Magento 2: How to additonalClasses for Tab in form ui component?

Question

i try this code but it not working with tab in form ui component:

<item name="additionalClasses" xsi:type="array">
    <item name="my-custom-class" xsi:type="boolean">true</item>
</item>

Answer 1

Try this code to add additonalclasses for tab in form ui component.

More information in details, Visit, How to additonalClasses for Tab in Magento 2 UI component form

<fieldset name="address" sortOrder="30">
     <settings>
        <additionalClasses>
            <class name="custom-address">true</class>
        </additionalClasses>
    </settings>
</fieldset>

Hope this helps. Thanks.

Answer 2

Try using following example:

<?xml version="1.0" encoding="UTF-8"?>
<form xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Ui:etc/ui_configuration.xsd">
    <fieldset name="websites" sortOrder="30">
        <argument name="data" xsi:type="array">
            <item name="config" xsi:type="array">
                <item name="additionalClasses" xsi:type="string">admin__field-medium</item>
            </item>
        </argument>
    </fieldset>
</form>