TASK: Add docs about configuration of views

CodeExamples/localPackages/example_extension/Classes/Controller/ExampleController.php

@@ -31,6 +31,6 @@ class ExampleController extends ActionController
         // Comment the code out, to use fluid template from
         // "Resources/Private/Templates/Example/Example.html"
 
-        return 'Hello world!';
+        // return 'Hello world!';
     }
 }

Documentation/source/Views.rst

@@ -44,27 +44,175 @@ Do not forget to remote the ``return 'Hello world!';`` from our controller.
 
 We should now see our "Hello World!".
 
-Sections
---------
-
-ViewHelper
-----------
-
-Partials and Layouts
---------------------
-
 Configuration
 -------------
 
 Awesome, we now do no longer need to touch PHP code to change the output, we can use
 Fluid and an Integrator or Frontendler is able to change something.
 
-But they should be able to change template ins their own extension, e.g. a
-"sitepackage". Let's take a look how this works.
+But they should be able to change templates in their own extension, e.g. a
+"sitepackage". We will see how to do this in next chapter "Configuration".
+
+Sections
+--------
+
+If templates grow in size, we need to add some structure. One way is to use sections
+inside a single Template. A section is like a PHP method or function and can be
+called with arguments:
+
+.. code-block:: html
+   :linenos:
+
+   Normal output
+
+   {f:render(
+      section: 'FirstSection',
+      arguments: {
+         arg1: var1,
+         arg2: var2,
+         arg3: 'string'
+      }
+   )}
+
+   <f:section name="FirstSection">
+      Some output + {arg1}.
+   </f:section>
+
+We have our default output "Normal output" and call a ViewHelper ``f:render`` with
+some arguments to render a specific section with some arguments. The ViewHelper will
+be replaced with the rendered result of the section.
+
+This way it's possible to structure templates like Controllers. They control the
+output flow and call different sections with arguments where more specific logic
+happens.
+
+Variables
+---------
+
+Variables are assigned via PHP:
+
+.. code-block:: php
+   :linenos:
+
+   // Inside a controller action do:
+   $this->view->assign('var1', $variable1);
+   $this->view->assign('var2', $variable2);
+
+   // Or to assign multiple variables at once:
+   $this->view->assignMultiple([
+       'var1' => $variable1
+       'var2' => $variable2
+   ]);
+
+Assigned variables can be accessed inside Fluid with curly braces:
+
+.. code-block:: html
+   :linenos:
+
+   Hello {userInput}!
+
+ViewHelper
+----------
+
+To make Templates more flexible, ViewHelpers are available. They are custom HTML-Tags
+available inside via template engine.
+TYPO3 and Fluid already ship some ViewHelpers, but you can provide own ViewHelpers.
+
+ViewHelpers always live in a Namespace, e.g. ``TYPO3\CMS\Fluid\ViewHelpers`` or
+``Workshop\\ExampleExtension\\ViewHelpers``.
+
+You can either register these namespaces globally, or inside the templates via
+``{namespace wee=Workshop\ExampleExtension\ViewHelpers}``.
+The ``f`` namespace for ``Fluid`` is always registered globally.
+
+Once ViewHelpers are available available, you can use them:
+
+.. code-block:: html
+
+   <f:format.crop maxCharacters="5">Hello World!</f:format.crop>
+
+The above should output "Hello ...", as the string is cropped to 5 characters, the
+"..." can be configured via another argument of the ViewHelper:
+
+.. code-block:: html
+
+   <f:format.crop maxCharacters="5" append="">Hello World!</f:format.crop>
+
+Beside the tag based kind of inserting ViewHelpers, you can also use the "inline
+notation":
+
+.. code-block:: html
+   :linenos:
+
+   {f:format.date(date: 'now')}
+
+It's also possible to chain ViewHelpers in both ways:
+
+.. code-block:: html
+   :linenos:
+
+   {f:format.date(date: 'now') -> f:format.raw()}
+
+   <f:format.raw>
+      {f:format.date(date: 'now')}
+   </f:format.raw>
+
+   <f:format.raw>
+      <f:format.date date="midnight" />
+   </f:format.raw>
+
+   <f:format.raw>
+      <f:format.date>midnight</f:format.date>
+   </f:format.raw>
+
+Partials and Layouts
+--------------------
+
+We already saw sections to make a single template easier to manage.
+For re-using parts between multiple templates there are Partials.
+
+Partials are like Templates and can be rendered via:
+
+.. code-block:: html
+   :linenos:
+
+   Normal output
+
+   {f:render(
+      partial: 'Path/To/Partial',
+      arguments: {
+         arg1: var1,
+         arg2: var2,
+         arg3: 'string'
+      }
+   )}
+
+
+Also each template can be embedded into a Layout via:
+
+.. code-block:: html
+   :linenos:
+
+   <f:layout name="Layout/Path/AndName" />
+
+This way wrapping code, e.g. for HTML E-Mails or content elements can be moved to a
+layout and all templates can inherit this layout.
 
 Further resources
 -----------------
 
+.. hint::
+
+   Use ViewHelpers for output logic, not to get data into your View.
+
+   Use Controller and DataProcessing to prepare data.
+
+* Available ViewHelpers can be found at:
+
+  * :file:`typo3/sysext/fluid/Classes/ViewHelpers/`
+
+  * :file:`vendor/typo3fluid/src/ViewHelpers/`
+
 * https://github.com/TYPO3/Fluid
 
 * https://docs.typo3.org/typo3cms/TyposcriptReference/ContentObjects/Fluidtemplate/Index.html