com.yworks.yfiles.graph.labelmodels

Class EdgeSegmentLabelModel

java.lang.Object

com.yworks.yfiles.graph.labelmodels.EdgeSegmentLabelModel

All Implemented Interfaces:

ILookup, ILabelModel, ILabelModelParameterFinder, ILabelModelParameterProvider

public class EdgeSegmentLabelModel
extends Object
implements ILabelModel, ILabelModelParameterProvider, ILabelModelParameterFinder

An edge label model that allows placement of labels relative to an edge segment at a set of continuous positions at specified sides of the edge path.

The set of positions can be influenced by specifying the SideOfEdge value that controls on which side of the edge labels positions should be considered. Furthermore, it's possible to specify distance values that control the distance between label and edge and between label and nodes.

If a label model parameter is created EdgeSides.ON_EDGE, the label's center is usually placed on the edge. It can be shifted by specifying a Offset value but the Distance value is ignored. For all other values of EdgeSides the total distance between the label bounds and the edge path is the sum of Offset and Distance.

The label placements use a specified segment index from the source or target side and a ratio on this segment. This is the main difference to the EdgePathLabelModel which only uses a ratio value of the full edge path.

Field Summary

Fields inherited from interface com.yworks.yfiles.graph.ILookup

EMPTY

Constructor Summary

Constructors

Constructor and Description
EdgeSegmentLabelModel() Returns a new instance of EdgeSegmentLabelModel.
EdgeSegmentLabelModel(double distance, double offset, double angle, boolean autoRotationEnabled, EdgeSides sideOfEdge) Initializes a new instance of the EdgeSegmentLabelModel class.

Method Summary

Modifier and Type	Method and Description
ILabelModelParameter	createDefaultParameter() A model parameter that encodes the default position of this model's allowed edge label positions.
ILabelModelParameter	createParameterFromCenter(double segmentRatio, EdgeSides sideOfEdge) Creates a parameter where the label is attached to the edge segment that contains the edge's midpoint.
ILabelModelParameter	createParameterFromSource(int segmentIndex, double segmentRatio, EdgeSides sideOfEdge) Creates a parameter that measures the provided segment index from the source side of the edge path.
ILabelModelParameter	createParameterFromTarget(int segmentIndex, double segmentRatio, EdgeSides sideOfEdge) Creates a parameter that measures the provided segment index from the target side of the edge path.
ILabelModelParameter	findBestParameter(ILabel label, ILabelModel model, IOrientedRectangle layout) Tries to find a parameter that best matches the given layout for the provided label instance.
double	getAngle() Gets the rotation angle of all labels with this model in radians.
ILookup	getContext(ILabel label, ILabelModelParameter layoutParameter) Returns an empty context.
double	getDistance() Gets the distance between the label box and the edge path.
IOrientedRectangle	getGeometry(ILabel label, ILabelModelParameter layoutParameter) Calculates the geometry of the given label using the given model parameter.
double	getOffset() Gets the offset of the label box and the edge path relative to the default placement.
IEnumerable<ILabelModelParameter>	getParameters(ILabel label, ILabelModel model) Returns an enumerator over a set of possible ILabelModelParameter instances that can be used for the given label and model.
EdgeSides	getSideOfEdge() Gets the side placement specifiers for edge labels.
boolean	isAutoRotationEnabled() Gets whether edge labels are automatically rotated according to the angle of the corresponding reference edge segment.
<TLookup> TLookup	lookup(Class<TLookup> type) Returns an instance that implements the given type or null.
void	setAngle(double value) Sets the rotation angle of all labels with this model in radians.
void	setAutoRotationEnabled(boolean value) Sets whether edge labels are automatically rotated according to the angle of the corresponding reference edge segment.
void	setDistance(double value) Sets the distance between the label box and the edge path.
void	setOffset(double value) Sets the offset of the label box and the edge path relative to the default placement.
void	setSideOfEdge(EdgeSides value) Sets the side placement specifiers for edge labels.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.yworks.yfiles.graph.ILookup

createDictionaryLookup, createDynamic, createSingle, createSingle, createWrapped, lookup, lookup, safeLookup

Constructor Detail

EdgeSegmentLabelModel

public EdgeSegmentLabelModel()

Returns a new instance of EdgeSegmentLabelModel.

EdgeSegmentLabelModel

public EdgeSegmentLabelModel(double distance,
                             double offset,
                             double angle,
                             boolean autoRotationEnabled,
                             EdgeSides sideOfEdge)

Initializes a new instance of the EdgeSegmentLabelModel class.

Parameters:

distance - the distance to the edge.

offset - the offset to the default placement.

angle - the angle of the label's rotation in radians.

autoRotationEnabled - if set to true auto rotation is enabled.

sideOfEdge - the side of the edge labels.

Method Detail

createDefaultParameter

public final ILabelModelParameter createDefaultParameter()

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

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

Specified by:

createDefaultParameter in interface ILabelModel

Returns:

a parameter for this model instance

createParameterFromCenter

public final ILabelModelParameter createParameterFromCenter(double segmentRatio,
                                                            EdgeSides sideOfEdge)

Creates a parameter where the label is attached to the edge segment that contains the edge's midpoint.

Parameters:

segmentRatio - The ratio at which to place the label at the segment. A ratio of 0.0 will place the label at the source side of the segment, a ratio of 1.0 at the target side. Ratios < 0.0 or > 1.0 will be interpreted as absolute values in world coordinates.

sideOfEdge - The side of the edge the label is placed on. Note that only single enum values but no combined ones are allowed.

Returns:

A label parameter that describes the provided parameters for this model instance.

createParameterFromSource

public final ILabelModelParameter createParameterFromSource(int segmentIndex,
                                                            double segmentRatio,
                                                            EdgeSides sideOfEdge)

Creates a parameter that measures the provided segment index from the source side of the edge path.

Parameters:

segmentIndex - The zero-based index of the segment beginning from the source side.

segmentRatio - The ratio at which to place the label at the segment. A ratio of 0.0 will place the label at the source side of the segment, a ratio of 1.0 at the target side. Ratios < 0.0 or > 1.0 will be interpreted as absolute values in world coordinates.

sideOfEdge - The side of the edge the label is placed on. Note that only single enum values but no combined ones are allowed.

Returns:

A label parameter that describes the provided parameters for this model instance.

createParameterFromTarget

public final ILabelModelParameter createParameterFromTarget(int segmentIndex,
                                                            double segmentRatio,
                                                            EdgeSides sideOfEdge)

Creates a parameter that measures the provided segment index from the target side of the edge path.

Parameters:

segmentIndex - The zero-based index of the segment beginning from the target side.

segmentRatio - The ratio at which to place the label at the segment. A ratio of 0.0 will place the label at the target side of the segment, a ratio of 1.0 at the source side. Ratios < 0.0 or > 1.0 will be interpreted as absolute values in world coordinates.

sideOfEdge - The side of the edge the label is placed on. Note that only single enum values but no combined ones are allowed.

Returns:

A label parameter that describes the provided parameters for this model instance.

findBestParameter

public final ILabelModelParameter findBestParameter(ILabel label,
                                                    ILabelModel model,
                                                    IOrientedRectangle layout)

Description copied from interface: ILabelModelParameterFinder

Tries to find a parameter that best matches the given layout for the provided label instance.

This method may not necessarily find a parameter that matches the provided layout exactly. Implementations may choose to simply return the model's default parameter but may never return null.

Specified by:

findBestParameter in interface ILabelModelParameterFinder

Parameters:

label - The label to find a parameter for.

model - The model instance to use. This should be the instance this instance has been obtained from.

layout - The anticipated layout for the label.

Returns:

A non-null parameter that can be used for the label to approximate the provided layout.

getAngle

public final double getAngle()

Gets the rotation angle of all labels with this model in radians.

Returns:

The rotation angle of all labels with this model in radians.

See Also:

setAngle(double)

getContext

public final ILookup getContext(ILabel label,
                                ILabelModelParameter layoutParameter)

Returns an empty context.

Specified by:

getContext in interface ILabelModel

Parameters:

label - The label to use in the context.

layoutParameter - The parameter to use for the label in the context.

Returns:

An empty context.

See Also:

ILookup.EMPTY

getDistance

public final double getDistance()

Gets the distance between the label box and the edge path.

The interpretation of the values depends on the SideOfEdge of the individual ILabelModelParameter.

Note that for EdgeSides.ON_EDGE this property is ignored. For all other values of EdgeSides the Offset property is added to this distance.

Returns:

The distance between the label box and the edge path.

See Also:

getSideOfEdge(), EdgeSides, getOffset(), setDistance(double)

getGeometry

public final IOrientedRectangle getGeometry(ILabel label,
                                            ILabelModelParameter layoutParameter)

Description copied from interface: ILabelModel

Calculates the geometry of the given label using the given model parameter.

Specified by:

getGeometry in interface ILabelModel

Parameters:

label - The label to calculate the geometry for.

layoutParameter - A parameter that is compatible with this model. Typically, this is a parameter that has been created by this model, and its property Model returns this instance.

Returns:

An IOrientedRectangle that describes the geometry of the label. This is typically designed as a flyweight, therefore clients should not cache the instance but store the values if they need a snapshot for later use.

getOffset

public final double getOffset()

Gets the offset of the label box and the edge path relative to the default placement.

For EdgeSides.ON_EDGE this is the offset between the center of the label box and the edge path. For all other EdgeSides values this offset is added to the Distance property which results in the total distance between the label box and the edge path.

Returns:

The offset of the label box and the edge path relative to the default placement.

See Also:

getSideOfEdge(), EdgeSides, setOffset(double)

getParameters

public final IEnumerable<ILabelModelParameter> getParameters(ILabel label,
                                                             ILabelModel model)

Description copied from interface: ILabelModelParameterProvider

Returns an enumerator over a set of possible ILabelModelParameter instances that can be used for the given label and model.

Specified by:

getParameters in interface ILabelModelParameterProvider

Parameters:

label - The label instance to use.

model - The model to provide parameters for.

Returns:

A possibly empty enumerator over a set of label model parameters.

getSideOfEdge

public final EdgeSides getSideOfEdge()

Gets the side placement specifiers for edge labels.

The label model parameter finder and provider returned by lookup(Class) consider the specified sides.

Returns:

The SideOfEdge.

See Also:

EdgeSides, setSideOfEdge(EdgeSides)

isAutoRotationEnabled

public final boolean isAutoRotationEnabled()

Gets whether edge labels are automatically rotated according to the angle of the corresponding reference edge segment.

By default, this feature is enabled.

Returns:

true if edge labels are automatically rotated; false otherwise.

See Also:

setAutoRotationEnabled(boolean)

lookup

public final <TLookup> TLookup lookup(Class<TLookup> type)

Description copied from interface: ILookup

Returns an instance that implements the given type or null. Typically, this method will be called in order 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 reobtained for subsequent use.

Specified by:

lookup in interface ILookup

Parameters:

type - the type for which an instance shall be returned

Returns:

an instance that is assignable to type or null

setAngle

public final void setAngle(double value)

Sets the rotation angle of all labels with this model in radians.

Parameters:

value - The rotation angle of all labels with this model in radians.

See Also:

getAngle()

setAutoRotationEnabled

public final void setAutoRotationEnabled(boolean value)

Sets whether edge labels are automatically rotated according to the angle of the corresponding reference edge segment.

By default, this feature is enabled.

Parameters:

value - true if edge labels are automatically rotated; false otherwise.

See Also:

isAutoRotationEnabled()

setDistance

public final void setDistance(double value)

Sets the distance between the label box and the edge path.

The interpretation of the values depends on the SideOfEdge of the individual ILabelModelParameter.

Note that for EdgeSides.ON_EDGE this property is ignored. For all other values of EdgeSides the Offset property is added to this distance.

Parameters:

value - The distance between the label box and the edge path.

See Also:

getSideOfEdge(), EdgeSides, getOffset(), getDistance()

setOffset

public final void setOffset(double value)

Sets the offset of the label box and the edge path relative to the default placement.

For EdgeSides.ON_EDGE this is the offset between the center of the label box and the edge path. For all other EdgeSides values this offset is added to the Distance property which results in the total distance between the label box and the edge path.

Parameters:

value - The offset of the label box and the edge path relative to the default placement.

See Also:

getSideOfEdge(), EdgeSides, getOffset()

setSideOfEdge

public final void setSideOfEdge(EdgeSides value)

Sets the side placement specifiers for edge labels.

The label model parameter finder and provider returned by lookup(Class) consider the specified sides.

Parameters:

value - The SideOfEdge to set.

See Also:

EdgeSides, getSideOfEdge()