Magento 2.0.x - Insert block in to the product page

Question

After about a week reading through the Magento 2 Docs - layout instructions, and some other stack exchange Q's and A's, I still having a hard time to figure out how to insert a custom block in to the specific location of the product page. What I have so far, in to the top of this page: /app/design/frontend/<Vendor>/<theme>/Magento_Catalog/templates/product/view/details.phtml

I have inserted this line of code:

echo $this->getLayout()->createBlock('Magento\Cms\Block\Block')->setBlockId('block_identifier')->toHtml();

In the product "Custom Lyout Update", i have inserted this XML

<referenceContainer name="block_identifier" >
 <block class="Magento\Framework\View\Element\Template" name="test_file" template="Magento_Theme::html/test.phtml" />
</referenceContainer>

The only time I can see contents of my test.php file is when I change referenceContainer name to predefined blocks as "content" or "product.info".

Links that I found useful:
Magento2- Display Static Block in Phtml file & CMS page
Magento 2 - How to call a custom phtml file in another phtml file, xml layout, static block and cms page?
How to show the static blocks in Magento 2?
Magento 2 tutorial – How to use the new front-end templating system

My current temp fix
I insert test.phtml file to a specific product this way.

<referenceContainer name="main" >
 <container name="product.info.desc" htmlTag="div" htmlId="product-info-desc-id" htmlClass="product-info-class" >
 <block class="Magento\Framework\View\Element\Template" name="test_file" template="Magento_Theme::html/test.phtml" />
 </container>
</referenceContainer>
<move element="product.info.desc" destination="content" after="product.info.media" />

Any help is greatly appreciated. Thank you.

• Bojjaiah: do you want insert your custom block in product view page in frontend or?
• crashtestxxx: Yes, I have to add more custom content to the specific product pages. Each product, if required, might have it's own unique and static content added. So, I created phtml page, product_id_whatever.phtml, and I need to insert it as block and position it before description/review tabs.

Answer 1

(1) first create a new module with a custom eav for your product content (this is just the InstallData.php content):

<?php namespace <vendor>\<module_name>\Setup;
use Magento\Eav\Setup\EavSetup;
use Magento\Eav\Setup\EavSetupFactory;
use Magento\Framework\Setup\InstallDataInterface;
use Magento\Framework\Setup\ModuleContextInterface;
use Magento\Framework\Setup\ModuleDataSetupInterface;
/**
 * @codeCoverageIgnore
 */
class InstallData implements InstallDataInterface
{
 /**
 * EAV setup factory
 *
 * @var EavSetupFactory
 */
 private $eavSetupFactory;
 /**
 * Init
 *
 * @param EavSetupFactory $eavSetupFactory
 */
 public function __construct(EavSetupFactory $eavSetupFactory)
 {
 $this->eavSetupFactory = $eavSetupFactory;
 /* assign object to class global variable for use in other class methods */
 }
 /**
 * {@inheritdoc}
 * @SuppressWarnings(PHPMD.ExcessiveMethodLength)
 */
 public function install(ModuleDataSetupInterface $setup, ModuleContextInterface $context)
 {
 $setup->startSetup();
 /** @var EavSetup $eavSetup */
 $eavSetup = $this->eavSetupFactory->create(['setup' => $setup]);
 /**
 * Add attributes to the eav/attribute
 */
 $eavSetup->addAttribute(
 \Magento\Catalog\Model\Product::ENTITY,
 'my_attribute',
 [
 'type' => 'text',
 'backend' => '',
 'frontend' => '',
 'label' => 'my custom content',
 'input' => 'textarea',
 'class' => '',
 'source' => '',
 'global' => 1,
 'visible' => true,
 'required' => false,
 'user_defined' => true,
 'default' => 0,
 'searchable' => false,
 'filterable' => false,
 'comparable' => false,
 'visible_on_front' => false,
 'used_in_product_listing' => true,
 'wysiwyg_enabled' => true, // if you want a wysiwyg editor
 'unique' => false,
 'apply_to' => 'simple,configurable,virtual,bundle,downloadable,grouped',
 'group' => 'General'
 ]
 );
 $setup->endSetup();
 }
}

(2) in the module extend catalog_product_view.xml to insert your attribute: [I added mine as a new product tab]

<referenceBlock name="product.info.details">
 <block class="Magento\Catalog\Block\Product\View\Description" name="{SOME_NAME}" template="product/view/attribute.phtml" group="detailed_info">
 <arguments>
 <argument name="at_call" xsi:type="string">getMyAttribute</argument>
 <argument name="at_code" xsi:type="string">my_attribute</argument>
 <argument name="css_class" xsi:type="string">{some class if you like}</argument>
 <argument name="at_label" xsi:type="string">none</argument>
 <argument name="title" translate="true" xsi:type="string">My tab label</argument>
 </arguments>
 </block>
</referenceBlock>

(3) now you can go to your magento admin and insert custom content (even html) into the attribute content like for every other attribute

Answer 2

In app\code\Namespace\Modulename\view\frontend\layout\catalog_product_view.xml add like below code. You can use your required referenceContainer

<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
 <body>
 <referenceContainer name="alert.urls">
 <block class="Namespace\Modulename\Block\Catalog\Product\View\Module" name="textblock" as="textblock" after="-" template="catalog/product/view/textblock.phtml" />
 </referenceContainer>
 </body>
</page>