Behaviors are a fantastic tool for making things easy in the back-end. They introduce configurable and reusable patterns to base classes, such as models and controllers.

There are several behaviors that ship with October:

• Form Controller for creating, viewing, updating, deleting records
• List Controller for displaying a list of many records
• Relation Controller for handling relationships between records

Example controller that implements behaviors:

class Customers extends Controller
{
    public $implement = [
        'Backend.Behaviors.FormController',
        'Backend.Behaviors.ListController',
        'Backend.Behaviors.RelationController',
    ];

    public $formConfig = 'config_form.yaml';
    public $listConfig = 'config_list.yaml';
    public $relationConfig = 'config_relation.yaml';
}

These are all great for simple management of your data. Although sometimes you will encounter more complex situations where the demands are too much for these behaviors.

Here we'll show you how to get back to basics and follow the principals of MVC to get similar results. We will implement the controller behavior's logic by hand, starting with a basic back-end controller.

<?php namespace Acme\Formist\Controllers;

use Backend\Classes\Controller;

class MyController extends Controller
{
    // Methods are defined in here
}

In October the back-end routing follows the pattern of the controller, so the above class Acme\Formist\Controllers\MyController will have a URL route prefix of /backend/acme/formist/mycontroller.

The default entry point for a controller is defined by the index method, called an "action". This method can return content directly:

public function index()
{
    // Return a simple string
    return 'Home';
}

Or it might like to return a redirect to another page. This example redirects to the same controller with the helloworld action instead.

public function index()
{
    // Return a redirect
    return \Backend::redirect('acme/formist/mycontroller/helloworld');
}

Let's define the helloworld action method.

public function helloworld()
{
    // ...
}

When an action doesn't return anything, October will look for a view file with the same name as the action. In this case the file plugins/acme/formist/controllers/mycontroller/helloworld.htm is used for the content.

<h1>Hello world!</h1>

If an action takes parameters, these will be accepted as part of the URL, following the action name. This action uses the URL structure of /backend/acme/formist/mycontroller/update/6 passing "6" as the $id value.

public function update($id = null)
{
    return 'You gave an ID of: ' . $id;
}

Variables can be passed to the view file using the $this->vars property. So let's pass the ID as a variable called myId to the view.

public function update($id = null)
{
    $this->vars['myId'] = $id;
}

Now we can access it in the matching plugins/acme/formist/controllers/mycontroller/update.htm file as the $myId variable.

<p>You gave an ID of: <?= $myId ?></p>

You can specify as many parameters as you like, they will be added to the URL accordingly. Here we add a context parameter to make the URL /backend/acme/formist/mycontroller/update/6/foobar passing "6" to $id and "foobar" to $context.

public function update($id = null, $context = null)
{
}

Controllers can also specify AJAX handlers, making dynamic page updates a breeze. These methods should always be specified as onSomething, here we will specify a handler called onUpdate.

public function onUpdate()
{
    // ...
}

To make an AJAX handler available only to a specific action, you may prefix it with the action name. This onUpdate AJAX handler can only be called from the update action.

public function update_onUpdate()
{
    // ...
}

In either case, the AJAX method will look at the URL for parameters, just like an action would. Let's write something to the trace log file using the trace_log() method and show a nice flash message.

public function onUpdate($id = null)
{
    // Check storage/logs/system.log
    trace_log('onUpdate was called with ID: '. $id);

    \Flash::success('Jobs done!');
}

Calling an AJAX handler is simple, let's do it from the update.htm view file.

<p>You gave an ID of: <?= $myId ?></p>

<button data-request="onUpdate">Write to log</button>

At the end of the storage/logs/system.log file we should see our trace log entry.

[2017-01-14 20:12:56] dev.INFO:  onUpdate was called with ID: 6

View the next part in the series Rendering Lists and Forms by hand.