com.yworks.yfiles.view.input

Class LabelSnapContext

java.lang.Object

com.yworks.yfiles.view.input.SnapContext

com.yworks.yfiles.view.input.LabelSnapContext

public class LabelSnapContext
extends SnapContext

Manages interactive snapping of ILabels to their owner during drag operations like movements.

This class provides a set of properties to customize the snapping behavior. IPositionHandler implementations and similar classes can use the following idiom to get an instance of this class:

See Also:

MoveLabelInputMode, GraphEditorInputMode.getSnapContext()

Constructor Summary

Constructors

Constructor and Description
LabelSnapContext() Initializes a new instance of the LabelSnapContext class.

Method Summary

Modifier and Type	Method and Description
void	addCollectSnapLinesListener(IEventHandler<CollectLabelSnapLineEventArgs> collectSnapLinesEvent) Adds the given listener for the CollectSnapLines event that occurs every time this instance has been initialized to collect SnapLines.
void	addSnapLine(SnapLine snapLine) Adds the given snapLine to the snap line collection of this context.
protected void	cleanUp() Performs clean up procedures.
SnapState	dragFinished(PointD newLocation, boolean snappingDisabled) Called when a drag has been successfully finished.
void	dragInitialized() Collects a list of snap lines.
double	getSnapLineExtension() Gets the amount by which snap lines that are induced by existing edge segments are being extended.
IEnumerable<SnapLine>	getSnapLines() The collection of the snap lines that have been added to this context.
SnapState	handleMove(PointD newLocation, boolean snappingDisabled) Handles a move.
void	initializeDrag(IInputModeContext context, PointD originalLocation) Called by IInputMode implementations when an interactive drag is started.
boolean	isCollectingAllEdgeDistanceSnapLinesEnabled() Determines whether this instance should collect snap lines in parallel to the edge path of the label owner at the distance of other edge labels in the graph.
boolean	isCollectingAllNodeDistanceSnapLinesEnabled() Determines whether this instance should collect snap lines in parallel to the border of the label owner at the distance of other node labels in the graph.
boolean	isCollectingEdgePathSnapLinesEnabled() Determines whether this instance should collect snap lines on the edge path.
boolean	isCollectingInitialLocationSnapLinesEnabled() Determines whether this instance should collect snap lines for the initial position of a label.
boolean	isCollectingNodeShapeSnapLinesEnabled() Determines whether this instance should collect six snap lines, two through the center and four through the border sides of the label owner.
boolean	isCollectingOwnEdgeDistanceSnapLinesEnabled() Determines whether this instance should collect two snap lines in parallel to the edge path of the label owner at the initial distance of the edge label.
boolean	isCollectingOwnNodeDistanceSnapLinesEnabled() Determines whether this instance should collect four snap lines in parallel to the owner's borders at the initial label distance.
boolean	isCollectingSameOwnerEdgeDistanceSnapLinesEnabled() Determines whether this instance should collect snap lines in parallel to the edge path of the label owner at the distances of all edge labels of that owner.
boolean	isCollectingSameOwnerNodeDistanceSnapLinesEnabled() Determines whether this instance should collect snap lines in parallel to the border of the label owner at the distance of other node labels of that owner.
boolean	isSnappingEdgeLabelsEnabled() Specifies whether this context will automatically snap the edge labels to snap lines.
boolean	isSnappingNodeLabelsEnabled() Specifies whether this context will automatically snap the node labels to snap lines.
protected void	onCollectSnapLines(CollectLabelSnapLineEventArgs args) Raises the CollectSnapLines event.
void	removeCollectSnapLinesListener(IEventHandler<CollectLabelSnapLineEventArgs> collectSnapLinesEvent) Removes the given listener for the CollectSnapLines event that occurs every time this instance has been initialized to collect SnapLines.
void	setCollectingAllEdgeDistanceSnapLinesEnabled(boolean value) Determines whether this instance should collect snap lines in parallel to the edge path of the label owner at the distance of other edge labels in the graph.
void	setCollectingAllNodeDistanceSnapLinesEnabled(boolean value) Determines whether this instance should collect snap lines in parallel to the border of the label owner at the distance of other node labels in the graph.
void	setCollectingEdgePathSnapLinesEnabled(boolean value) Determines whether this instance should collect snap lines on the edge path.
void	setCollectingInitialLocationSnapLinesEnabled(boolean value) Determines whether this instance should collect snap lines for the initial position of a label.
void	setCollectingNodeShapeSnapLinesEnabled(boolean value) Determines whether this instance should collect six snap lines, two through the center and four through the border sides of the label owner.
void	setCollectingOwnEdgeDistanceSnapLinesEnabled(boolean value) Determines whether this instance should collect two snap lines in parallel to the edge path of the label owner at the initial distance of the edge label.
void	setCollectingOwnNodeDistanceSnapLinesEnabled(boolean value) Determines whether this instance should collect four snap lines in parallel to the owner's borders at the initial label distance.
void	setCollectingSameOwnerEdgeDistanceSnapLinesEnabled(boolean value) Determines whether this instance should collect snap lines in parallel to the edge path of the label owner at the distances of all edge labels of that owner.
void	setCollectingSameOwnerNodeDistanceSnapLinesEnabled(boolean value) Determines whether this instance should collect snap lines in parallel to the border of the label owner at the distance of other node labels of that owner.
void	setSnapLineExtension(double value) Sets the amount by which snap lines that are induced by existing edge segments are being extended.
void	setSnappingEdgeLabelsEnabled(boolean value) Specifies whether this context will automatically snap the edge labels to snap lines.
void	setSnappingNodeLabelsEnabled(boolean value) Specifies whether this context will automatically snap the node labels to snap lines.
IInputModeContext	wrapContext(IInputModeContext context) Helper method that wraps the given context so that a ILookup.lookup(Class) query on the wrapped context for the SnapContext type yields this instance.

Methods inherited from class com.yworks.yfiles.view.input.SnapContext

addCleanedUpListener, addCollectSnapResultsListener, addInitializedListener, addInitializingListener, cancelDrag, createSnapResultCanvasObjectDescriptor, createSnapResultsModelManager, dragged, getCurrentInputModeContext, getOriginalLocation, getSnapDistance, getSnapResults, isEnabled, isInitialized, isInitializing, isSnapResultVisualizationEnabled, onCleanUp, onCollectSnapResults, onInitialized, onInitializing, processSnapResults, removeCleanedUpListener, removeCollectSnapResultsListener, removeInitializedListener, removeInitializingListener, setEnabled, setSnapDistance, setSnapResultVisualizationEnabled

Methods inherited from class java.lang.Object

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

Constructor Detail

LabelSnapContext

public LabelSnapContext()

Initializes a new instance of the LabelSnapContext class.

Method Detail

addCollectSnapLinesListener

public final void addCollectSnapLinesListener(IEventHandler<CollectLabelSnapLineEventArgs> collectSnapLinesEvent)

Adds the given listener for the CollectSnapLines event that occurs every time this instance has been initialized to collect SnapLines.

Event handlers should add snap lines to the caller using the methods provided by CollectLabelSnapLineEventArgs.

Parameters:

collectSnapLinesEvent - The listener to add.

See Also:

removeCollectSnapLinesListener(IEventHandler)

addSnapLine

public final void addSnapLine(SnapLine snapLine)

Adds the given snapLine to the snap line collection of this context.

Parameters:

snapLine - The snap line to add.

See Also:

GraphSnapContext.getAdditionalSnapLines()

cleanUp

protected void cleanUp()

Description copied from class: SnapContext

Performs clean up procedures.

This is called in response to SnapContext.cancelDrag() and SnapContext.dragFinished(PointD, boolean) as well as initially during SnapContext.initializeDrag(IInputModeContext, PointD).

Overrides:

cleanUp in class SnapContext

dragFinished

public SnapState dragFinished(PointD newLocation,
                              boolean snappingDisabled)

Description copied from class: SnapContext

Called when a drag has been successfully finished.

Clears all temporary lists and sets IsInitialized back to false. Also the SnapContext.cleanUp() method is invoked and the CleanedUp event is triggered.

Overrides:

dragFinished in class SnapContext

Parameters:

newLocation - The current mouse location.

snappingDisabled - If set to true snapping is temporarily disabled. This will remove the snap line visualizations and return a SnapState with the unchanged coordinates and the SnapTypes.NOT_SNAPPED SnapType.

Returns:

A SnapState that specifies the adjusted coordinates and how they have been adjusted. The unchanged coordinates if snapping has been temporarily disabled by setting snappingDisabled to true.

dragInitialized

public void dragInitialized()

Description copied from class: SnapContext

Collects a list of snap lines.

Snap lines represent possible horizontal or vertical lines to which a moved item can "snap".

This method is called at the start of MoveInputMode's or HandleInputMode's gesture after all items to be moved or reshaped have been added.

Overrides:

dragInitialized in class SnapContext

getSnapLineExtension

public final double getSnapLineExtension()

Gets the amount by which snap lines that are induced by existing edge segments are being extended.

The default is 40.0d, this value will be used to prolongate the ends of the snap lines.

Returns:

The amount by which snap lines that are induced by existing edge segments are being extended.

See Also:

setSnapLineExtension(double)

getSnapLines

public final IEnumerable<SnapLine> getSnapLines()

The collection of the snap lines that have been added to this context.

This collection is only available if IsInitialized is true.

Returns:

The SnapLines.

See Also:

addSnapLine(SnapLine)

handleMove

public SnapState handleMove(PointD newLocation,
                            boolean snappingDisabled)

Description copied from class: SnapContext

Handles a move.

This method returns the adjusted (mouse) coordinates. It also manages the collection of SnapResults. If snapping should be temporarily (for a mouse move) disabled, snappingDisabled has to be set to true.

Overrides:

handleMove in class SnapContext

Parameters:

newLocation - The current mouse location.

snappingDisabled - If set to true snapping is temporarily disabled. This will remove the snap line visualizations and return a SnapState with the unchanged coordinates and the SnapType SnapTypes.NOT_SNAPPED.

Returns:

The adjusted coordinates and how they have been adjusted. The unchanged coordinates if snapping has been temporarily disabled by setting snappingDisabled to true.

initializeDrag

public void initializeDrag(IInputModeContext context,
                           PointD originalLocation)

Description copied from class: SnapContext

Called by IInputMode implementations when an interactive drag is started.

Updates IsInitializing, OriginalLocation, and CurrentInputModeContext and then triggers the Initializing event.

Overrides:

initializeDrag in class SnapContext

Parameters:

context - The context in which the interactive drag is started.

originalLocation - The original location of the mouse.

isCollectingAllEdgeDistanceSnapLinesEnabled

public final boolean isCollectingAllEdgeDistanceSnapLinesEnabled()

Determines whether this instance should collect snap lines in parallel to the edge path of the label owner at the distance of other edge labels in the graph.

The default is false.

Returns:

true if this instance should collect this kind of snap lines; false otherwise.

See Also:

setCollectingAllEdgeDistanceSnapLinesEnabled(boolean)

isCollectingAllNodeDistanceSnapLinesEnabled

public final boolean isCollectingAllNodeDistanceSnapLinesEnabled()

Determines whether this instance should collect snap lines in parallel to the border of the label owner at the distance of other node labels in the graph.

Note that the label snaps to these snap lines with the side that is closer to the node's border. That way, snapping to such a snap line preserves the perceived distance from the node border for both labels inside and outside the node bounds.

The default is false.

Returns:

true if this instance should collect this kind of snap lines; false otherwise.

See Also:

setCollectingAllNodeDistanceSnapLinesEnabled(boolean)

isCollectingEdgePathSnapLinesEnabled

public final boolean isCollectingEdgePathSnapLinesEnabled()

Determines whether this instance should collect snap lines on the edge path.

The default is true.

Returns:

true if this instance should collect this kind of snap lines; false otherwise.

See Also:

setCollectingEdgePathSnapLinesEnabled(boolean)

isCollectingInitialLocationSnapLinesEnabled

public final boolean isCollectingInitialLocationSnapLinesEnabled()

Determines whether this instance should collect snap lines for the initial position of a label.

The default is true.

Returns:

true if this instance should collect snap lines for the initial position of a label; false otherwise.

See Also:

setCollectingInitialLocationSnapLinesEnabled(boolean)

isCollectingNodeShapeSnapLinesEnabled

public final boolean isCollectingNodeShapeSnapLinesEnabled()

Determines whether this instance should collect six snap lines, two through the center and four through the border sides of the label owner.

The default is true.

Returns:

true if this instance should collect snap lines through the border and center of the label owner; otherwise, false.

See Also:

setCollectingNodeShapeSnapLinesEnabled(boolean)

isCollectingOwnEdgeDistanceSnapLinesEnabled

public final boolean isCollectingOwnEdgeDistanceSnapLinesEnabled()

Determines whether this instance should collect two snap lines in parallel to the edge path of the label owner at the initial distance of the edge label.

The default is true.

Returns:

true if this instance should collect this kind of snap lines; false otherwise.

See Also:

setCollectingOwnEdgeDistanceSnapLinesEnabled(boolean)

isCollectingOwnNodeDistanceSnapLinesEnabled

public final boolean isCollectingOwnNodeDistanceSnapLinesEnabled()

Determines whether this instance should collect four snap lines in parallel to the owner's borders at the initial label distance.

Note that the label snaps to these snap lines with the side that is closer to the node's border. That way, snapping to such a snap line preserves the perceived distance from the node border for both labels inside and outside the node bounds.

The default is true.

Returns:

true if this instance should collect snap lines through the border and center of the label owner; otherwise, false.

See Also:

setCollectingOwnNodeDistanceSnapLinesEnabled(boolean)

isCollectingSameOwnerEdgeDistanceSnapLinesEnabled

public final boolean isCollectingSameOwnerEdgeDistanceSnapLinesEnabled()

Determines whether this instance should collect snap lines in parallel to the edge path of the label owner at the distances of all edge labels of that owner.

The default is true.

Returns:

true if this instance should collect this kind of snap lines; false otherwise.

See Also:

setCollectingSameOwnerEdgeDistanceSnapLinesEnabled(boolean)

isCollectingSameOwnerNodeDistanceSnapLinesEnabled

public final boolean isCollectingSameOwnerNodeDistanceSnapLinesEnabled()

Determines whether this instance should collect snap lines in parallel to the border of the label owner at the distance of other node labels of that owner.

Note that the label snaps to these snap lines with the side that is closer to the node's border. That way, snapping to such a snap line preserves the perceived distance from the node border for both labels inside and outside the node bounds.

The default is true.

Returns:

true if this instance should collect this kind of snap lines; false otherwise.

See Also:

setCollectingSameOwnerNodeDistanceSnapLinesEnabled(boolean)

isSnappingEdgeLabelsEnabled

public final boolean isSnappingEdgeLabelsEnabled()

Specifies whether this context will automatically snap the edge labels to snap lines.

The default is true.

Returns:

true if edge labels will snap to snap lines; false otherwise.

See Also:

setSnappingEdgeLabelsEnabled(boolean)

isSnappingNodeLabelsEnabled

public final boolean isSnappingNodeLabelsEnabled()

Specifies whether this context will automatically snap the node labels to snap lines.

The default is true.

Returns:

true if node labels will snap to snap lines; false otherwise.

See Also:

setSnappingNodeLabelsEnabled(boolean)

onCollectSnapLines

protected void onCollectSnapLines(CollectLabelSnapLineEventArgs args)

Raises the CollectSnapLines event.

Parameters:

args - The CollectLabelSnapLineEventArgs instance containing the event data.

removeCollectSnapLinesListener

public final void removeCollectSnapLinesListener(IEventHandler<CollectLabelSnapLineEventArgs> collectSnapLinesEvent)

Removes the given listener for the CollectSnapLines event that occurs every time this instance has been initialized to collect SnapLines.

Event handlers should add snap lines to the caller using the methods provided by CollectLabelSnapLineEventArgs.

Parameters:

collectSnapLinesEvent - The listener to remove.

See Also:

addCollectSnapLinesListener(IEventHandler)

setCollectingAllEdgeDistanceSnapLinesEnabled

public final void setCollectingAllEdgeDistanceSnapLinesEnabled(boolean value)

Determines whether this instance should collect snap lines in parallel to the edge path of the label owner at the distance of other edge labels in the graph.

The default is false.

Parameters:

value - true if this instance should collect this kind of snap lines; false otherwise.

See Also:

isCollectingAllEdgeDistanceSnapLinesEnabled()

setCollectingAllNodeDistanceSnapLinesEnabled

public final void setCollectingAllNodeDistanceSnapLinesEnabled(boolean value)

Determines whether this instance should collect snap lines in parallel to the border of the label owner at the distance of other node labels in the graph.

Note that the label snaps to these snap lines with the side that is closer to the node's border. That way, snapping to such a snap line preserves the perceived distance from the node border for both labels inside and outside the node bounds.

The default is false.

Parameters:

value - true if this instance should collect this kind of snap lines; false otherwise.

See Also:

isCollectingAllNodeDistanceSnapLinesEnabled()

setCollectingEdgePathSnapLinesEnabled

public final void setCollectingEdgePathSnapLinesEnabled(boolean value)

Determines whether this instance should collect snap lines on the edge path.

The default is true.

Parameters:

value - true if this instance should collect this kind of snap lines; false otherwise.

See Also:

isCollectingEdgePathSnapLinesEnabled()

setCollectingInitialLocationSnapLinesEnabled

public final void setCollectingInitialLocationSnapLinesEnabled(boolean value)

Determines whether this instance should collect snap lines for the initial position of a label.

The default is true.

Parameters:

value - true if this instance should collect snap lines for the initial position of a label; false otherwise.

See Also:

isCollectingInitialLocationSnapLinesEnabled()

setCollectingNodeShapeSnapLinesEnabled

public final void setCollectingNodeShapeSnapLinesEnabled(boolean value)

Determines whether this instance should collect six snap lines, two through the center and four through the border sides of the label owner.

The default is true.

Parameters:

value - true if this instance should collect snap lines through the border and center of the label owner; otherwise, false.

See Also:

isCollectingNodeShapeSnapLinesEnabled()

setCollectingOwnEdgeDistanceSnapLinesEnabled

public final void setCollectingOwnEdgeDistanceSnapLinesEnabled(boolean value)

Determines whether this instance should collect two snap lines in parallel to the edge path of the label owner at the initial distance of the edge label.

The default is true.

Parameters:

value - true if this instance should collect this kind of snap lines; false otherwise.

See Also:

isCollectingOwnEdgeDistanceSnapLinesEnabled()

setCollectingOwnNodeDistanceSnapLinesEnabled

public final void setCollectingOwnNodeDistanceSnapLinesEnabled(boolean value)

Determines whether this instance should collect four snap lines in parallel to the owner's borders at the initial label distance.

Note that the label snaps to these snap lines with the side that is closer to the node's border. That way, snapping to such a snap line preserves the perceived distance from the node border for both labels inside and outside the node bounds.

The default is true.

Parameters:

value - true if this instance should collect snap lines through the border and center of the label owner; otherwise, false.

See Also:

isCollectingOwnNodeDistanceSnapLinesEnabled()

setCollectingSameOwnerEdgeDistanceSnapLinesEnabled

public final void setCollectingSameOwnerEdgeDistanceSnapLinesEnabled(boolean value)

Determines whether this instance should collect snap lines in parallel to the edge path of the label owner at the distances of all edge labels of that owner.

The default is true.

Parameters:

value - true if this instance should collect this kind of snap lines; false otherwise.

See Also:

isCollectingSameOwnerEdgeDistanceSnapLinesEnabled()

setCollectingSameOwnerNodeDistanceSnapLinesEnabled

public final void setCollectingSameOwnerNodeDistanceSnapLinesEnabled(boolean value)

Determines whether this instance should collect snap lines in parallel to the border of the label owner at the distance of other node labels of that owner.

Note that the label snaps to these snap lines with the side that is closer to the node's border. That way, snapping to such a snap line preserves the perceived distance from the node border for both labels inside and outside the node bounds.

The default is true.

Parameters:

value - true if this instance should collect this kind of snap lines; false otherwise.

See Also:

isCollectingSameOwnerNodeDistanceSnapLinesEnabled()

setSnapLineExtension

public final void setSnapLineExtension(double value)

Sets the amount by which snap lines that are induced by existing edge segments are being extended.

The default is 40.0d, this value will be used to prolongate the ends of the snap lines.

Parameters:

value - The amount by which snap lines that are induced by existing edge segments are being extended.

See Also:

getSnapLineExtension()

setSnappingEdgeLabelsEnabled

public final void setSnappingEdgeLabelsEnabled(boolean value)

Specifies whether this context will automatically snap the edge labels to snap lines.

The default is true.

Parameters:

value - true if edge labels will snap to snap lines; false otherwise.

See Also:

isSnappingEdgeLabelsEnabled()

setSnappingNodeLabelsEnabled

public final void setSnappingNodeLabelsEnabled(boolean value)

Specifies whether this context will automatically snap the node labels to snap lines.

The default is true.

Parameters:

value - true if node labels will snap to snap lines; false otherwise.

See Also:

isSnappingNodeLabelsEnabled()

wrapContext

public IInputModeContext wrapContext(IInputModeContext context)

Description copied from class: SnapContext

Helper method that wraps the given context so that a ILookup.lookup(Class) query on the wrapped context for the SnapContext type yields this instance.

Overrides:

wrapContext in class SnapContext

Parameters:

context - The context to wrap and delegate all calls to.

Returns:

A modified instance that yields this instance if it is queried for the SnapContext type.