Add-on Packages¶

An add-on allows for the easy distribution of complete sets of resources in a single directory, complete with its own libraries, models, helpers, config, and language files. The following is an example of a directory for an add-on named “Foo Bar”

/system/user/addons/foo_bar
├─ config/
├─ helpers/
├─ language/
├─ libraries/
└─ models/

Whatever the purpose of the “Foo Bar” add-on, it can have its own config files, helpers, language files, libraries, and models.

Class Reference¶

class EE_Loader¶

EE_Loader::library($library[, $params = NULL[, $object_name = NULL]])¶

Parameters:	$library (mixed) – Library name as a string or an array with multiple libraries $params (array) – Optional array of parameters to pass to the loaded library’s constructor $object_name (string) – Optional object name to assign the library to
Returns:	EE_Loader instance (method chaining)
Return type:	EE_Loader

This method is used to load core classes.

Note

We use the terms “class” and “library” interchangeably.

For example, if you would like to send email with your add-on, the first step is to load the email class within your controller:

ee()->load->library('email');

Once loaded, the library will be ready for use, using ee()->email.

Library files can be stored in subdirectories within the main “libraries” directory, or within your personal application/libraries directory. To load a file located in a subdirectory, simply include the path, relative to the “libraries” directory. For example, if you have file located at:

libraries/flavors/Chocolate.php

You will load it using:

ee()->load->library('flavors/chocolate');

You may nest the file in as many subdirectories as you want.

Additionally, multiple libraries can be loaded at the same time by passing an array of libraries to the load method:

ee()->load->library(array('email', 'table'));

Setting options

The second (optional) parameter allows you to optionally pass configuration setting. You will typically pass these as an array:

$config = array(
        'mailtype' => 'html',
        'charset'  => 'utf-8',
        'priority' => '1'
);

ee()->load->library('email', $config);

Config options can usually also be set via a config file. Each library is explained in detail in its own page, so please read the information regarding each one you would like to use.

Please take note, when multiple libraries are supplied in an array for the first parameter, each will receive the same parameter information.

Assigning a Library to a different object name

If the third (optional) parameter is blank, the library will usually be assigned to an object with the same name as the library. For example, if the library is named Calendar, it will be assigned to a variable named ee()->calendar.

If you prefer to set your own class names you can pass its value to the third parameter:

ee()->load->library('calendar', NULL, 'my_calendar');

// Calendar class is now accessed using:
ee()->my_calendar

Please take note, when multiple libraries are supplied in an array for the first parameter, this parameter is discarded.

EE_Loader::driver($library[, $params = NULL[, $object_name]])¶

Parameters:	$library (mixed) – Library name as a string or an array with multiple libraries $params (array) – Optional array of parameters to pass to the loaded library’s constructor $object_name (string) – Optional object name to assign the library to
Returns:	EE_Loader instance (method chaining)
Return type:	EE_Loader

This method is used to load driver libraries, acts very much like the library() method.

As an example, if you would like to use sessions with your add-on, the first step is to load the session driver within your controller:

ee()->load->driver('session');

Once loaded, the library will be ready for use, using ee()->session.

Driver files must be stored in a subdirectory within the main “libraries” directory, or within your personal application/libraries directory. The subdirectory must match the parent class name. Read the Drivers description for details.

Additionally, multiple driver libraries can be loaded at the same time by passing an array of drivers to the load method:

ee()->load->driver(array('session', 'cache'));

Setting options

The second (optional) parameter allows you to optionally pass configuration settings. You will typically pass these as an array:

$config = array(
        'sess_driver' => 'cookie',
        'sess_encrypt_cookie'  => true,
        'encryption_key' => 'mysecretkey'
);

ee()->load->driver('session', $config);

Config options can usually also be set via a config file. Each library is explained in detail in its own page, so please read the information regarding each one you would like to use.

Assigning a Driver to a different object name

If the third (optional) parameter is blank, the library will be assigned to an object with the same name as the parent class. For example, if the library is named Session, it will be assigned to a variable named ee()->session.

If you prefer to set your own class names you can pass its value to the third parameter:

ee()->load->library('session', '', 'my_session');

// Session class is now accessed using:
ee()->my_session

EE_Loader::view($view[, $vars = array()[, return = FALSE]])¶

Parameters:	$view (string) – View name $vars (array) – An associative array of variables $return (bool) – Whether to return the loaded view
Returns:	View content string if $return is set to TRUE, otherwise EE_Loader instance (method chaining)
Return type:	mixed

This method is used to load your View files. If you haven’t read the Views section of the user guide it is recommended that you do since it shows you how this method is typically used.

The first parameter is required. It is the name of the view file you would like to load.

Note

The .php file extension does not need to be specified unless you use something other than .php.

The second optional parameter can take an associative array or an object as input, which it runs through the PHP extract() function to convert to variables that can be used in your view files. Again, read the Views page to learn how this might be useful.

The third optional parameter lets you change the behavior of the method so that it returns data as a string rather than sending it to your browser. This can be useful if you want to process the data in some way. If you set the parameter to TRUE (boolean) it will return data. The default behavior is FALSE, which sends it to your browser. Remember to assign it to a variable if you want the data returned:

$string = ee()->load->view('myfile', '', TRUE);

EE_Loader::vars($vars[, $val = ''])¶

Parameters:	$vars (mixed) – An array of variables or a single variable name $val (mixed) – Optional variable value
Returns:	EE_Loader instance (method chaining)
Return type:	EE_Loader

This method takes an associative array as input and generates variables using the PHP extract() function. This method produces the same result as using the second parameter of the ee()->load->view() method above. The reason you might want to use this method independently is if you would like to set some global variables in the constructor of your controller and have them become available in any view file loaded from any method. You can have multiple calls to this method. The data get cached and merged into one array for conversion to variables.

EE_Loader::get_var($key)¶

Parameters:	$key (string) – Variable name key
Returns:	Value if key is found, NULL if not
Return type:	mixed

This method checks the associative array of variables available to your views. This is useful if for any reason a var is set in a library or another controller method using ee()->load->vars().

EE_Loader::get_vars()¶

Returns:	An array of all assigned view variables
Return type:	array

This method retrieves all variables available to your views.

EE_Loader::clear_vars()¶

Returns:	EE_Loader instance (method chaining)
Return type:	EE_Loader

Clears cached view variables.

EE_Loader::model($model[, $name = ''[, $db_conn = FALSE]])¶

Parameters:	$model (mixed) – Model name or an array containing multiple models $name (string) – Optional object name to assign the model to $db_conn (string) – Optional database configuration group to load
Returns:	EE_Loader instance (method chaining)
Return type:	EE_Loader

ee()->load->model('model_name');

If your model is located in a subdirectory, include the relative path from your models directory. For example, if you have a model located at application/models/blog/Queries.php you’ll load it using:

ee()->load->model('blog/queries');

If you would like your model assigned to a different object name you can specify it via the second parameter of the loading method:

ee()->load->model('model_name', 'fubar');
ee()->fubar->method();

EE_Loader::database([$params = ''[, $return = FALSE[, $query_builder = NULL]]])¶

Parameters:	$params (mixed) – Database group name or configuration options $return (bool) – Whether to return the loaded database object $query_builder (bool) – Whether to load the Query Builder
Returns:	Loaded CI_DB instance or FALSE on failure if $return is set to TRUE, otherwise EE_Loader instance (method chaining)
Return type:	mixed

This method lets you load the database class. The two parameters are optional. Please see the database section for more info.

EE_Loader::dbforge([$db = NULL[, $return = FALSE]])¶

Parameters:	$db (object) – Database object $return (bool) – Whether to return the Database Forge instance
Returns:	Loaded CI_DB_forge instance if $return is set to TRUE, otherwise EE_Loader instance (method chaining)
Return type:	mixed

Loads the Database Forge class, please refer to that manual for more info.

EE_Loader::dbutil([$db = NULL[, $return = FALSE]])¶

Parameters:	$db (object) – Database object $return (bool) – Whether to return the Database Utilities instance
Returns:	Loaded CI_DB_utility instance if $return is set to TRUE, otherwise EE_Loader instance (method chaining)
Return type:	mixed

Loads the Database Utilities class, please refer to that manual for more info.

EE_Loader::helper($helpers)¶

Parameters:	$helpers (mixed) – Helper name as a string or an array containing multiple helpers
Returns:	EE_Loader instance (method chaining)
Return type:	EE_Loader

This method loads helper files, where file_name is the name of the file, without the _helper.php extension.

EE_Loader::file($path[, $return = FALSE])¶

Parameters:	$path (string) – File path $return (bool) – Whether to return the loaded file
Returns:	File contents if $return is set to TRUE, otherwise EE_Loader instance (method chaining)
Return type:	mixed

This is a generic file loading method. Supply the filepath and name in the first parameter and it will open and read the file. By default the data is sent to your browser, just like a View file, but if you set the second parameter to boolean TRUE it will instead return the data as a string.

EE_Loader::language($files[, $lang = ''])¶

Parameters:	$files (mixed) – Language file name or an array of multiple language files $lang (string) – Language name
Returns:	EE_Loader instance (method chaining)
Return type:	EE_Loader

This method is an alias of Language::loadfile().

EE_Loader::config($file[, $use_sections = FALSE[, $fail_gracefully = FALSE]])¶

Parameters:	$file (string) – Configuration file name $use_sections (bool) – Whether configuration values should be loaded into their own section $fail_gracefully (bool) – Whether to just return FALSE in case of failure
Returns:	TRUE on success, FALSE on failure
Return type:	bool

This method is an alias of EE_Config::load().

EE_Loader::is_loaded($class)¶

Parameters:	$class (string) – Class name
Returns:	Singleton property name if found, FALSE if not
Return type:	mixed

Allows you to check if a class has already been loaded or not.

Note

The word “class” here refers to libraries and drivers.

If the requested class has been loaded, the method returns its assigned name in the ee() object and FALSE if it’s not:

ee()->load->library('form_validation');
ee()->load->is_loaded('Form_validation');       // returns 'form_validation'

ee()->load->is_loaded('Nonexistent_library');   // returns FALSE

Important

If you have more than one instance of a class (assigned to different properties), then the first one will be returned.

ee()->load->library('form_validation', $config, 'fv');
ee()->load->library('form_validation');

ee()->load->is_loaded('Form_validation');       // returns 'fv'

EE_Loader::add_package_path($path[, $view_cascade = TRUE])¶

Parameters:	$path (string) – Path to add $view_cascade (bool) – Whether to use cascading views
Returns:	EE_Loader instance (method chaining)
Return type:	EE_Loader

Adding a package path instructs the Loader class to prepend a given path for subsequent requests for resources. As an example, the “Foo Bar” application package above has a library named Foo_bar.php. In our controller, we’d do the following:

ee()->load->add_package_path(APPPATH.'addons/foo_bar/')
        ->library('foo_bar');

EE_Loader::remove_package_path([$path = ''])¶

Parameters:	$path (string) – Path to remove
Returns:	EE_Loader instance (method chaining)
Return type:	EE_Loader

When your controller is finished using resources from an application package, and particularly if you have other application packages you want to work with, you may wish to remove the package path so the Loader no longer looks in that directory for resources. To remove the last path added, simply call the method with no parameters.

Or to remove a specific package path, specify the same path previously given to add_package_path() for a package.:

ee()->load->remove_package_path(APPPATH.'addons/foo_bar/');

EE_Loader::get_package_paths([$include_base = TRUE])¶

Parameters:	$include_base (bool) – Whether to include BASEPATH
Returns:	An array of package paths
Return type:	array

Returns all currently available package paths.