In order to display data of our Field Type from templates, we need to create and register a template for it. You can find documentation about FieldType templates, as well as on importing settings from a bundle.
In a couple words, such a template must:
extend
EzPublishCoreBundle::content_fields.html.twigdefine a dedicated Twig block for the type, named by convention
<TypeIdentifier_field>. In our case,eztweet_fieldbe registered in parameters
The template: Resources/views/fields/eztweet.tpl
The first thing we will do is create the template. It will basically define the default display of a tweet. Remember that field type templates can be overridden in order to tweak what is displayed and how.
Each Field Type template receives a set of variables that can be used to achieve the desired goal. The variable we care about is field, an instance of eZ\Publish\API\Repository\Values\Content\Field. In addition to its own metadata (id, fieldDefIdentifier, etc.), it exposes the Field Value (Tweet\Value) through the value property.
This would work as a primitive template:
field.value.contents is piped through the raw twig operator, since the variable contains HTML code. Without it, the HTML markup would be visible directly, since twig escapes variables by default. Notice that we nest our code within a spaceless tag, so that we can format our template in a readable manner without jeopardizing the display with unwanted spaces.
Using the content fields helpers
Even though the above will work just fine, a couple of helpers will help us get something a bit more flexible. The EzPublishCoreBundle::content_fields.html.twig template, where the native Field Type templates are implemented, provides a couple of helpers: simple_block_field, simple_inline_field and field_attributes. The first two are used to display a field either as a block or inline. field_attributes makes it easier to use the attr variable that contains additional (HTML) attributes for the field.
Let's consider that we will display the value as a block element.
First, we need to make our template inherit from content_fields.html.twig. Then, we will create a field_value variable that will be used by the helper to print out the content inside the markup. And that's it. The helper will use field_attributes to add the HTML attributes to the generated div.
fieldValue is set to the markup we had above, using a {% set %} block. We then call the block function to process the simple_block_field template block.
Registering the template
As explained in the FieldType template documentation, a FieldType template needs to be registered in the eZ Publish semantic configuration. The most basic way to do this would be to do so in app/config/ezplatform.yml:
However, this is far from ideal. We want this to be part of our bundle, so that no manual configuration is required. For that to happen, we need to make our bundle extend the eZ Platform semantic configuration. To do so, we are going to make our bundle's dependency injection extension (DependencyInjection/EzSystemsTweetFieldTypeExtension.php) implement Symfony\Component\DependencyInjection\Extension\PrependExtensionInterface. This interface will let us prepend bundle configuration:
The last thing to do is move the template mapping from app/config/ezplatform.yml to Resources/config/ezpublish_field_templates.yml:
Notice that the ezpublish yaml block was deleted. This is because we already import our configuration under the ezpublish namespace in the prepend method.
You should now be able to display a content item with this Field Type from the frontoffice, with a fully functional embed:
