README.md

Scope Layout

The GlobalScreen service takes care of the mediation between the command classes and UI components and is responsible for assembling all necessary elements into a complete Page and submitting it to rendering.

Currently (ILIAS 6.0), the services and modules deliver their content via an ilGlobalPageTemplate, an implementation of the ilGlobalTemplateInterface. This is done for compatibility reasons. Internally, this instance delegates all relevant elements to the scope layout of the GlobalScreen service.

The Scope Layout assumes by default that a completely filled page is displayed. This page is filled with UI components, which in turn are filled with information from the other areas (e.g. MetaBar or MainBar). Now not all places in ILIAS need the same Page or all elements of a Page anymore. For this purpose, a developer can influence the composition of the page from his code before passing it to rendering.

He can do this for the whole page (e.g. without the MainBar) or he can provide a completely custom MainBar if required (e.g. LTI).

All possibilities to change the components of a page can be found via the GlobalScreen service in the DIC:

global $DIC;
$DIC->globalScreen()->layout()->factory()->...

Currently the following areas can be addressed:

• Page
• MetaBar
• MainBar
• BreadCrumbs
• Icon
• Content

Register modification

Like all other scopes, this scope works in the provider/collector procedure. In order to be able to make a change to the page, you implement your own ModificationProvider. These providers are ScreenContextAwareProviders, further information can be found at src/GlobalScreen/ScreenContext/README.md

<?php namespace ILIAS\Container\Screen;

//...

class MemberViewLayoutProvider extends AbstractModificationProvider implements ModificationProvider
{

    public function isInterestedInContexts() : ContextCollection
    {
        return $this->context_collection->repository();
    }

    public function getLogoModification(CalledContexts $screen_context_stack) : ?LogoModification
    {
        if (!$screen_context_stack->current()->hasReferenceId()) {
            return null;
        }

        $mv = ilMemberViewSettings::getInstance();
        if ($mv->isActive()) {
            return $this->globalScreen()->layout()->factory()->logo()->withModification(function (Image $current) use ($mv) : Image {
                $ref_id = $mv->getCurrentRefId();

                $image = $this->dic->ui()->factory()->image()->responsive("https://www.colourbox.com/preview/5559052-icon-user-red.jpg", "mv");
                if ($ref_id) {
                    $url = ilLink::_getLink(
                        $ref_id,
                        ilObject::_lookupType(ilObject::_lookupObjId($ref_id)),
                        array('mv' => 0)
                    );
                    $image = $image->withAction($url);
                }

                return $image;
            })->withHighPriority();
        }

        return null;
    }
}

The example returns - if in the ScreenContext 'repository', if a Ref-ID is present and if the MemberView is used in a course, – a change to the logo (which is only offered as an example until a dedicated message for it is offered in the UI service).

Since multiple ModificationProviders could modify the same area of the page at the same time, a priority is set for each modification (in this case ->withHighPriority()). Same priorities lead to an exception and it must be decided in JourFixe which of the two modifications gets the higher priority.

#Attention

The possibility of influencing the components of the "page" holds dangers:

• You can never be sure that you will not make any changes before or after the change.
• Do not use this option to bring menu items or Tools into the MainBar. Use the methods provided for this purpose as Providers in the respective scopes.