magento how add dynamic url path in system.xml - magento

Question

I am working on payment gateway. but i have problem i did google research but couldn't find any solution i hope i'll get solution here so i am posting here
following my system.xml code block
<title translate="label">
<label>Title</label>
<comment><![CDATA[<img src="/media/billmate/images/billmate_bank_s.png" />]]></comment>
<frontend_type>text</frontend_type>
<sort_order>3</sort_order>
<show_in_default>1</show_in_default>
<show_in_website>1</show_in_website>
<show_in_store>1</show_in_store>
</title>
in this block problem is in comment tag right now here i put static link /media/billmate/images/billmate_bank_s.png please anybody suggess me how to make it dynamic

Answer 1

An element from system.xml can have a dynamic comment. The comment can be rendered through a model.
You need to declare the comment field like this:
<comment>
<model>module/adminhtml_comment</model>
</comment>
Now you need to create the model with alias module/adminhtml_comment:
<?php
class Namespace_Module_Model_Adminhtml_Comment{
public function getCommentText(){ //this method must exits. It returns the text for the comment
return "Some text here";
}
}
like following
<title translate="label">
<label>Title</label>
<comment>
<model>module/adminhtml_comment</model>
</comment>
<frontend_type>text</frontend_type>
<sort_order>3</sort_order>
<show_in_default>1</show_in_default>
<show_in_website>1</show_in_website>
<show_in_store>1</show_in_store>
</title>
return value from the getCommentText method

Answer 2

Add into system.xml file
<field id="row_payment_us_free" translate="label" type="select" sortOrder="5" showInDefault="1" showInStore="1" showInWebsite="1" canRestore="1">
<label>Payment US Free</label>
<source_model>Magento\Config\Model\Config\Source\Yesno</source_model>
<comment><model>VendoreName\ModuleName\Model\SystemConfigComment</model></comment>
</field>
app/code/VendoreName/ModuleName/Model
SystemConfigComment.php
<?php
namespace VendoreName\ModuleName\Model;
use Magento\Framework\UrlInterface;
class SystemConfigComment implements \Magento\Config\Model\Config\CommentInterface
{
protected $urlInterface;
public function __construct(
UrlInterface $urlInterface
) {
$this->urlInterface = $urlInterface;
}
public function getCommentText($elementValue)
{
$url = $this->urlInterface->getUrl('adminhtml/system_config/edit/section/payment');
return 'Require to enable Zero Subtotal Checkoutpayment method for Zero Subtotal order.';
}
}