Wrapper link type

Wrapper link types are used to represent existing or computable links (e.g. project – project leader) in the Vertec model. This means that an existing link is made visible on the surface.

If you want to create connections that do not exist by default in the Vertec model, create a Custom Link Type instead.

Wrapper link types do two things:

• Existing wrapper link types can be modified. For example, if you do not want to work with activities in Vertec, the corresponding wrapper link types can be disabled and lists no longer appear on the interface.
• New wrapper link types can be created to show the user information in the right place. For example, you can create a wrapper link type that allows the project leader to get an overview of the activities of his or her active projects.

Here is an example of a predefined wrapper link type:

In a link type, the behavior of the two sides (Role) of the link must always be defined, so the window essentially consists of the two parts From and After, which define the two sides of the link type.

Field	Significance
designation	The designation entered here will be shown on the interface for this Role. Here in the example, the so-called Link Container displays Own Projects:
Order	Here you can specify the sorting in the tree. Vertec sorts the link containers in ascending order. If nothing is specified, the containers are sorted alphabetically. The order can also be edited in the Standard line.
Icon (disambiguation)	Here you can specify the icon that the container should show.
Class name	Name of the record type (class) of this Role. Can be assigned via the selection field.
Linkmember	See separate section Linkmember below.
Expression	Specifies the expression how to get to this end from the other side. In the example, the project user (class name in After) navigates to projects with the expression ownprojects->select(active). As you can see, more complex expressions can also be used here.
Container class	Instead of the standard wrapper-link container, special container classes can be specified depending on the class. A list of container classes can be found here.
'new’ Menu	If this option is selected, the option to create a new entry and link it immediately appears in the New menu. Please also see the section about link members.
Show Container	If this option is checked, a container (subfolder) will be displayed as soon as links are present. It may be useful not to display both sides for some links, then this option can be deselected for a Role.
Always show container	If this option is selected in addition to Show Container, the container will always be shown regardless of whether links exist or not. An example of such a Role is the list of open services on project users. The container for invoices on projects, on the other hand, will only be shown when invoices exist. For this Role, this option is not selected. Especially for links to users, it makes sense to always show containers. Otherwise, Vertec must always check whether the container needs to be shown or not, which can have an impact on performance.
active	Only active link types are displayed on the interface. An existing wrapper link type can also be disabled with the Standard line.
Allow links	This type of link may be used to create new links between entries by Drag-and-drop be created. Please also see the section about the linkmember.

Sometimes you have to work with complicated expressions, expressions that filter or go over several levels, for example. If you specify an expression for a link type that consists of more than just the member, you have to specify a link member. This has the following functions:

• If the Allow links option is activated, Vertec needs the link member to know to which member it has to link the entry when linking two entries via drag & drop.
• If the 'New’ menu option is set, Vertec needs the link member to know with which member it must link the entry when creating a new entry.
• This means that the link member must be the association to which the “counter-entry” is attached. A single member (field) cannot be a link member (see example below).
• Permission check: The link type determines via the link member whether the container should be shown and whether new links are allowed or not. This means that the link member must be set to something that the corresponding users have user rights to view. When checking whether the link should be shown, read permission is checked, while when determining whether new links are allowed, write permission is checked.

  In such cases, if no link member is specified or if the user does not authorize to do so, the link will not be visible to the user nor can it be set. The link will then only be visible to administrators.

In this example, the lower part of the link type is a complicated expression projectactivities->union(activities). In order for Vertec to know which member it is, the linkmember projectactivities is specified. This means: If you drag and drop an activity onto a project and select Role:Activities, the project is assigned to the activity as a project:

The link member always refers to the view from the other side. In this example, this means project activities.

Another example is invoices on own projects. The expression ownprojects.invoices is not shown on non-project administrators if the link member is not set to something readable.

Here, for example, eigenprojekte can be used. If the user has (read) permission, the link will be shown on the interface. The link member no longer matches the result (an invoice is not part of eigenprojekte). Therefore, a link cannot be made directly, the option Allow links must be deactivated on such a link type.