Specifying a Hyper-Reference

Dynamic View Services > Specifying Dynamic View Types > Hyper-References > Specifying a Hyper-Reference

Let us introduce hyper-references in the CompanyTree view type.

Example

view CompanyTree:

subscribe origin Company:

represent TreeR root:

HyperRef linkName={this->CompanyMatrix,identifier};

propagate departments;

subscribe Department:

represent TreeItemR item:

Ref<TreeR> ownerTree=company->root;

HyperRef linkName={this->DepartmentTable,name};

propagate employees;

...

The two linkName attributes for the root and item representations are hyper-references. As for any hyper-reference, they are defined in two parts linked by an arrow.

The first part of the expression specifies the view that must be opened when the hyper-reference is selected. It includes a server relation path and the name of a view type.

The second part is an expression whose string value is used to represent the hyper-reference on the component side.

In the code extract above, the view for the first linkName hyper-reference is the CompanyMatrix view of the company itself. The value represented is the identifier of the company. For the second linkName hyper-reference, the view is the DepartmentTable view of the department itself. The value represented is the department name.

Note that the specification

HyperRef linkName={this->CompanyMatrix,identifier};

is semantically equivalent to:

HyperRef linkName={CompanyMatrix,identifier};

Both linkName hyper-references are called local hyper-references, because their relation is explicitly or implicitly this. As with references, the relation path of a hyper-reference can be any transitive path of unary relations. For instance:

view DepartmentTable:

subscribe origin Department:

represent TableR table:

HyperRef title=

{company->CompanyTree,getFullName(company.identifier,name)};

...

In this example, the title attribute is a hyper-reference to the CompanyTree view defined on the target of the relation company of the Department object. Its label is the result returned by the function Department::getFullName. The hyper-reference attributes are declared to the representation model interpreter via a specific macro. For the title hyper-reference, the declaration is the following:

ILS_RP_OBJECT_BEGIN(TableR)

ILS_RP_ATTR_HREF(TableR,title,setTitle)

...

ILS_RP_OBJECT_END(TableR)

The function IlsSwRepresentation::setTitle declared to assign the hyper-reference is the same as the function declared to assign a string title. This is because the value of a hyper-reference attribute from the component point of view is its representation string.

Version 6.3