The negative syntax for a backend config field <depends> condition

dmitry_fedyuk · December 21, 2015, 9:37am

The core never uses this possibility, but there is a (single) example in a unit test:

magento/magento2/blob/2.0.0/app/code/Magento/Config/Test/Unit/Model/Config/_files/valid_system.xml#L23-L25


<depends>
    <field id="depends_field"  separator="," negative="1">2</field>
</depends>

Schema:

github.com

magento/magento2/blob/2.0.0/app/code/Magento/Config/etc/system_file.xsd#L377


                <xs:annotation>
                    <xs:documentation>
                        Field resource. Recursive complex type. Define element is influence on current field
                    </xs:documentation>
                </xs:annotation>


                <xs:simpleContent>
                    <xs:extension base="xs:string">
                        <xs:attribute name="id" type="typeElementPath" use="required" />
                        <xs:attribute name="separator" type='xs:string' use='optional' />
                        <xs:attribute name="negative" type='xs:int' use='optional' />
                    </xs:extension>
                </xs:simpleContent>
            </xs:complexType>
        </xs:element>
    </xs:sequence>
</xs:complexType>


<xs:unique name="uniqueDependsFieldId">
    <xs:annotation>
        <xs:documentation>

How it works:

Step 1

github.com

magento/magento2/blob/2.0.0/app/code/Magento/Config/Model/Config/Structure/Element/Dependency/Field.php#L51


    }
    $fieldId = $fieldPrefix . (isset(
        $fieldData['dependPath']
    ) && is_array(
        $fieldData['dependPath']
    ) ? array_pop(
        $fieldData['dependPath']
    ) : '');
    $fieldData['dependPath'][] = $fieldId;
    $this->_id = implode('_', $fieldData['dependPath']);
    $this->_isNegative = isset($fieldData['negative']) && $fieldData['negative'];
}


/**
 * Check whether the value satisfy dependency
 *
 * @param string $value
 * @return bool
 */
public function isValueSatisfy($value)
{

Step 2

github.com

magento/magento2/blob/2.0.0/app/code/Magento/Config/Model/Config/Structure/Element/Dependency/Field.php#L85-L93


/**
 * Get negative indication of dependency
 *
 * @return bool
 */
public function isNegative()
{
    return $this->_isNegative;
}

Step 3

github.com

magento/magento2/blob/2.0.0/app/code/Magento/Backend/Block/Widget/Form/Element/Dependence.php#L145


 * @return string
 */
protected function _getDependsJson()
{
    $result = [];
    foreach ($this->_depends as $to => $row) {
        foreach ($row as $from => $field) {
            /** @var $field \Magento\Config\Model\Config\Structure\Element\Dependency\Field */
            $result[$this->_fields[$to]][$this->_fields[$from]] = [
                'values' => $field->getValues(),
                'negative' => $field->isNegative(),
            ];
        }
    }
    return $this->_jsonEncoder->encode($result);
}
}

Step 4

github.com

magento/magento2/blob/2.0.0/lib/web/mage/adminhtml/form.js#L367-L370


var isNegative = valuesFrom[idFrom]['negative'];
if (!from || isInArray && isNegative || !isInArray && !isNegative) {
    shouldShowUp = false;
}

dmitry_fedyuk · December 26, 2015, 3:23pm

mage2pro/facebook-login/blob/1.1.15/etc/adminhtml/system.xml?ts=4#L100-L115


						<field
							id='label'
							translate='label'
							type='text'
							sortOrder='3'
							showInDefault='1'
							showInWebsite='1'
							showInStore='1'
						>
							<label>Label</label>
							<depends>
								<field id='enable'>1</field>
								<field id='type' negative='1'>button-native</field>
							</depends>
							<validate>required-entry</validate>
						</field>