How to Resolve the "Magento2 Product Grid Multiselect Component Override Showing Product Repeat on Next Page" Issue

Table of Contents

1. Introduction
2. Understanding the Issue
3. Identifying the Root Cause
4. Implementing the Solution
5. Conclusion

Introduction

Imagine this scenario: you are working with Magento 2 and have successfully overridden the admin product grid multiselect UI component to hide the 'Select All' option from the dropdown menu. Everything seems perfect until you notice a glitch. When you select 'Select All on this page' and navigate to another page, the last product from the previous page is inexplicably displayed on the next page again. This problem disrupts the product count and introduces inconsistencies in your admin grid.

If you are experiencing this, you are not alone. Many developers face similar issues when working with overrides in Magento 2. This blog post aims to guide you through the steps needed to identify the problem and provide robust solutions to resolve it. By the end of this post, you will have a clear understanding of how to navigate this issue effectively.

Understanding the Issue

Before diving into the solution, it is crucial to understand why this issue occurs. The Magento 2 framework employs various JavaScript components for rendering the admin grid. These components interact with local storage and server data to display products. When you override these components, unexpected behaviors such as product repetition can occur due to discrepancies in data handling between the client-side and the server-side.

Identifying the Root Cause

Initial Observations

• Product Count Mismatch: When products are selected on one page and navigation occurs, the last product from the previous page appears again on the subsequent page.
• Correct First Load: The products load correctly the first time but show incorrect data upon navigating back or forward.
• Local Storage Interference: The issue occurs because products are loaded from local storage when navigating through the pages.

Diagnosing the Issue

To diagnose this, you can add console log statements in your custom JavaScript files to trace the flow of data. This will help confirm if local storage is causing the repetitiveness of products. For instance:

console.log('Products loaded from local storage', localStorage.getItem('productGridData'));

You can also remove your custom JavaScript code to see if the issue persists. If the problem remains, it is an indication that the root cause lies in the interaction between your custom code and Magento's default behavior.

Implementing the Solution

Step 1: Correcting the JavaScript Logic

In your overridden JavaScript file Vendor/CatalogAdmin/view/adminhtml/web/js/grid/columns/multiselect-mixin.js, ensure that the logic for handling selected products does not rely exclusively on local storage. Implement a function to synchronize the selected products with the server data each time a page navigation occurs.

define([
    'jquery',
    'uiComponent',
    'Magento_Ui/js/grid/columns/multiselect',
    'ko'
], function ($, Component, multiselect, ko) {
    'use strict';

    return multiselect.extend({
        initialize: function () {
            this._super();
            var self = this;

            // Override method to correctly handle page navigation
            $(document).on('pageNavigation', function () {
                self.clearStorageAndReload();
            });

            return this;
        },

        clearStorageAndReload: function () {
            // Clear local storage
            localStorage.removeItem('productGridData');
            // Re-fetch the data from the server
            this._fetchDataFromServer();
        },

        _fetchDataFromServer: function () {
            // Logic to fetch and re-render data from server
        }
    });
});

Step 2: Updating the RequireJS Configuration

Ensure your requirejs-config.js file correctly maps your custom override to Magento's core components. This prevents Magento from loading default components instead of your custom ones.

var config = {
    config: {
        mixins: {
            'Magento_Ui/js/grid/columns/multiselect': {
                'Vendor_CatalogAdmin/js/grid/columns/multiselect-mixin': true
            }
        }
    }
};

Step 3: Testing the Implementation

After updating the JavaScript logic and RequireJS configuration, clear Magento's cache and redeploy the static content to ensure your changes take effect:

php bin/magento cache:clean
php bin/magento setup:static-content:deploy -f

Test the scenario again by selecting products and navigating between pages to confirm the issue is resolved.

Conclusion

Fixing the Magento 2 product grid multiselect issue that causes product repetition on navigation can be challenging. By diagnosing the root cause, updating JavaScript logic, and configuring RequireJS appropriately, you can overcome this problem effectively.

FAQs

1. Why does the product repetition issue occur in Magento 2?

The issue often happens due to discrepancies in data handling between local storage and server data when overriding JavaScript components.

2. How can I confirm local storage is causing the issue?

Use console log statements to trace data flow and confirm if local storage is responsible for the repetitive display of products.

3. What should I update in my RequireJS configuration?

Ensure that your custom JavaScript mixins are appropriately mapped to override Magento's core components.

4. Does clearing the Magento cache help?

Yes, clearing the cache and redeploying static content ensures that your changes take effect properly.

By following these steps and implementing the provided solution, you can resolve the product repetition issue and create a more reliable user experience in your Magento 2 admin panel.