SNotifications

Inspired by Apple's NSNotificationCenter library, this class is a very simple version of it. Consumers can set observers for specific notification event names. Every time a notification is posted through this class, observers for the given event name will be sent a SNotification class instance containing any passed data.

SNotifications is meant to be a simple solution for decoupling code. This can help reduce hard dependencies between code modules.

If you're using Yii Framework, an application component class SNotificationsComponent is also available in this package.

This requires PHP 5.3+

Usage

1. Create an instance of SNotifications that can be accessed by all your classes. PHP best practices recommend this to be inside a class.

    require('SNotifications.php');
   
    class MyGlobals 
    {
      public static $notifications = new SNotifications();
    }
   

2. Add observers for your event names.

    MyGlobals::$notifications->addObserver('new-user-created', 
      array('UserDataStorage', 'onNewUserCreatedNotification'));
   

3. Observers must be able to receive a SNotification class.

    class UserDataStorage
    {
      public static onNewUserCreatedNotification($notification)
      {
        // Notification senders can pass additional data. In here, we're expecting 
        // senders of the `new-user-created` event to pass in the userId
        $userId = $notification->getDataItem('userId', null);
        // do something with userId
      }
    }
   

4. Somewhere in your code, post notifications.

    // post a `new-user-created` event with a `userId` data item 
    MyGlobals::$notifications->post('new-user-created', array('userId' => '<a-user-id>'));
   

Usage (Yii Framework)

There is a Yii Framework application component class named SNotificationsComponent included in the package. The class allows setting of observers in the configuration file. It also provides a static instance of SNotifications for convenience.

To set it up, just declare the component in the Yii configuration file under components:

'components' => array(
  ...

  'notifications' => array(
    'class' => 'ext.snotifications.SNotificationsComponent',
    'observers' => array(
      'new-user-created' => array(
        array('UserDataStorage', 'onNewUserCreatedNotification')
      ),
      // other events here
    ),
  )      

  ...
)

To post notifications, use the getDefault method for getting the SNotifications instance:

Yii::app()->notifications->getDefault()->post('new-user-created', 
  array('userId' => '<a-user-id>'));