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The ILIAS UI-Framework

The ILIAS UI-Framework helps you to implement GUIs consistent with the guidelines of the Kitchen Sink.

Use Kitchen Sink Concepts

The ILIAS UI-Framework deals with the concepts found in the Kitchen Sink. In fact, this framework and the Kitchen Sink are heavily related. You won’t need to think about HTML if you’re using this framework. You also won’t need to think about the implementation you are using, the device your GUI is displayed on or the CSS-classes you need to use. You will be able to talk to other people (like users or designers) using the same concepts and problem space as they do. This is also not a templating framework.

Compose GUIs from Simple Parts

In the ILIAS UI-Framework, GUIs are described by composing large chunks from smaller components. The available components and their possible compositions are described in the Kitchen Sink. The single components only have little configuration, complex GUIs emerge from simple parts. You also won’t need to modify existing components, just use them as provided.

Correctness by Construction and Testability

The design of the ILIAS UI-Framework makes it possible to identify lots of guideline violations during the construction of a GUI and turn them into errors or exceptions in PHP. This gives you the freedom to care about your GUI instead of the guidelines it should conform to. You also can check your final GUI for Kitchen Sink compliance using the procedures the framework provides for Unit Testing.

Using the Framework

As a user of the ILIAS UI-Framework your entry point to the framework is provided via the dependency injection container $DIC->ui()->factory(), which gives you access to the main factory implementing ILIAS.

How to Discover the Components in the Framework?

The factories provided by the framework are structured in the same way as the taxonomy given in the KS-Layout. The main factory provides methods for every node or leaf in the Class-Layer of the Kitchen Sink Taxonomy. Using that method you get a sub factory if methods corresponds to a node in the layout. If the method corresponds to a leaf in the layout, you get a PHP representation of the component you chose. Since the Jour Fixe decides upon entries in the Kitchen Sink, the factories in the framework only contain entries Accepted by the JF. Creating a component with the framework thus just means following the path from the Class to the leaf you want to use in your GUI.

The entries of the Kitchen Sink are documented in this framework in a machine readable form. That means you can rely on the documentation given in the interfaces to the factories, other representations of the Kitchen Sink are derived from there. This also means you can chose to use the documentation of the Kitchen Sink in ILIAS to check out the components.

How to Use the Components of the Framework?

With the ILIAS UI-Framework you describe how your GUI is structured instead of instructing the system to construct it for you. The main principle for the description of GUIs is composition.

You declare you components by providing a minimum set of properties and maybe other components that are bundled in your component. All compents in the framework strive to only use a small amount of required properties and provide sensible defaults for other properties.

Since the representation of the components are implemented as immutable objects, you can savely reuse components created elsewhere in your code, or pass your component to other code without being concerned if the other code modifies it.

Example 1 Example 2

Implementing Elements in the Framework

As an implementor of components in the ILIAS UI-Framework you need to stick to some rules, to make sure the framework behaves in a uniform and predictable way accross all components. Since a lot of code will rely on the framework and the Kitchen Sink is coupled to the framework, there also are processes to introduce new components in the framework and modify existing components.

How to Introduce a New Component?

New components are introduced in the UI-Framework and the Kitchen Sink in parallel to maintain the correspondence between the KS and the UI-Framework.

An entry in the Kitchen Sink passes through three states:

These states are represented by using functionality of git and GitHub. After acceptance, the new entry is part of the Kitchen Sink as well as part of the source code in the trunk.

How to Implement a Component?

If you would like to implement a new component to the framework you should perform the following tasks:

  1. Add your new component into the respective factory interface. E.g. If you introduce a component of a completely new type, you MUST add the description to the main factory (src/UI/Factory.php). If you add a new type of a button, you MUST add the description to the existing factory for buttons, located at src/UI/Component/Button/Factory.

  2. The description MUST use the following template:

    /**
    * ---
    * description:
    *   purpose: What is to be done by this control
    *   composition: What is this control composed of
    *   effect: What happens if the control is operated
    *   rivals:
    *     Rival 1: What other controls are similar, what is their distinction
    *
    * background: Relevant academic information
    * context: 
    *     - The context states: where this control is used specifically with examples (this list might not be complete) and how common is this control used
    *
    * rules:
    *   usage:
    *     1: Where and when an element is to be used or not.
    *   composition:
    *     1: How this component is to be assembled.
    *   interaction:
    *     1: How the interaction with this object takes place.
    *   wording:
    *     1: How the wording of labels or captions must be.
    *   style:
    *     1: How this element should look like.
    *   ordering:
    *     1: How different elements of this instance are to be ordered.
    *   responsiveness:
    *     1: How this element behaves on changing screen sizes
    *   accessibility:
    *     1: How this element is made accessible
    *
    * ---
    * @param   string $content
    * @return \ILIAS\UI\Component\Demo\Demo
    **/
    public function demo($content);
  3. This freshly added function in the factory leads to an error as soon as ILIAS is opened, since the implementation of the factory (located at src/UI/Implementation/Factory.php) does not implement that function yet. For the moment, implement it, as follows:

    /**
    * @inheritdoc
    */
    public function demo($content)
    {
        throw new \ILIAS\UI\NotImplementedException();
    }
  4. Next, you should think about the interface you would like to propose for this component. You need to model the component you want to introduce by defining its interface and the factory method that constructs the component. To make your component easy to use, it should be creatable with a minimum of parameters and use sensible defaults for the most of its properties. Also think about the use cases for your component. Make typical use cases easy to implement and more special use cases harder to implement. Put getters for all properties on your interface. Make sure you understand, that all UI components should be immutable, i.e. instead of defining setters setXYZ you must define mutators withXYZ that return copies of your component with changed properties. Try to use as little mutators as possible and try to make it easy to maintain the invariants defined in your rules when mutators will be used. Take care to keep it as minimal as possible. At a description for each function. For the demo component, this interface could look as follows (located at (src/UI/Component/Demo/Demo.php): ``` php <?php namespace ILIAS;

    /**

  5. Make sure all tests are passing by executing ’‘’phpunit tests/UI’’’. For the demo component this means we have to add the following line to NoUIFactory in tests/UI/Base.php: php public function demo($demo){}

  6. Congratulations, at this point you are ready to present your work to the JF. Create a PR named “UI NameOfTheComponent”. To make it easy for non-developers to follow the discussion, you MUST link to the changed/added factory classes and mock in the description you provide for your PR. Further, it would be wise to enhance your work with a little mockup. This makes it much easier to discuss the new component at the JF. So best create such an example located and also link it in your comment, e.g. at src/UI/examples/Demo/mockup.php: php <?php function mockup() { return "<h1>Hello Demo!</h1>"; } If needed, you can also add JS-logic (e.g. src/UI/examples/Demo/mockup.php): php <?php function script() { return "<script>console.log('Hello Demo');</script>Open your JS console!"; } However best might be to just provide a screenshoot showing what the component will look like: ``` php function mockup() { global $DIC; $f = $DIC->ui()->factory(); $renderer = $DIC->ui()->renderer();

     $mockup = $f->image()->responsive("src/UI/examples/Demo/mockup.png");
     return $renderer->render($mockup);

    } ```

  7. Next you should create the necessary tests for the new component. At least provide tests for all interface methods and the rendering. For the demo component this looks as follows (located at tests/UI/Component/Demo/DemoTest.php):

     <?php
    
     require_once(__DIR__."/../../../../libs/composer/vendor/autoload.php");
     require_once(__DIR__."/../../Base.php");
    
     use \ILIAS\UI\Component as C;
    
     /**
      * Test on demo implementation.
      */
     class DemoTest extends ILIAS_UI_TestBase {
    
         public function test_implements_factory_interface() {
             $f = new \ILIAS\UI\Implementation\Factory();
    
             $this->assertInstanceOf("ILIAS\\UI\\Factory", $f);
             $demo = $f->demo("Demo Implementation!");
             $this->assertInstanceOf( "ILIAS\\UI\\Component\\Demo\\Demo", $demo);
         }
    
         public function test_get_content() {
             $f = new \ILIAS\UI\Implementation\Factory();
             $demo = $f->demo("Demo Implementation!");
    
             $this->assertEquals($demo->getContent(), "Demo Implementation!");
         }
    
         public function test_render_content() {
             $r = $this->getDefaultRenderer();
             $f = new \ILIAS\UI\Implementation\Factory();
             $demo = $f->demo("Demo Implementation!");
    
    
             $html = $r->render($demo);
    
             $expected_html = '<h1 class="il-demo">Demo Implementation!</h1>';
    
             $this->assertHTMLEquals($expected_html, $html);
         }
     }
  8. Currently you will only get the NotImplementedException you throwed previously. That needs to be changed. First, add an implementation for the new interface (add it at src/UI/Implementation/Component/Demo/Demo.php): ``` php checkStringArg(“title”, $content);

         $this->content = $content;
     }
    
     /**
      * @inheritdoc
      */
     public function getContent(){
         return $this->content;
     }

    } ```

  9. Next, make the factory return the new component (change demo() of src/UI/Implementation/Factory.php):

    return new Component\Demo\Demo($content);
  10. Then, implement the renderer at src/UI/Implementation/Component/Demo/Demo.php:

    <?php
    
    /* Copyright (c) 2016 Timon Amstutz <timon.amstutz@ilub.unibe.ch> Extended GPL, see docs/LICENSE */
    
    namespace ILIAS\UI\Implementation\Component\Demo;
    
    use ILIAS\UI\Implementation\Render\AbstractComponentRenderer;
    use ILIAS\UI\Renderer as RendererInterface;
    use ILIAS\UI\Component;
    
    class Renderer extends AbstractComponentRenderer {
        /**
         * @inheritdocs
         */
        public function render(Component\Component $component, RendererInterface $default_renderer) {
            $this->checkComponent($component);
            $tpl = $this->getTemplate("tpl.demo.html", true, true);
            $tpl->setVariable("CONTENT",$component->getContent());
            return $tpl->get();
        }
    
        /**
         * @inheritdocs
         */
        protected function getComponentInterfaceName() {
            return array(Component\Demo\Demo::class);
        }
    }
  11. Finally you need the template used to render your component. Create it at src/UI/templates/default/Demo/tpl.demo.html: php <h1 class="il-demo">{CONTENT}</h1>

  12. Execute the UI tests again. At this point, everything should pass. Thanks, you just made ILIAS more powerful!

  13. Optional: It is possible good to add an examples demonstrating the usage of your new component. The example for the demo looks as follows (located at src/UI/examples/Demo/render.php):

      <?php
      function render() {
          //Init Factory and Renderer
          global $DIC;
          $f = $DIC->ui()->factory();
          $renderer = $DIC->ui()->renderer();
    
          $demo = $f->demo("Demo rendered by template!");
    
    
          return $renderer->render($demo);
      }
  14. Optional: You might need to add some less, to make your new component look nice. However, only do that if this is really required. Use bootstrap classes as much as possible. If you really need to add additional less, use existing less variables whenever appropriate. If you add a new variable, add the il- prefix to mark the as special ILIAS less variable and provide the proper description. For the demo this could look as follows (located at src/UI/templates/default/Demo/demo.less): less .il-demo{ color: @il-demo-color; }

  15. Include the new less file to delos (located at templates/default/less/delos.less): less @import "@{uibase}Demo/demo.less";

  16. Optional add the new variables to the variables.less file (located at templates/default/less/variables.less): less //== Demo Component // //## Those variables are only used for demo purposes //** Color of the text shown in the demo @il-demo-color: @brand-danger;

  17. Optional: Recompile the less to see the effect by typing lessc templates/default/delos.less > templates/default/delos.css

  18. Optional: If your component introduces a new factory, do not forget to wire it up in the according location of the initialisation. Have a look into ilInitialisation::initUIFramework in Services/Init/class/class.ilInitialisation.php.

How to Change an Existing Component?

TODO: write me

Abstraction of Javascript in the Framework

Note: The concept described in this section is not yet fully finalized.

The functionality of some components relies on javascript. As an example, a modal is showed and closed by clicking on some triggerer component. As a user of the framework, you should not worry about writing the javascript logic for this kind of interactions.

About Triggerables, Triggerer and Signals

Before describing the concept in more detail, you should be aware of the following definitions: * Signal A signal describes a javascript action of a component which can be triggered by another component of the framework. * Triggerable A component offering some signals that can be triggered by other components. * Triggerer A component triggering a signal of another component. * Event The javascript event on which a signal is being triggered, e.g. click, hover etc.

Again, consider the example if a user opens a modal by clicking on a button:

How to trigger Signals of Components

This code snippet shows how to open a modal by clicking on a button:

$modal = $factory->modal()->roundtrip('Title', $factory->legacy('Hello World'));
$button = $factory->button()->standard('Open Modal', '#')
  ->withOnClick($modal->getShowSignal());

The button is a triggerer component. As such, it offers the method withOnClick which takes any Signal offered by a triggerable. This is how the framework connects triggerer components with signals of triggerable components. Similar to the click event, there exist methods withOnHover and withOnLoad to abstract the javascript events on which a signal is being triggered.

Attention: Immutable Objects and Signals

Each triggerer component stores the signals it triggers. By cloning a component, these signals are cloned as well. This means that a cloned component may trigger the same signals as the original. Consider the following example: php $modal = $factory->modal()->roundtrip('Title', $factory->legacy('Hello World')); $button1 = $factory->button()->standard('Open Modal', '#') ->withOnClick($modal->getShowSignal()); $button2 = $button1->withLabel('Open the same Modal'); In the example above, $button2 will open the same modal as $button1. In order to reset any triggered signals, use the method $button2->withResetTriggeredSignals().

Implementing a Triggerer Component

Any component acting as triggerer must implement the Triggerer interface. This interface is further extended by interfaces describing the javascript event on which a signal is being triggered. Currently, there exist the Clickable, Hoverable and Onloadable interfaces. Please check out the button component for an example implementation.

Implementing a Triggerable Component

Any component acting as triggerable must implement the Triggerable interface. In addition, it must offer at least one signal that can be triggered by other components. The renderer of the triggerable component is also responsible to execute the javascript logic if any signal is getting triggered. Please check out the modal component for an example implementation. The next section explains how the concept of signals/triggerer/triggerable is abstracted in javascript.

Technical Details

The magic how everything is glued together on the javascript side takes part in the renderers of the triggerer and triggerable components: * Triggerer: The renderer of the triggerer component knows which signals are triggered on which events. It registers a new event handler on the component (e.g. on click/hover) which will trigger the signal as a custom javascript event. * Triggerable: The renderer of the triggerable component knows the signals and the javascript logic which must be executed if any of the signals is getting triggered.

Each signal has a unique alphanumeric ID. The triggerer uses this ID to trigger a custom javascript event which will be handled by some event handler from the triggerable. In order to understand this concept, take a look at the javascript code that is getting generated by the renderers if a button opens a modal on click:

Renderer of button
The renderer of the button generates the HTML for the button AND registers the event handler for the button click. This event handler triggers a custom javascript event with the same name as the ID of show signal of the modal: <button id="button1">Open Modal</button> <script> $('#button1').on('click', function() { $(this).trigger('id_of_signal_to_open_the_modal', { 'id' : 'id_of_signal_to_open_the_modal', 'triggerer' : $(this), 'event' : 'click', 'options' : {} } return false; }); </script> Note that some event data is passed with the event, such as the triggerer, event and event options. This allows the event handler of the modal to identify the triggerer.

Renderer of modal
The renderer of the modal generates the HTML for the modal AND registers an event handler on the ID of the show signal. The event handler calls some javascript logic to show the modal.

<div class="modal" id="modal1"> ... </div>
<script>
$(document).on('id_of_signal_to_open_the_modal', function(event, signalData) { 
  il.UI.modal.showModal('modal1', signalData);
});
</script>

Note: signalData contains the event data passed by the triggerer, e.g. signalData.triggerer holds the JQuery object of the button.

For more information on events in javascript, in the context of JQuery: http://api.jquery.com/category/events/

FAQ

There are so many rules, is that really necessary?

The current state of the art in ILIAS GUI creation was dubbed “The GUI Anarchy” by some smart person. The introduction of the ILIAS UI framework aims at bringing more structure in the GUIs of ILIAS. As one (or two) maintainers for all things GUI of ILIAS is no option for several reasons and the current state (without rules) is anarchy, rules seem to be the only sensible option to get some structure. All exisiting rules have a purpose, but there might be a more terse way to explain them. If you have found it, we’ll be glad to accept your PR.

How do I know where my component is rendered?

For some use cases you might get to the point where you want to know where your component is rendered to emit different HTML in your renderer. A general idea of the UI framework is that components have their unique look that is recognisable throughout the system, which is the exact reason you could not find a simple way to get to know where your component is rendered.

There still might be circumstances where a context dependent rendering is indeed required. The Renderer offers a withAdditionalContext method for that purpose, which can be used to alter the selection of the renderer for your component. Before using it, consider if you really require a different look in a different context and, if that is indeed the case, whether you could achieve the same effect by using CSS. The class FSLoader contains directions how to introduce new renderers for different contexts in your component.

I don’t understand that stuff, is there anyone who can explain it to me?

Yes. Ask Richard Klees richard.klees@concepts-and-training.de or Timon Amstutz timon.amstutz@ilub.unibe.ch.