com.yworks.yfiles.view.input

Class LabelPositionHandler

java.lang.Object

com.yworks.yfiles.view.input.LabelPositionHandler

All Implemented Interfaces:

IDragHandler, IPositionHandler

public class LabelPositionHandler
extends Object
implements IPositionHandler

An implementation of IPositionHandler that shows the various label position candidates and lets the user move a label to one of those candidate positions.

Field Summary

Fields

Modifier and Type	Field and Description
static ResourceKey	CANDIDATE_TEMPLATE_KEY A ResourceKey that will be used to find the IVisualTemplate that will be used to represent the rectangular selection.
static ResourceKey	HIGHLIGHT_TEMPLATE_KEY A ResourceKey that will be used to find the IVisualTemplate that will be used to represent the rectangular selection.

Constructor Summary

Constructors

Constructor and Description
LabelPositionHandler(ILabel label) Initializes a new instance of the LabelPositionHandler class.

Method Summary

Modifier and Type	Method and Description
void	cancelDrag(IInputModeContext context, PointD originalLocation) Called by clients to indicate that the dragging has been canceled by the user.
protected ICanvasObjectDescriptor	createCandidateDescriptor(IInputModeContext context, boolean highlight) Creates an ICanvasObjectDescriptor to display the given candidate position.
void	dragFinished(IInputModeContext context, PointD originalLocation, PointD newLocation) Called by clients to indicate that the repositioning has just been finished.
IVisualTemplate	getCandidateTemplate() Gets the template to use for showing candidates.
protected double	getDistance(IOrientedRectangle rectangle, PointD location) Calculates a distance value between a candidate rectangle and the mouse location.
protected IGraph	getGraph() Gets the graph instance from the IInputModeContext that has been passed to the initializeDrag(IInputModeContext) method.
IVisualTemplate	getHighlightTemplate() Gets the template to use for showing highlighted candidates.
protected ILabel	getLabel() Gets the label instance.
IPoint	getLocation() Returns a view of the location of the item.
protected Iterable<ILabelModelParameter>	getParameterCandidates(ILabel label) Callback method that gets the candidates for the given label.
void	handleMove(IInputModeContext context, PointD originalLocation, PointD newLocation) Called by clients to indicate that the element has been dragged and its position should be updated.
void	initializeDrag(IInputModeContext context) Called by clients to indicate that the element is going to be dragged.
boolean	isUsingFinderEnabled() Gets a property that determines whether the handler may use a ILabelModelParameterFinder to assign arbitrary positions.
void	setCandidateTemplate(IVisualTemplate value) Sets the template to use for showing candidates.
void	setHighlightTemplate(IVisualTemplate value) Sets the template to use for showing highlighted candidates.
protected void	setLayoutParameter(ILabel label, ILabelModelParameter layoutParameter) Actually applies the given parameter at the end of the gesture.
void	setPosition(PointD location)
void	setUsingFinderEnabled(boolean value) Sets a property that determines whether the handler may use a ILabelModelParameterFinder to assign arbitrary positions.
protected boolean	useParameterFinder(IInputModeContext context) Determines whether to use a ILabelModelParameterFinder to find the best candidate.

Methods inherited from class java.lang.Object

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

Field Detail

CANDIDATE_TEMPLATE_KEY

public static final ResourceKey CANDIDATE_TEMPLATE_KEY

A ResourceKey that will be used to find the IVisualTemplate that will be used to represent the rectangular selection.

HIGHLIGHT_TEMPLATE_KEY

public static final ResourceKey HIGHLIGHT_TEMPLATE_KEY

A ResourceKey that will be used to find the IVisualTemplate that will be used to represent the rectangular selection.

Constructor Detail

LabelPositionHandler

public LabelPositionHandler(ILabel label)

Initializes a new instance of the LabelPositionHandler class.

Parameters:

label - The label that shall be moved.

Method Detail

cancelDrag

public void cancelDrag(IInputModeContext context,
                       PointD originalLocation)

Description copied from interface: IDragHandler

Called by clients to indicate that the dragging has been canceled by the user.

This method may be called after the initial IDragHandler.initializeDrag(IInputModeContext) and zero or more invocations of IDragHandler.handleMove(IInputModeContext, PointD, PointD). Implementations should reset the position of the items they modify to their initial state. Alternatively to this method the IDragHandler.dragFinished(IInputModeContext, PointD, PointD) method might be called.

Specified by:

cancelDrag in interface IDragHandler

Parameters:

context - The context to retrieve information about the drag from.

originalLocation - The value of the coordinate of the Location property at the time of IDragHandler.initializeDrag(IInputModeContext).

createCandidateDescriptor

protected ICanvasObjectDescriptor createCandidateDescriptor(IInputModeContext context,
                                                            boolean highlight)

Creates an ICanvasObjectDescriptor to display the given candidate position.

Parameters:

context - The context for which the descriptor is created.

highlight - Whether to highlight the paintable. This will be true for the current position and false for the others.

Returns:

An implementation that will render the given candidate.

dragFinished

public void dragFinished(IInputModeContext context,
                         PointD originalLocation,
                         PointD newLocation)

Description copied from interface: IDragHandler

Called by clients to indicate that the repositioning has just been finished.

This method may be called after the initial IDragHandler.initializeDrag(IInputModeContext) and zero or more invocations of IDragHandler.handleMove(IInputModeContext, PointD, PointD). Alternatively to this method the IDragHandler.cancelDrag(IInputModeContext, PointD) method might be called.

Specified by:

dragFinished in interface IDragHandler

Parameters:

context - The context to retrieve information about the drag from.

originalLocation - The value of the Location property at the time of IDragHandler.initializeDrag(IInputModeContext).

newLocation - The coordinates in the world coordinate system that the client wants the handle to be at. Depending on the implementation the Location may or may not be modified to reflect the new value. This is the same value as delivered in the last invocation of IDragHandler.handleMove(IInputModeContext, PointD, PointD)

getCandidateTemplate

public final IVisualTemplate getCandidateTemplate()

Gets the template to use for showing candidates.

Returns:

The CandidateTemplate.

See Also:

setCandidateTemplate(IVisualTemplate)

getDistance

protected double getDistance(IOrientedRectangle rectangle,
                             PointD location)

Calculates a distance value between a candidate rectangle and the mouse location.

Parameters:

rectangle - The rectangle candidate.

location - The mouse location.

Returns:

A value indicating the closeness of the mouse to the rectangle.

getGraph

protected final IGraph getGraph()

Gets the graph instance from the IInputModeContext that has been passed to the initializeDrag(IInputModeContext) method.

Returns:

The Graph.

getHighlightTemplate

public final IVisualTemplate getHighlightTemplate()

Gets the template to use for showing highlighted candidates.

Returns:

The HighlightTemplate.

See Also:

setHighlightTemplate(IVisualTemplate)

getLabel

protected final ILabel getLabel()

Gets the label instance.

Returns:

The label.

getLocation

public final IPoint getLocation()

Description copied from interface: IDragHandler

Returns a view of the location of the item.

The point describes the current world coordinate of the element that can be modified by this handler.

Specified by:

getLocation in interface IDragHandler

Returns:

The Location.

getParameterCandidates

protected Iterable<ILabelModelParameter> getParameterCandidates(ILabel label)

Callback method that gets the candidates for the given label.

Parameters:

label - The label.

Returns:

A possibly empty enumerator over possible label parameter candidates.

handleMove

public void handleMove(IInputModeContext context,
                       PointD originalLocation,
                       PointD newLocation)

Description copied from interface: IDragHandler

Called by clients to indicate that the element has been dragged and its position should be updated.

This method may be called more than once after an initial IDragHandler.initializeDrag(IInputModeContext) and will the final call will be followed by either one IDragHandler.dragFinished(IInputModeContext, PointD, PointD) or one IDragHandler.cancelDrag(IInputModeContext, PointD) call.

Specified by:

handleMove in interface IDragHandler

Parameters:

context - The context to retrieve information about the drag from.

originalLocation - The value of the Location property at the time of IDragHandler.initializeDrag(IInputModeContext).

newLocation - The coordinates in the world coordinate system that the client wants the handle to be at. Depending on the implementation the Location may or may not be modified to reflect the new value.

initializeDrag

public void initializeDrag(IInputModeContext context)

Description copied from interface: IDragHandler

Called by clients to indicate that the element is going to be dragged.

This call will be followed by one or more calls to IDragHandler.handleMove(IInputModeContext, PointD, PointD), and a final IDragHandler.dragFinished(IInputModeContext, PointD, PointD) or IDragHandler.cancelDrag(IInputModeContext, PointD).

Specified by:

initializeDrag in interface IDragHandler

Parameters:

context - The context to retrieve information about the drag from.

isUsingFinderEnabled

public final boolean isUsingFinderEnabled()

Gets a property that determines whether the handler may use a ILabelModelParameterFinder to assign arbitrary positions.

The default value is true

Returns:

The UsingFinderEnabled.

See Also:

useParameterFinder(IInputModeContext), setUsingFinderEnabled(boolean)

setCandidateTemplate

public final void setCandidateTemplate(IVisualTemplate value)

Sets the template to use for showing candidates.

Parameters:

value - The CandidateTemplate to set.

See Also:

getCandidateTemplate()

setHighlightTemplate

public final void setHighlightTemplate(IVisualTemplate value)

Sets the template to use for showing highlighted candidates.

Parameters:

value - The HighlightTemplate to set.

See Also:

getHighlightTemplate()

setLayoutParameter

protected void setLayoutParameter(ILabel label,
                                  ILabelModelParameter layoutParameter)

Actually applies the given parameter at the end of the gesture.

Parameters:

label - The label to set the parameter for.

layoutParameter - The new parameter.

setPosition

public void setPosition(PointD location)

setUsingFinderEnabled

public final void setUsingFinderEnabled(boolean value)

Sets a property that determines whether the handler may use a ILabelModelParameterFinder to assign arbitrary positions.

The default value is true

Parameters:

value - The UsingFinderEnabled to set.

See Also:

useParameterFinder(IInputModeContext), isUsingFinderEnabled()

useParameterFinder

protected boolean useParameterFinder(IInputModeContext context)

Determines whether to use a ILabelModelParameterFinder to find the best candidate.

This implementation returns true if the UsingFinderEnabled property is true and the control key is pressed.

Parameters:

context - The context that is currently being used - may be null if the method is called without context.