Magento 2 Preferences is used by the Magento 2 object manager to extend the default implementation. You can use preferences in Magento 2 to implement some interfaces or to rewrite/override the existing PHP classes and their methods.
In this article, you'll learn how to do it and discover useful examples that will help you along the way.
Magento 2 Object Manager is a PHP class responsible for creating and retrieving objects in Magento 2. It also manages to create factories and proxies.
To get the object manager instance use the code:
<?php
$objectManager = \Magento\Framework\App\ObjectManager::getInstance();
To add object Manager to constructor:
/
* @var \Magento\Framework\ObjectManagerInterface
*/
private $objectManager;
/
* @param \Magento\Framework\ObjectManagerInterface $objectmanager
*/
public function __construct(
\Magento\Framework\ObjectManagerInterface $objectmanager
) {
$this->objectManager = $objectmanager;
}
Using the ObjectManager you can get a singleton object (method "get") of PHP class or create a new one (method "create").
Example:
<?php
$objectManager = \Magento\Framework\App\ObjectManager::getInstance();
Creating configurable products you just` create simple products with some configurable options for customers to choose from. So, to create a configurable product programmatically you should start by creating a simple product and then assigning some features to it.
Follow these steps to create a configurable product in Magento 2 programmatically:
Magento 2 being a multifunctional e-commerce platform allows you to create products from the admin panel. There are plenty of options to fill out to create a simple product in Magento 2, which obviously takes some time.
And what if you have to create a huge amount of products, especially during the development or testing?
The easiest, in this case, would be to create products programmatically. And that is exactly what you're going to learn in this article.
Use the following method to create a simple product in Magento 2 programmatically:
getObjectManager();
$state = $objectManager->get('\Magento\Framework\App\State');
$state->setAreaCode('frontend');
Magento has developed several certificates for Magento 2, one of which is — Magento 2 Certified Professional Developer.
To get this certificate, you need to take an exam to test your knowledge and skills required to modify Magento 2 in the following areas: user interface, databases, admin panel, ordering process, catalog and extensions functionality.
The Magento 2 Developer Exam is for those who have a deep understanding of the Magento concepts and experience of developing Magento 2. It is recommended that you have not less than 1.5 years of experience in customizing Magento 2 before applying for the exam.
The exam consists of 60 single and multiple choices questions in English. The duration time is 90 minutes (1.5 hour). To successfully pass the exam you need to receive 64% or higher.
In this article, we will walk you through the low-cost options to prepare for the Magento 2 Certification without courses such as, for example, Magento U for $ 950.
Magento 2 is a complex unity of features that help you to build a successful, easily-manageable store. There are a lot of processes to be handled in Magento 2 admin that require automation and scheduling. And that is exactly where cron job comes in handy. So...
Let's find out what exactly is it, why you need it and how to create custom cron job in Magento 2.
Magento cron job — is one of the most important Magento 2 features. It helps to configure commands or script that systematically runs and performs the tasks you intend it to.
With the cron job you don't need to manually reindex, generate google sitemaps, send Magento emails, update currency rates etc. The cron job does it all for you automatically, on a specific date and time if you configure it correctly.
Sometimes you need to run Magento 2 code externally, in the following cases:
Now, Magento 2 has the plugins, interceptors, which allow you to execute your own code before/after calling the public class method.
1. Create the etc/di.xml file in your module folder and add the following code there:
<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
<type name="VendorName\ModuleName\Foder\SomeModel">
<plugin name="mycompany_mymodule_plugin_modulename_foder_somemodel"
type="MyCompany\MyModule\Plugin\ModuleName\Foder\SomeModelPlugin" sortOrder="10" />
</type>
</config>
In the previous article you learned how to create new tables in Magento 2 database. In this one, you will learn more about the models used to work with the Magento 2 database which allows you to read, edit and delete the data.
Magento 2 and Magento 1 uses the Model/ResourceModel/Collection ORM (Object-relational mapping) for these purposes. To implement this concept you need to create 3 files (model, resource model, collection).
When developing an online store based on Magento 2, you might face the problem of extending the standard Magento 2 or Magento 2 extensions functionality.
Editing Magento core files or modules is not allowed because these changes will be overwritten during the upgrade.
So, how to make changes to the storefront (frontend) template file, css, js?
WARNING! The following instructions cannot be used to override the layout files.
Let's say you need to change this file:
app/code/Magefan/Blog/view/frontend/templates/post/view.phtml
Make its copy in the theme folder with the following path:
app/design/frontend/ThemeVendor/themename/Magefan_Blog/templates/post/view.phtml
Make the necessary changes to the newly created theme file.
If your own theme is missing from your Magento installation, create new theme.
If you want to change product attribute type from dropdown to text in Magento 2, all you need to do is to run the following SQL queries (please make a Database backup before execution):
1. This query will change the attribute settings and convert it to a text attribute.
UPDATE eav_attribute SET
backend_type = "varchar",
frontend_input = "text",
source_model = ""
WHERE attribute_code = "MY_ATTRIBUTE_CODE";
2. This query will copy dropdown attribute data to the text attribute value table and replace the option IDs with their actual labels (text).
INSERT INTO catalog_product_entity_varchar
SELECT null as value_id, pei.attribute_id, pei.store_id, pei.entity_id, aov.value as value
FROM catalog_product_entity_int pei
LEFT JOIN eav_attribute_option ao ON pei.attribute_id = ao.attribute_id
LEFT JOIN eav_attribute_option_value aov ON ao.option_id = aov.option_id
WHERE
pei.value IS NOT NULL
AND pei.attribute_id
Sometimes, during Magento 2 customization you need to get the store Information programmatically. You may need to get a current Store ID, Store Code, Name, Website ID, or current URL.
To retrieve this data use the singleton instance of the following class:
\Magento\Store\Model\StoreManagerInterface
For example, you can include it in your class constructor and then call:
<?php
namespace \MyCompany\ExampleModule\Model;
class Example
{
private $storeManager;
public function __construct( ... \Magento\Store\Model\StoreManagerInterface $storeManager, ... ) {
... $this->storeManager = $storeManager; ... } /**
* Examples
*/
1. Get URL of the store homepage (http://domain.com/):
<?= $this->getUrl() ?>
2. Get URL of some page, e.g. "Contact Us" (http://domain.com/contacts/):
<?= $this->getUrl('contacts') ?>
3. Get URL of the theme static file, e.g.:
app/design/frontend/ThemeVendor/theme_name/web/css/custom.css
app/design/frontend/ThemeVendor/theme_name/Magefan_Blog/web/js/lazyload.js
app/code/Magefan_Blog/view/frontend/web/js/lazyload.js
vendor/magefan/module-blog/view/frontend/web/js/lazyload.js
use the following code:
<?= $this->getViewFileUrl('css/custom.css') ?>
<?= $this->getViewFileUrl('Magefan_Blog::js/lazyload.js') ?>
Menu Title [identifier]
Dashboard [Magento_Backend::dashboard]
Sales [Magento_Sales::sales] Operations [Magento_Sales::sales_operation] Orders [Magento_Sales::sales_order] Invoices [Magento_Sales::sales_invoice] Shipments [Magento_Sales::sales_shipment] Credit Memos [Magento_Sales::sales_creditmemo] Billing Agreements [Magento_Paypal::paypal_billing_agreement] Transactions [Magento_Sales::sales_transactions]
The etc/adminhtml/menu.xml file is used to control the Magento 2 admin panel menu and add new items to it, in particular.
In the previous article we described how to create your own section on the Magento 2 configuration page (Stores > Configuration).
In order to set the default values for the configuration fields, you need to create the following file in the module folder:
etc/config.xml
and add this code:
<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Store:etc/config.xsd">
<default>
<section_id>
<group_id>
<field_id>default_value</field_id>
</group_id>
</section_id>
</default>
</config>
In the previous article we explained how to configure and delimitate access rights for the Magento 2 admin panel users. In this article, you will learn how to create your own access rules (Role Resources).
You need to create ACL file (ACL - Access Control List) in your module folder:
etc/acl.xml
To find the Magento 2 configuration page navigate to Magento 2 Admin Panel > Stores > Configuration.
All tabs and forms on this page are customized using this file
etc/adminhtml/system.xml
To add a new table to the Magento 2 database, you need to create a file in the module folder:
app/code/<VendorName>/<ModuleName>/Setup/InstallSchema.php
add the following code to it:
<?php
namespace VendorName\ModuleName\Setup;
use Magento\Framework\Setup\InstallSchemaInterface;
use Magento\Framework\Setup\ModuleContextInterface;
use Magento\Framework\Setup\SchemaSetupInterface;
use Magento\Framework\DB\Adapter\AdapterInterface;
class InstallSchema implements InstallSchemaInterface
{
public function install(SchemaSetupInterface $setup, ModuleContextInterface $context)
{
$installer = $setup;
$installer->startSetup();
//new table script will be there
$installer->endSetup();
}
}
Since you already know how to create first controller in Magento 2 and to display the "Hello World" text on your own page, in this article we will show you how to display it in the new block.
1. Add a new PHP class block.
Create this file:
app/code/<VendorName>/<ModuleName>/Block/SomeName.php
and add the following code to it:
<?php
namespace VendorName\ModuleName\Block;
class SomeName extends \Magento\Framework\View\Element\Template
{
public function getWelcomeText()
{
return 'Hello World';
}
}
where,
SomeName is a random name in CamelCase format.
\Magento\Framework\View\Element\Template — a class from which you inherit your own block that interacts with the template.
getWelcomeText — a public method we created to return the text "Hello World". You can create a name for it yourself.