nodwell.net

Trying to remove a block from a layout and it won’t go away? A trick to figure out where you are working is to use $block->getNameInLayout() and that should tell you what block you need to remove.

Did you create a module, does it load after or before a core module that might be putting your block back in? Did you set the core module as a dependency in both composer.json and module.xml in your module? If not, add that in, and setup:upgrade module:disable your module and setup:upgrade module:enable your module to force the dependency order to get reset.

Limitations

Plugins can not be used on following:

• Final methods
• Final classes
• Non-public methods
• Class methods (such as static methods)
• __construct
• Virtual types
• Objects that are instantiated before Magento\Framework\Interception is bootstrapped

public function match (\Magento\Framework\App\RequestInterface $request)
{
    if (strpos($request->getPathInfo(), 'test') === false) return;
    $request->setModuleName(‘MyCompany_MyModule’)
       ->setControllerName('test')->setActionName('test');

    return $this->actionFactory->create(
        \Magento\Framework\App\Action\Forward::class, ['request' => $request]
    );
}

https://magento.stackexchange.com/questions/135532/magento-2-ce-front-controller-reached-100-router-match-iterations-issue

All the different type of form fields available in magento are located in folder lib\Varien\Data\Form\Element

Here is how to add a text field to an admin form, with a list of all the options

$fieldset->addField('title', 'text', array(
          'label'     => Mage::helper('form')->__('Title3'),
          'class'     => 'required-entry',
          'required'  => true,
          'name'      => 'title',
		  'onclick' => "alert('on click');",
		  'onchange' => "alert('on change');",
		  'style'   => "border:10px",
		  'value'  => 'hello !!',
		  'disabled' => false,
		  'readonly' => true,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('time', 'time', array(
          'label'     => Mage::helper('form')->__('Time'),
          'class'     => 'required-entry',
          'required'  => true,
          'name'      => 'title',
		  'onclick' => "",
		  'onchange' => "",
		  'value'  => '12,04,15',
		  'disabled' => false,
		  'readonly' => false,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('textarea', 'textarea', array(
          'label'     => Mage::helper('form')->__('TextArea'),
          'class'     => 'required-entry',
          'required'  => true,
          'name'      => 'title',
		  'onclick' => "",
		  'onchange' => "",
		  'value'  => '<b><b/>',
		  'disabled' => false,
		  'readonly' => false,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('submit', 'submit', array(
          'label'     => Mage::helper('form')->__('Submit'),
          'required'  => true,
		  'value'  => 'Submit',
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('select', 'select', array(
          'label'     => Mage::helper('form')->__('Select'),
          'class'     => 'required-entry',
          'required'  => true,
          'name'      => 'title',
		  'onclick' => "",
		  'onchange' => "",
		  'value'  => '1',
		  'values' => array('-1'=>'Please Select..','1' => 'Option1','2' => 'Option2', '3' => 'Option3'),
		  'disabled' => false,
		  'readonly' => false,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

Here is another version of the drop down

$fieldset->addField('select2', 'select', array(
          'label'     => Mage::helper('form')->__('Select Type2'),
          'class'     => 'required-entry',
          'required'  => true,
          'name'      => 'title',
		  'onclick' => "",
		  'onchange' => "",
		  'value'  => '4',
		  'values' => array(
		  						'-1'=>'Please Select..',
		  						'1' => array( 
												'value'=> array(array('value'=>'2' , 'label' => 'Option2') , array('value'=>'3' , 'label' =>'Option3') ),
												'label' => 'Size'	 
										   ),
								'2' => array( 
												'value'=> array(array('value'=>'4' , 'label' => 'Option4') , array('value'=>'5' , 'label' =>'Option5') ),
												'label' => 'Color'	 
										   ),										   
							     
						   ),
		  'disabled' => false,
		  'readonly' => false,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('radio', 'radio', array(
          'label'     => Mage::helper('form')->__('Radio'),
          'name'      => 'title',
		  'onclick' => "",
		  'onchange' => "",
		  'value'  => '1',
		  'disabled' => false,
		  'readonly' => false,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('radio2', 'radios', array(
          'label'     => Mage::helper('form')->__('Radios'),
          'name'      => 'title',
		  'onclick' => "",
		  'onchange' => "",
		  'value'  => '2',
		  'values' => array(
		  					array('value'=>'1','label'=>'Radio1'),
		  					array('value'=>'2','label'=>'Radio2'),
		  					array('value'=>'3','label'=>'Radio3'),
		  			   ),
		  'disabled' => false,
		  'readonly' => false,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('password', 'password', array(
          'label'     => Mage::helper('form')->__('Password'),
          'class'     => 'required-entry',
          'required'  => true,
          'name'      => 'title',
		  'onclick' => "",
		  'onchange' => "",
		  'style'   => "",
		  'value'  => 'hello !!',
		  'disabled' => false,
		  'readonly' => false,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('obscure', 'obscure', array(
          'label'     => Mage::helper('form')->__('Obscure'),
          'class'     => 'required-entry',
          'required'  => true,
          'name'      => 'obscure',
		  'onclick' => "",
		  'onchange' => "",
		  'style'   => "",
		  'value'  => '123456789',
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('note', 'note', array(
          'text'     => Mage::helper('form')->__('Text Text'),
		));

$fieldset->addField('multiselect2', 'multiselect', array(
          'label'     => Mage::helper('form')->__('Select Type2'),
          'class'     => 'required-entry',
          'required'  => true,
          'name'      => 'title',
		  'onclick' => "return false;",
		  'onchange' => "return false;",
		  'value'  => '4',
		  'values' => array(
		  						'-1'=> array( 'label' => 'Please Select..', 'value' => '-1'),
		  						'1' => array( 
												'value'=> array(array('value'=>'2' , 'label' => 'Option2') , array('value'=>'3' , 'label' =>'Option3') ),
												'label' => 'Size'	 
										   ),
								'2' => array( 
												'value'=> array(array('value'=>'4' , 'label' => 'Option4') , array('value'=>'5' , 'label' =>'Option5') ),
												'label' => 'Color'	 
										   ),										   
							     
						   ),
		  'disabled' => false,
		  'readonly' => false,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));
		

$fieldset->addField('multiline', 'multiline', array(
          'label'     => Mage::helper('form')->__('Multi Line'),
          'class'     => 'required-entry',
          'required'  => true,
          'name'      => 'title',
		  'onclick' => "",
		  'onchange' => "",
		  'style'   => "border:10px",
		  'value'  => 'hello !!',
		  'disabled' => false,
		  'readonly' => true,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('link', 'link', array(
          'label'     => Mage::helper('form')->__('Link'),
		  'style'   => "",
		  'href' => 'www.excellencemagentoblog.com',
		  'value'  => 'Magento Blog',
		  'after_element_html' => ''
		));

$fieldset->addField('label', 'label', array(
          'value'     => Mage::helper('form')->__('Label Text'),
		));

$fieldset->addField('image', 'image', array(
          'value'     => 'http://www.excellencemagentoblog.com/wp-content/themes/excelltheme/images/logo.png',
		));

$fieldset->addField('file', 'file', array(
          'label'     => Mage::helper('form')->__('Upload'),
		  'value'  => 'Uplaod',
		  'disabled' => false,
		  'readonly' => true,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('date', 'date', array(
          'label'     => Mage::helper('form')->__('Date'),
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1,
		  'image' => $this->getSkinUrl('images/grid-cal.gif'),
	      'format' => Mage::app()->getLocale()->getDateFormat(Mage_Core_Model_Locale::FORMAT_TYPE_SHORT) 
		));

$fieldset->addField('checkbox', 'checkbox', array(
          'label'     => Mage::helper('form')->__('Checkbox'),
          'name'      => 'Checkbox',
		  'checked' => false,
		  'onclick' => "",
		  'onchange' => "",
		  'value'  => '1',
		  'disabled' => false,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

$fieldset->addField('checkboxes', 'checkboxes', array(
          'label'     => Mage::helper('form')->__('Checkboxs'),
          'name'      => 'Checkbox',
		  'values' => array(
		  					array('value'=>'1','label'=>'Checkbox1'),
		  					array('value'=>'2','label'=>'Checkbox2'),
		  					array('value'=>'3','label'=>'Checkbox3'),
		  			   ),
		  'onclick' => "",
		  'onchange' => "",
		  'value'  => '1',
		  'disabled' => false,
		  'after_element_html' => '<small>Comments</small>',
		  'tabindex' => 1
		));

In an effort to simplify the Magento installation and upgrade process, 2.3 introduces declarative schema.

With the new declarative schema approach allows,  developers are no longer forced to write scripts for each new version of a module. Using declarative schema, developers declare the final desired state of the database, and the system adjusts to it automatically, without performing redundant operations. In addition, this approach allows data to be easily deleted when a module is uninstalled.

There are two parts to using declarative schema: the db_schema.xml file and the bin/magento command to register it.

Once you use declarative schema in a module, you cannot use setup/upgrade scripts again. In the future, upgrade scripts will be phased out in favor of declarative schema.

The following example, extracted from the Catalog/etc/db_schema.xml file, defines the catalog_product_entity_datetime table:

<table name="catalog_product_entity_datetime" resource="default" engine="innodb"
           comment="Catalog Product Datetime Attribute Backend Table">
        <column xsi:type="int" name="value_id" padding="11" unsigned="false" nullable="false" identity="true" comment="Value ID"/>
        <column xsi:type="smallint" name="attribute_id" padding="5" unsigned="true" nullable="false" identity="false"default="0" comment="Attribute ID"/>
        <column xsi:type="smallint" name="store_id" padding="5" unsigned="true" nullable="false" identity="false" default="0" comment="Store ID"/>
        <column xsi:type="int" name="entity_id" padding="10" unsigned="true" nullable="false" identity="false" default="0"/>
        <column xsi:type="datetime" name="value" on_update="false" nullable="true" comment="Value"/>
        <constraint xsi:type="primary" name="PRIMARY">
            <column name="value_id"/>
        </constraint>
</table>

https://magento-devdocs.github.io/devdocs-for-tests/guides/v2.3/extension-dev-guide/declarative-schema/db-schema.html