Is it possible to add a system.xml
file for module configurations in Magento 2? If so, how?
Yes, In magento 2 it's possible to create system configuration file same as Magento 1.x. But it will need to create some other files.
Need to use following file to create it.
1) app/code/Vendor/Helloworld/etc/adminhtml/system.xml
2) app/code/Vendor/Helloworld/etc/acl.xml
This 2 files are important to create system configuration.
In system.xml
file
Adding the common content
<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../Config/etc/system_file.xsd">
<system>
<!-- Add new Tab -->
<tab id="vendor" translate="label" sortOrder="300">
<label>Vendor Extension</label>
</tab>
<section id="helloworld" translate="label" type="text" sortOrder="140" showInDefault="1" showInWebsite="1" showInStore="1">
<label>Helloworld</label>
<tab>vendor</tab>
<!-- resource tag name which we have to defined in the acl.xml -->
<resource>Vendor_Helloworld::config_helloworld</resource>
<group id="general" translate="label" type="text" sortOrder="1" showInDefault="1" showInWebsite="1" showInStore="1">
<label>General Options</label>
<field id="active" translate="label" type="select" sortOrder="1" showInDefault="1" showInWebsite="1" showInStore="1">
<label>Enabled</label>
<source_model>Magento\Config\Model\Config\Source\Yesno</source_model>
</field>
</group>
</section>
</system>
</config>
In acl.xml
file
In the file need to write the below content
<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../../../lib/internal/Magento/Framework/Acl/etc/acl.xsd">
<acl>
<resources>
<resource id="Magento_Backend::admin">
<resource id="Magento_Backend::stores">
<resource id="Magento_Backend::stores_settings">
<resource id="Magento_Config::config">
<!-- this resource id we can use in system.xml for section -->
<resource id="Vendor_Helloworld::config_helloworld" title="Helloworld Section" sortOrder="80" />
</resource>
</resource>
</resource>
</resource>
</resources>
</acl>
</config>
After that, Clear the magento cache & logout from admin side. Then Login at admin side. In store > Configuration you can see the tab “Vendor Extension”. When you click on this you can see the detail of this.