System.xml throws an unexpected Error

[ShivaHaze]

EDIT: I got it fixed. Whoever is interested in the solution:
1) <tab>Neusta</tab> had to become <tab>neusta</tab>

2) <source_model>Neusta\StockTrafficLight\Model\Source\Align</source_model> simply didn't exist.

Hey :-)

I'm currently trying to learn Magento2 and started developing an extension, but sadly my system.xml throws some unexpected errors which I'm not sure how to handle.

Notice: Undefined index: id in /magento2/vendor/magento/module-config/Model/Config/Structure/Element/Iterator.php on line 59
#0 /magento2/vendor/magento/module-config/Model/Config/Structure/Element/Iterator.php(59): Magento\Framework\App\ErrorHandler->handler(8, 'Undefined index...', '/magento2/vendo...', 59, Array)
#1 /magento2/vendor/magento/module-config/Model/Config/Structure.php(85): Magento\Config\Model\Config\Structure\Element\Iterator->setElements(Array, 'default')
#2 /magento2/var/generation/Magento/Config/Model/Config/Structure/Interceptor.php(24): Magento\Config\Model\Config\Structure->getTabs()
#3 /magento2/vendor/magento/module-config/Model/Config/Structure.php(108): Magento\Config\Model\Config\Structure\Interceptor->getTabs()
#4 /magento2/var/generation/Magento/Config/Model/Config/Structure/Interceptor.php(50): Magento\Config\Model\Config\Structure->getFirstSection()
#5 /magento2/vendor/magento/module-config/Controller/Adminhtml/System/AbstractConfig.php(50): Magento\Config\Model\Config\Structure\Interceptor->getFirstSection()
#6 [internal function]: Magento\Config\Controller\Adminhtml\System\AbstractConfig->dispatch(Object(Magento\Framework\App\Request\Http))
#7 /magento2/vendor/magento/framework/Interception/Interceptor.php(74): call_user_func_array(Array, Array)
#8 /magento2/vendor/magento/framework/Interception/Chain/Chain.php(70): Magento\Config\Controller\Adminhtml\System\Config\Index\Interceptor->___callParent('dispatch', Array)
#9 /magento2/vendor/magento/framework/Interception/Chain/Chain.php(63): Magento\Framework\Interception\Chain\Chain->invokeNext('Magento\\Config\\...', 'dispatch', Object(Magento\Config\Controller\Adminhtml\System\Config\Index\Interceptor), Array, 'adminAuthentica...')
#10 /magento2/vendor/magento/module-backend/App/Action/Plugin/Authentication.php(143): Magento\Framework\Interception\Chain\Chain->Magento\Framework\Interception\Chain\{closure}(Object(Magento\Framework\App\Request\Http))
#11 [internal function]: Magento\Backend\App\Action\Plugin\Authentication->aroundDispatch(Object(Magento\Config\Controller\Adminhtml\System\Config\Index\Interceptor), Object(Closure), Object(Magento\Framework\App\Request\Http))
#12 /magento2/vendor/magento/framework/Interception/Chain/Chain.php(67): call_user_func_array(Array, Array)
#13 /magento2/vendor/magento/framework/Interception/Chain/Chain.php(63): Magento\Framework\Interception\Chain\Chain->invokeNext('Magento\\Config\\...', 'dispatch', Object(Magento\Config\Controller\Adminhtml\System\Config\Index\Interceptor), Array, 'designLoader')
#14 /magento2/vendor/magento/framework/App/Action/Plugin/Design.php(39): Magento\Framework\Interception\Chain\Chain->Magento\Framework\Interception\Chain\{closure}(Object(Magento\Framework\App\Request\Http))
#15 [internal function]: Magento\Framework\App\Action\Plugin\Design->aroundDispatch(Object(Magento\Config\Controller\Adminhtml\System\Config\Index\Interceptor), Object(Closure), Object(Magento\Framework\App\Request\Http))
#16 /magento2/vendor/magento/framework/Interception/Chain/Chain.php(67): call_user_func_array(Array, Array)
#17 /magento2/vendor/magento/framework/Interception/Interceptor.php(136): Magento\Framework\Interception\Chain\Chain->invokeNext('Magento\\Config\\...', 'dispatch', Object(Magento\Config\Controller\Adminhtml\System\Config\Index\Interceptor), Array, 'adminMassaction...')
#18 /magento2/vendor/magento/module-backend/App/Action/Plugin/MassactionKey.php(33): Magento\Config\Controller\Adminhtml\System\Config\Index\Interceptor->Magento\Framework\Interception\{closure}(Object(Magento\Framework\App\Request\Http))
#19 [internal function]: Magento\Backend\App\Action\Plugin\MassactionKey->aroundDispatch(Object(Magento\Config\Controller\Adminhtml\System\Config\Index\Interceptor), Object(Closure), Object(Magento\Framework\App\Request\Http))
#20 /magento2/vendor/magento/framework/Interception/Interceptor.php(140): call_user_func_array(Array, Array)
#21 /magento2/var/generation/Magento/Config/Controller/Adminhtml/System/Config/Index/Interceptor.php(40): Magento\Config\Controller\Adminhtml\System\Config\Index\Interceptor->___callPlugins('dispatch', Array, Array)
#22 /magento2/vendor/magento/framework/App/FrontController.php(55): Magento\Config\Controller\Adminhtml\System\Config\Index\Interceptor->dispatch(Object(Magento\Framework\App\Request\Http))
#23 [internal function]: Magento\Framework\App\FrontController->dispatch(Object(Magento\Framework\App\Request\Http))
#24 /magento2/vendor/magento/framework/Interception/Interceptor.php(74): call_user_func_array(Array, Array)
#25 /magento2/vendor/magento/framework/Interception/Chain/Chain.php(70): Magento\Framework\App\FrontController\Interceptor->___callParent('dispatch', Array)
#26 /magento2/vendor/magento/framework/Interception/Interceptor.php(136): Magento\Framework\Interception\Chain\Chain->invokeNext('Magento\\Framewo...', 'dispatch', Object(Magento\Framework\App\FrontController\Interceptor), Array, 'install')
#27 /magento2/vendor/magento/framework/Module/Plugin/DbStatusValidator.php(69): Magento\Framework\App\FrontController\Interceptor->Magento\Framework\Interception\{closure}(Object(Magento\Framework\App\Request\Http))
#28 [internal function]: Magento\Framework\Module\Plugin\DbStatusValidator->aroundDispatch(Object(Magento\Framework\App\FrontController\Interceptor), Object(Closure), Object(Magento\Framework\App\Request\Http))
#29 /magento2/vendor/magento/framework/Interception/Interceptor.php(140): call_user_func_array(Array, Array)
#30 /magento2/var/generation/Magento/Framework/App/FrontController/Interceptor.php(26): Magento\Framework\App\FrontController\Interceptor->___callPlugins('dispatch', Array, Array)
#31 /magento2/vendor/magento/framework/App/Http.php(115): Magento\Framework\App\FrontController\Interceptor->dispatch(Object(Magento\Framework\App\Request\Http))
#32 /magento2/vendor/magento/framework/App/Bootstrap.php(258): Magento\Framework\App\Http->launch()
#33 /magento2/index.php(40): Magento\Framework\App\Bootstrap->run(Object(Magento\Framework\App\Http))
#34 {main}

My system.xml looks like this:

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../../Magento/Config/etc/system_file.xsd">
    <system>
        <tab id="neusta" translate="label" sortOrder="10">
            <label>Neusta</label>
        </tab>
        <section id="neusta_stocktraffclight" translate="label" type="text" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1">
            <label>Neusta_StockTrafficLight</label>
            <tab>Neusta</tab>
            <resource>Neusta_StockTrafficLight::neusta_stocktraffclight</resource>
            <group id="general" translate="label" type="text" sortOrder="10" showInDefault="1" showInWebsite="0" showInStore="0">
                <label>General</label>
                <field id="enable" translate="label comment" type="select" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1">
                    <label>Enable Stock Traffic Light</label>
                    <source_model>Magento\Config\Model\Config\Source\Yesno</source_model>
                    <comment>
                        Enable 'Stock Traffic Lights'.
                    </comment>
                </field>
                <field id="block_label" translate="label" type="text" sortOrder="20" showInDefault="1" showInWebsite="1" showInStore="1">
                    <label>Block Label</label>
                </field>
                <field id="text_align" translate="label" type="select" sortOrder="30" showInDefault="1" showInWebsite="1" showInStore="1">
                    <label>Text Align</label>
                    <source_model>Neusta\StockTrafficLight\Model\Source\Align</source_model>
                </field>
            </group>
        </section>
    </system>
</config>

Can anybody give me a hint what's wrong?

Cheerz!

[Tahir Yasin]

Did you manage to fix it? I am having same issue.

Please help.

[Bharat Desai]

class Align implements \Magento\Framework\Option\ArrayInterface
{
   public function toOptionArray()
    {
        return [
                         ['value' => -1, 'label' => __('None')],
                          ['value' => 0, 'label' => __('0%')],
         ];
    }
}

Did you over ride the Arrayinterface and toOptinArray in your source model file Align.

[VimirLab]

Remove Tab id.

like <tab>netus</tab>

[ivagarfitt3933]

Your tab id is:

<tab id="neusta"

And you put:

<tab>Neusta</tab>

Correct way is to be exactly the same like id name so:

<tab>neusta</tab>

Not a capital letter.

[verma_mallika]

Hi @ShivaHaze 

Replace below code in your system.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../../Magento/Config/etc/system_file.xsd">
    <system>
        <tab id="neusta" translate="label" sortOrder="10">
            <label>Neusta</label>
        </tab>
        <section id="neusta_stocktraffclight" translate="label" type="text" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1">
            <label>Neusta StockTrafficLight</label>
            <tab>neusta</tab>
            <resource>Neusta_StockTrafficLight::neusta_stocktraffclight</resource>
            <group id="general" translate="label" type="text" sortOrder="10" showInDefault="1" showInWebsite="0" showInStore="0">
                <label>General</label>
             <field id="enable" translate="label comment" type="select" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1">
                    <label>Enable Stock Traffic Light</label>
                    <source_model>Magento\Config\Model\Config\Source\Yesno</source_model>
                    <comment>
                        Enable 'Stock Traffic Lights'.
                    </comment>
                </field>
                <field id="block_label" translate="label" type="text" sortOrder="20" showInDefault="1" showInWebsite="1" showInStore="1">
                    <label>Block Label</label>
                </field>
                <field id="text_align" translate="label" type="select" sortOrder="30" showInDefault="1" showInWebsite="1" showInStore="1">
                    <label>Text Align</label>
                    <source_model>Neusta\StockTrafficLight\Model\Source\Align</source_model>
                </field>  
            </group>
        </section>
    </system>
</config>

I think you had already created Neusta\StockTrafficLight\Model\Source\Align file right?

The error in your code was that, you need to use tab id inside section tab. By mistake I think you had used tab id by capital letter.

Let me know if it worked.