Magento 2: Add new button on Category Edit Page in Admin Panel

For this example we will assume you have a custom module. Let's call it Namespace_Module.

Now, create files as below:

Namespace_Module\view\adminhtml\ui_component\category_form.xml

	<?xml version="1.0" encoding="UTF-8"?>
	<!--
	/**
	* @author Reena Parekh <reena1.parekh@gmail.com>
	*/
	-->
	<form xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Ui:etc/ui_configuration.xsd">
	<argument name="data" xsi:type="array">
	<item name="buttons" xsi:type="array">
	<item name="button-unique-identifier-here" xsi:type="string">
	Namespace\Module\Block\Adminhtml\Category\Edit\Button\AssignButton
	</item>
	</item>
	</argument>
	</form>

view raw category_form.xml hosted with ❤ by GitHub

Namespace_Module\Block\Adminhtml\Category\Edit\Button\AssignButton.php

	<?php
	<!--
	/**
	* @author Reena Parekh <reena1.parekh@gmail.com>
	*/
	-->
	namespace Namespace\Module\Block\Adminhtml\Category\Edit\Button;
	use Magento\Catalog\Block\Adminhtml\Category\AbstractCategory;
	use Magento\Framework\View\Element\UiComponent\Control\ButtonProviderInterface;
	class AssignButton extends AbstractCategory implements ButtonProviderInterface
	{
	/**
	* Assign button
	*
	* @return array
	*/
	public function getButtonData()
	{
	$category = $this->getCategory();
	$message = __('Are you sure you want to submit the data ?');
	if (!$category->isReadonly() && $this->hasStoreRootCategory()) {
	return [
	'label' => __('Assign'),
	'class' => 'assign primary',
	'on_click' => "confirmSetLocation('{$message}', '{$this->getCustomUrl()}')",
	'sort_order' => 30,
	];
	}
	return [];
	}
	/**
	* URL getter
	*
	* @return string
	*/
	public function getCustomUrl()
	{
	return $this->getUrl('mymodule/category/assign', ['category_id' => $this->getCategory()->getId()]);
	}
	}

view raw AssignButton.php hosted with ❤ by GitHub

Namespace_Module\Controller\Adminhtml\Category\Assign.php

	<?php
	/**
	* @author Reena Parekh <reena1.parekh@gmail.com>
	*/
	namespace Namespace\Module\Controller\Adminhtml\Category;
	/**
	* Class Assign
	*/
	class Assign extends \Magento\Catalog\Controller\Adminhtml\Category
	{
	/**
	* @return \Magento\Framework\App\ResponseInterface|\Magento\Framework\Controller\ResultInterface|void
	* @throws \Magento\Framework\Exception\LocalizedException
	*/
	public function execute()
	{
	$resultRedirect = $this->resultRedirectFactory->create();
	if ($categoryId = $this->getRequest()->getParam('category_id')) {
	//Add code related to whatever you want to do on button click here.
	$this->messageManager->addSuccess(__('Operation performed successfully.'));
	$resultRedirect->setPath('catalog/category/edit', ['id' => $categoryId, '_current' => true]);
	}
	return $resultRedirect;
	}
	}

view raw Assign.php hosted with ❤ by GitHub

Voila !! That's it. Now, clear all caches and check the category page in admin panel. There will be a new button called "Assign".