com.yworks.yfiles.graph.styles

Class AbstractLabelStyle

java.lang.Object

com.yworks.yfiles.graph.styles.AbstractLabelStyle

All Implemented Interfaces:

ILabelStyle, ICloneable, Cloneable

public abstract class AbstractLabelStyle
extends Object
implements ILabelStyle, Cloneable

An abstract base class that makes it possible to easily implement a custom ILabelStyle.

Only createVisual(IRenderContext, ILabel) and getPreferredSize(ILabel) need to be implemented by subclasses, however to improve rendering performance it is highly recommended to implement at least updateVisual(IRenderContext, Node, ILabel), too.

This implementation differs from the straightforward ILabelStyle implementation in that there is no visible separation between the style and its ILabelStyleRenderer. Instead the renderer used by the base class is fixed and delegates all calls back to the style instance.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractLabelStyle() Initializes a new instance of the AbstractLabelStyle class.

Method Summary

Modifier and Type	Method and Description
protected void	arrangeByLayout(Node visual, IOrientedRectangle layout, boolean autoFlip) Arranges the given visual for use in a VisualGroup using the provided layout and auto flipping rule.
AbstractLabelStyle	clone() Creates a new object that is a copy of the current instance.
protected abstract Node	createVisual(IRenderContext context, ILabel label) Callback that creates the visual.
protected RectD	getBounds(ICanvasContext context, ILabel label) Gets the bounds of the visual for the label in the given context.
protected abstract SizeD	getPreferredSize(ILabel label) Callback that returns the preferred size of the label.
ILabelStyleRenderer	getRenderer() Gets the renderer implementation for this instance.
protected boolean	isHit(IInputModeContext context, PointD location, ILabel label) Determines whether the visual representation of the label has been hit at the given location.
protected boolean	isInBox(IInputModeContext context, RectD rectangle, ILabel label) Determines whether the visualization for the specified label is included in the marquee selection.
protected boolean	isVisible(ICanvasContext context, RectD rectangle, ILabel label) Determines whether the visualization for the specified label is visible in the context.
protected Object	lookup(ILabel label, Class type) Performs the ILookup.lookup(Class) operation for the ILabelStyleRenderer.getContext(ILabel, ILabelStyle) that has been queried from the Renderer.
protected Node	updateVisual(IRenderContext context, Node oldVisual, ILabel label) Callback that updates the visual previously created by createVisual(IRenderContext, ILabel).

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractLabelStyle

protected AbstractLabelStyle()

Initializes a new instance of the AbstractLabelStyle class.

Method Detail

arrangeByLayout

protected void arrangeByLayout(Node visual,
                               IOrientedRectangle layout,
                               boolean autoFlip)

Arranges the given visual for use in a VisualGroup using the provided layout and auto flipping rule.

Parameters:

visual - The visual to arrange.

layout - The layout to use for arranging.

autoFlip - if set to true auto flipping logic will be applied.

clone

public AbstractLabelStyle clone()

Creates a new object that is a copy of the current instance.

Immutable subclasses should consider returning this.

Specified by:

clone in interface ICloneable

Overrides:

clone in class Object

Returns:

A new object that is a copy of this instance using Object.clone().

See Also:

Object.clone()

createVisual

protected abstract Node createVisual(IRenderContext context,
                                     ILabel label)

Callback that creates the visual.

This method is called in response to a IVisualCreator.createVisual(IRenderContext) call to the instance that has been queried from the Renderer.

Parameters:

context - The render context.

label - The label to which this style instance is assigned.

Returns:

The visual as required by the IVisualCreator.createVisual(IRenderContext) interface.

See Also:

updateVisual(IRenderContext, Node, ILabel)

getBounds

protected RectD getBounds(ICanvasContext context,
                          ILabel label)

Gets the bounds of the visual for the label in the given context.

This method is called in response to a IBoundsProvider.getBounds(ICanvasContext) call to the instance that has been queried from the Renderer.

This implementation simply yields the bounds of the layout of the given label.

Parameters:

context - The canvas context.

label - The label to which this style instance is assigned.

Returns:

The visual bounds of the visual representation.

getPreferredSize

protected abstract SizeD getPreferredSize(ILabel label)

Callback that returns the preferred size of the label.

Parameters:

label - The label to which this style instance is assigned.

Returns:

The preferred size.

getRenderer

public final ILabelStyleRenderer getRenderer()

Gets the renderer implementation for this instance.

The private implementation will delegate all API calls back to this instance.

Specified by:

getRenderer in interface ILabelStyle

Returns:

The Renderer.

isHit

protected boolean isHit(IInputModeContext context,
                        PointD location,
                        ILabel label)

Determines whether the visual representation of the label has been hit at the given location.

This method is called in response to a IHitTestable.isHit(IInputModeContext, PointD) call to the instance that has been queried from the Renderer.

This implementation returns the result of the IOrientedRectangle.hits(PointD, double) method invoked for the layout of the label, the given point and the hit test radius of the canvas context.

Parameters:

context - The input mode context.

location - The point to test.

label - The label to which this style instance is assigned.

Returns:

true if the specified label representation is hit; false otherwise.

isInBox

protected boolean isInBox(IInputModeContext context,
                          RectD rectangle,
                          ILabel label)

Determines whether the visualization for the specified label is included in the marquee selection.

This method is called in response to a IMarqueeTestable.isInBox(IInputModeContext, RectD) call to the instance that has been queried from the Renderer.

This implementation returns the result of the RectD.intersects(IOrientedRectangle, double) method invoked on rectangle for the layout of the label and the context.

Parameters:

context - The input mode context.

rectangle - The marquee selection box.

label - The label to which this style instance is assigned.

Returns:

true if the specified label is visible is selected by the marquee rectangle; false otherwise.

isVisible

protected boolean isVisible(ICanvasContext context,
                            RectD rectangle,
                            ILabel label)

Determines whether the visualization for the specified label is visible in the context.

This method is called in response to a IVisibilityTestable.isVisible(ICanvasContext, RectD) call to the instance that has been queried from the Renderer.

This implementation simply tests whether the bounds intersect the clip.

Parameters:

context - The canvas context.

rectangle - The clipping rectangle.

label - The label to which this style instance is assigned.

Returns:

true if the specified label is visible in the clipping rectangle; false otherwise.

lookup

protected Object lookup(ILabel label,
                        Class type)

Performs the ILookup.lookup(Class) operation for the ILabelStyleRenderer.getContext(ILabel, ILabelStyle) that has been queried from the Renderer.

This implementation yields null for everything but:

• IHitTestable
• IVisualCreator
• IBoundsProvider
• IVisibilityTestable
• IMarqueeTestable
• ILookup

For these interfaces an implementation will be returned that delegates to the methods in this instance.

Parameters:

label - The label to use for the context lookup.

type - The type to query.

Returns:

An implementation of the type or null.

updateVisual

protected Node updateVisual(IRenderContext context,
                            Node oldVisual,
                            ILabel label)

Callback that updates the visual previously created by createVisual(IRenderContext, ILabel).

This method is called in response to a IVisualCreator.updateVisual(IRenderContext, Node) call to the instance that has been queried from the Renderer. This implementation simply delegates to createVisual(IRenderContext, ILabel) so subclasses should override to improve rendering performance.

Parameters:

context - The render context.

oldVisual - The visual that has been created in the call to createVisual(IRenderContext, ILabel).

label - The label to which this style instance is assigned.

Returns:

The visual as required by the IVisualCreator.createVisual(IRenderContext) interface.

See Also:

createVisual(IRenderContext, ILabel)