I

ILabelOwner

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Common interface for items in an IGraph implementation that may own labels.
ImplementsInheritance Hierarchy

Remarks

Like all items in an IGraph, this item supports the lookup method that can be used to query additional aspects of the item.

Examples

Relationship between label and label owner
// add a label to the owner
const label = graph.addLabel(owner, 'Some Text')

// the label's Owner property is set to the owner
console.log(label.owner === owner) // true
// the label is in its owner's Labels collection
console.log(owner.labels.includes(label)) // true

See Also

Developer's Guide

API

INode, IEdge, IPort, addLabel

Members

Show:

Properties

labels

: IListEnumerable<ILabel>
readonlyabstract
Gets a collection of labels that are owned by this instance.

This gives access to a read-only live view of the labels, i.e. the collection can change over time, as well as the labels contained in it. If a snapshot of the current state is needed, one needs to copy the collection and its contents.

To modify the label collection for instances of the default implementations that were created via the factory methods on IGraph, use addLabel and remove.

readonlyabstract

Examples

Adding labels to a node.
// add label with given text, default style, and default placement
// and determine the preferred size automatically

const label1 = graph.addLabel(node, 'Some Label')

// add label with given text, placement, style, size, and tag (user object)
const label2 = graph.addLabel(
  node,
  'Some Label',
  InteriorNodeLabelModel.CENTER,
  new LabelStyle(),
  new Size(10, 150),
  userObject,
)

// add label with given text and style but default placement
// and determine the preferred size automatically
const label3 = graph.addLabel({
  owner: node,
  text: 'Some Label',
  style: new LabelStyle(),
})
Iterating over all labels of a node.
for (const label of node.labels) {
  // ...
}
Removing a label from a node.
graph.remove(label)

See Also

Developer's Guide
API
addLabel, remove, owner

tag

: any
abstract
Gets or sets the tag object associated with this item instance.
The tag is an optional user-defined object which can be used to store arbitrary data related to this item. The item itself just provides the storage for the object.
abstract

Property Value

The user object associated with this item instance.

Examples

Setting a model item's tag
owner.tag = newTag
Getting the tag from a model item
const tag = owner.tag

See Also

Tags are presented in detail in the section The Graph Model.
Developer's Guide

Defined in

ITagOwner.tag

Methods

lookup

<T> (type: Constructor<T>): T
abstract
Returns an instance that implements the given type or null.
Typically, this method will be called to obtain a different view or aspect of the current instance. This is quite similar to casting or using a super type or interface of this instance, but is not limited to inheritance or compile-time constraints. An instance implementing this method is not required to return non-null implementations for the types, nor does it have to return the same instance any time. Also, it depends on the type and context whether the instance returned stays up to date or needs to be re-obtained for further use.
abstract

Parameters

type: Constructor<T>
the type for which an instance shall be returned

Return Value

T
an instance that is assignable to the type or null

See Also

Developer's Guide

Defined in

ILookup.lookup