in the routes.

Those were basic examples. There is much more that you will need to learn, because I only gave you a few pieces to get you started. So here are some links that can explain more. Remember, there are several different ways to achieve the same thing in Phalcon.

Bootstrapping:

https://docs.phalconphp.com/en/3.2/di

https://docs.phalconphp.com/en/3.2/loader

https://docs.phalconphp.com/en/3.2/dispatcher

Routing: https://docs.phalconphp.com/en/3.2/routing

Controllers: https://docs.phalconphp.com/en/3.2/controllers

More on Views (from registering to passing data to them, to templating and more): https://docs.phalconphp.com/en/3.2/views

And a simple tutorial to teach you some basic things: https://docs.phalconphp.com/en/3.2/tutorial-rest