com.yworks.yfiles.layout

Interface IEdgeLabelLayoutModel

All Known Implementing Classes:

DiscreteEdgeLabelLayoutModel, FreeEdgeLabelLayoutModel, SliderEdgeLabelLayoutModel

public interface IEdgeLabelLayoutModel

This interface defines the properties of the model associated with an IEdgeLabelLayout.

An IEdgeLabelLayoutModel provides a set of possible candidates for the placement of an edge label. It also defines a parameter that describes the current location of the label.

It is important that all state information is encapsulated in the model parameter. IEdgeLabelLayoutModel instances may be shared between multiple edge labels but produce different parameters for labels with different locations.

Method Summary

Modifier and Type	Method and Description
Object	createModelParameter(YOrientedRectangle labelBounds, IEdgeLayout edgeLayout, INodeLayout sourceLayout, INodeLayout targetLayout) Creates a model parameter that represents the given edge label position within this model.
Object	getDefaultParameter() Gets a model parameter that encodes the default position of this model's allowed edge label positions.
YList	getLabelCandidates(IEdgeLabelLayout labelLayout, IEdgeLayout edgeLayout, INodeLayout sourceLayout, INodeLayout targetLayout) Returns all EdgeLabelCandidates that describe valid label positions within this model.
YOrientedRectangle	getLabelPlacement(YDimension labelSize, IEdgeLayout edgeLayout, INodeLayout sourceLayout, INodeLayout targetLayout, Object parameter) Returns the oriented box of the label for the position encoded by the given model parameter.

Method Detail

createModelParameter

Object createModelParameter(YOrientedRectangle labelBounds,
                            IEdgeLayout edgeLayout,
                            INodeLayout sourceLayout,
                            INodeLayout targetLayout)

Creates a model parameter that represents the given edge label position within this model.

The created model parameter is the closest parameter representation of the given label location that can be achieved within this model.

This parameter can be passed to getLabelPlacement(YDimension, IEdgeLayout, INodeLayout, INodeLayout, Object) to retrieve the current label box.

A model parameter can be an arbitrary Object. However it must contain all information to allow restoring of the encoded location with this IEdgeLabelLayoutModel.

Parameters:

labelBounds - the oriented box of the label, encoding the label location for which the parameter should be created

edgeLayout - the layout of the edge to which the label belongs

sourceLayout - the layout of the source node of the label-owning edge

targetLayout - the layout of the target node of the label-owning edge

Returns:

the model parameter representing the given label location

See Also:

getLabelPlacement(YDimension, IEdgeLayout, INodeLayout, INodeLayout, Object)

getDefaultParameter

Object getDefaultParameter()

Gets a model parameter that encodes the default position of this model's allowed edge label positions.

This parameter can be passed to getLabelPlacement(YDimension, IEdgeLayout, INodeLayout, INodeLayout, Object) to retrieve the corresponding label box.

Returns:

the model parameter describing the default placement of the edge label

getLabelCandidates

YList getLabelCandidates(IEdgeLabelLayout labelLayout,
                         IEdgeLayout edgeLayout,
                         INodeLayout sourceLayout,
                         INodeLayout targetLayout)

Returns all EdgeLabelCandidates that describe valid label positions within this model.

In case the implementing IEdgeLabelLayoutModel allows every possible location, this method always returns the current location as a LabelCandidate.

Parameters:

labelLayout - the label for which candidates should be generated

edgeLayout - the layout of the edge to which the label belongs

sourceLayout - the layout of the source node of the label-owning edge

targetLayout - the layout of the target node of the label-owning edge

Returns:

a list of EdgeLabelCandidate instances

getLabelPlacement

YOrientedRectangle getLabelPlacement(YDimension labelSize,
                                     IEdgeLayout edgeLayout,
                                     INodeLayout sourceLayout,
                                     INodeLayout targetLayout,
                                     Object parameter)

Returns the oriented box of the label for the position encoded by the given model parameter.

The provided parameter must have been generated by this model.

Parameters:

labelSize - the width and height of the label

edgeLayout - the layout of the edge to which the label belongs

sourceLayout - the layout of the source node of the label-owning edge

targetLayout - the layout of the target node of the label-owning edge

parameter - the model parameter that describes the abstract position of the label within this model

Returns:

the oriented bounds of the label