Developing a module or plugin for VirtueMart 2

Documentation for the VirtueMart 2 API : http://docs.virtuemart.net/api-vm2
When you want to develop your own extension for VirtueMart, then these hints should help you get started:

Use
if (!class_exists( 'VmConfig' )) require(JPATH_ADMINISTRATOR.DS.'components'.DS.'com_virtuemart'.DS.'helpers'.DS.'config.php');
to load the configuration object in your extension. Now you have loaded the main API of VirtueMart 2. To be sure that the vm config is loaded, you may use

$config = VmConfig::loadConfig();

You can then easily access them with

VmConfig::get('yourVariable','default');

After loading the VmConfig you should always use the vm path constants to access files

JPATH_VM_SITE = JPATH_ROOT.DS.'components'.DS.'com_virtuemart' );
JPATH_VM_ADMINISTRATOR = JPATH_ROOT.DS.'administrator'.DS.'components'.DS.'com_virtuemart' );

For performance reasons you should always use the

if (!class_exists( 'MyClass' )) require (JPATH_VM_ADMINISTRATOR.DS....)

construction, dont use require_once

Loading and instancing a model is very easy in Vm, just use

$mynameModel = VmModel::getModel('myname');

for example: $currencyModel = VmModel::getModel('currency');

When you want to access the js used in vm then load them with

$config->jQuery();
$config->jVm();

or for the css use
$config->cssSite();

adding Virtuemart 2 menu to your component
IN view.php.html use
-----------------------------
if(!class_exists('VmView'))require(JPATH_VM_ADMINISTRATOR.DS.'helpers'.DS.'vmview.php');
class vmg_exportViewCategory extends VmView
-----------------------------

in tmpl/default.php for eg.

before your HTML codes
-----------------------------
$lang = JFactory::getLanguage();
$extension = 'com_virtuemart';
$base_dir = JPATH_ADMINISTRATOR;
$lang->load($extension, $base_dir);
AdminUIHelper::startAdminArea();

-----------------------------

After your HTML codes
-----------------------------
AdminUIHelper::endAdminArea();
----------------------------- *

to use vm2 tables

JTable::addIncludePath(JPATH_VM_ADMINISTRATOR.DS.'tables');

Adding an entry to Virtuemart menu
ON your installation SQL
INSERT INTO `#__virtuemart_adminmenuentries` (`id`, `module_id`, `parent_id`, `name`, `link`, `depends`, `icon_class`, `ordering`, `published`, `tooltip`, `view`, `task`) VALUES
(null, 77, 0, 'COM_MYCOMPONENT', 'index.php?option=com_mycomponent', '', 'vmicon vmicon-16-to_do_list_cheked_1', 2, 1, '', 'myview', 'mytask');

This example add an entry in 'tool' menu (module_id 77) with icon vmicon-16-to_do_list_cheked_1
result link is : index?option=com_mycomponent&view=myview&task=mytask

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