Ajax

• Basic usage
  • Example
• Themosis Global Object
  • Customize object name
  • WordPress localize

Basic usage

The Ajax class handles the WordPress mechanism for easily handling ajax requests.

In order to listen to a WordPress ajax action, use the listen method:

Ajax::listen('my_action', function() {  
    // Perform security check before anything - nonce
    $value = $_POST['key'];

    // Perform your WordPress actions...
});

The previously defined method run() is now deprecated.

Here are the method details:

Ajax::listen($action, $callback, $logged);

• $action string: Your custom action name for the Ajax request.
• $callback string: A callback function where you run your custom code.
• $logged callback: Possible values are true, false, both. You tell if the ajax action should be performed for logged in(true) or logged out(false) users or both.

The new listen() swapped the $callback and $logged parameters.

Example:

The code below shows a simple AJAX process. It uses a Javascript and a PHP files. Check the comments in the code for more tips/hints.

// This file is stored in assets/js/application.js
// Let's assume this ajax request is made when a user click a button.
// When the ajax request is done, we simply display it in the console.
$.ajax({
    url: themosis.ajaxurl, // Global access to the WordPress ajax handler file
    type: 'POST',
    dataType: 'json',
    data: {
        action: 'my-custom-action', // Your custom hook/action name
        security: 'add-posts', // A nonce value
        number: 2 // The value you want to send
    }
}).done(function(data)
{   
    // This should print "4" in the console.
    console.log(data);
});

Now that the user has clicked the button and ran the ajax request. Let's handle it with our Ajax class.

<?php
    // This file is stored in resources/admin/ajax.php
    // This code listens for logged in and logged out users
    Ajax::listen('my-custom-action', function(){    
        // Check nonce value
        check_ajax_referer('add-posts', 'security');

        // Run custom code - Make sure to sanitize and check values before
        $result = 2 + $_POST['number'];

        // "Return" the result
        echo $result;

        // Close
        die();
    });
?>

Themosis Global Object

In the previous javascript example, we get access to some values using the following syntax:

{
    url: themosis.ajaxurl
}

This themosis global JSON object is located at the end of the closing </head> tag of any pages. By default, it contains the key/value pair ajaxurl but you can easily add more key/value pairs to this global object and access them in your code.

Note: This object is only available if you have installed a themosis-theme theme.

To add more values, you need to use the themosisGlobalObject filter like so:

Filter::add('themosisGlobalObject', function($data) {
    $data['myData'] = 'Some value';
    return $data;
});

This will output the following object:

var themosis = {
    ajaxurl = 'http://www.my-domain.com/wp-admin/admin-ajax.php',
    myData = 'Some value'
};

Customize object name

You can easily change the variable name of this global object. In order to do so, open the resources/config/theme.config.php file and change the namespace value:

[
    'namespace' => 'themosis' // Change this value...
]

WordPress localize

If you need JS properties for use inside your scripts, please check the asset guide and the localize method.