Magento 2 : Problem while adding custom button order view page?

Question

di.xml

<?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="Magento\Backend\Block\Widget\Context">
        <plugin name="add_custom_button_sales_veiw" type="MyModule\RK\Plugin\Widget\Context" sortOrder="1"/>
    </type>
</config>

Context.php

<?php
namespace MyModule\RK\Plugin\Widget;

class Context
{
    public function afterGetButtonList(
        \Magento\Backend\Block\Widget\Context $subject,
         $buttonList
    )
    {
        if($subject->getRequest()->getFullActionName() == 'sales_order_view'){
            $buttonList->add(
                'custom_button',
                [
                    'label' => 'test',
                    'onclick' => "setLocation('window.location.href')",
                    'class' => 'ship'
                ]
            );
        }

        return $buttonList;
    }
}

Review button is not displaying on order view page what i am doing wrong ??

Answer 1

Change your di.xml [Vendor/Module/etc/adminhtml/di.xml]:

<?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="Magento\Backend\Block\Widget\Context">
        <plugin name="add_custom_button_sales_veiw" type="Vendor\Module\Plugin\Widget\Context" sortOrder="1"/>
    </type>
</config>

Create plugin [Vendor/Module/Plugin/Widget/Context.php]

namespace Vedor\Module\Plugin\Widget;


class Context
{
    public function afterGetButtonList(
        \Magento\Backend\Block\Widget\Context $subject,
        $buttonList
    )
    {
        if($subject->getRequest()->getFullActionName() == 'sales_order_view'){
            $buttonList->add(
                'custom_button',
                [
                    'label' => __('Custom Button'),
                    'onclick' => "setLocation('window.location.href')",
                    'class' => 'ship'
                ]
            );
        }

        return $buttonList;
    }
}

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