Package org.eclipse.gef.fx.anchors

Class AbstractAnchor

java.lang.Object

org.eclipse.gef.fx.anchors.AbstractAnchor

All Implemented Interfaces:

IAnchor

Direct Known Subclasses:

DynamicAnchor, StaticAnchor

public abstract class AbstractAnchor
extends Object
implements IAnchor

AbstractAnchor is the abstract base implementation for IAnchors. It provides the facility to bind an anchor to an anchorage Node (anchorageProperty()), to attach and detach Nodes via AnchorKeys, and to provide positions ( positionsUnmodifiableProperty()) for the attached AnchorKey s.

It also registers the necessary listeners at the anchorage Node and the attached Nodes as well as relevant ancestor Nodes, to trigger the (re-)computation of positions.

The actual computation of positions for attached nodes is delegated to computePosition(AnchorKey), thus left to subclasses. If a subclass needs additional information to compute positions for attached AnchorKeys, it may request that an IAdaptable info gets passed into attach(AnchorKey) and detach(AnchorKey), and may overwrite both methods to get access to it.

Property Summary

Properties

Type	Property	Description
ReadOnlyObjectProperty<Node>	anchorage	Provides a read-only property with the anchorage Node this IAnchor is bound to.
ReadOnlyMapProperty<AnchorKey,Point>	positionsUnmodifiable	Provides a read-only (map) property with positions (in local coordinates of the anchored Nodes) for all attached AnchorKeys.

Constructor Summary

Constructors

Constructor	Description
AbstractAnchor(Node anchorage)	Creates a new AbstractAnchor for the given anchorage Node.

Method Summary

Modifier and Type	Method	Description
ReadOnlyObjectProperty<Node>	anchorageProperty()	Provides a read-only property with the anchorage Node this IAnchor is bound to.
void	attach(AnchorKey key)	Attaches the given AnchorKey to this IAnchor.
protected abstract Point	computePosition(AnchorKey key)	Recomputes the position for the given attached AnchorKey by delegating to the respective IComputationStrategy.
void	detach(AnchorKey key)	Detaches the given AnchorKey from this IAnchor.
Node	getAnchorage()	Gets the value of the property anchorage.
protected Set<AnchorKey>	getKeys()	Returns all keys maintained by this anchor.
protected SetMultimap<Node,AnchorKey>	getKeysByNode()	Returns the Map which stores the registered AnchorKeys per Node by reference.
Point	getPosition(AnchorKey key)	Provides a position for the given AnchorKey.
ObservableMap<AnchorKey,Point>	getPositionsUnmodifiable()	Gets the value of the property positionsUnmodifiable.
boolean	isAttached(AnchorKey key)	Determines if the given AnchorKey is currently attached to this IAnchor.
ReadOnlyMapProperty<AnchorKey,Point>	positionsUnmodifiableProperty()	Provides a read-only (map) property with positions (in local coordinates of the anchored Nodes) for all attached AnchorKeys.
protected void	registerVCL(Node anchored)	Registers a VisualChangeListener for the given anchored Node.
protected void	registerVCLs()	Registers VisualChangeListeners for all anchored Nodes, or schedules their registration if the VCL cannot be registered yet.
protected void	setAnchorage(Node anchorage)	Sets the anchorage of this AbstractAnchor to the given value.
protected void	unregisterVCL(Node anchored)	Unregisters the VisualChangeListeners for the given anchored Node.
protected void	unregisterVCLs()	Unregisters the VisualChangeListeners for all anchored Nodes.
protected void	updatePosition(AnchorKey key)	Updates the position for the given AnchorKey, i.e.
protected void	updatePositions()	Updates the positions for all attached AnchorKeys.

Methods inherited from class java.lang.Object

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

Property Details

anchorage

public ReadOnlyObjectProperty<Node> anchorageProperty

Specified by:

anchorageProperty in interface IAnchor

Returns:

A read-only property storing the anchorage Node.

See Also:

• getAnchorage()
• setAnchorage(Node)

positionsUnmodifiable

public ReadOnlyMapProperty<AnchorKey,Point> positionsUnmodifiableProperty

Specified by:

positionsUnmodifiableProperty in interface IAnchor

Returns:

A read-only (map) property storing positions for all attached AnchorKeys.

See Also:

• getPositionsUnmodifiable()

Constructor Details

AbstractAnchor

public AbstractAnchor(Node anchorage)

Creates a new AbstractAnchor for the given anchorage Node.

Parameters:

anchorage - The anchorage Node for this AbstractAnchor.

Method Details

anchorageProperty

public ReadOnlyObjectProperty<Node> anchorageProperty()

Description copied from interface: IAnchor

Provides a read-only property with the anchorage Node this IAnchor is bound to. The property value may be null in case this IAnchor is not bound to an anchorage Node.

Specified by:

anchorageProperty in interface IAnchor

Returns:

A read-only property storing the anchorage Node.

See Also:

• getAnchorage()
• setAnchorage(Node)

attach

public void attach(AnchorKey key)

Description copied from interface: IAnchor

Attaches the given AnchorKey to this IAnchor.

Specified by:

attach in interface IAnchor

Parameters:

key - The AnchorKey to be attached.

computePosition

protected abstract Point computePosition(AnchorKey key)

Recomputes the position for the given attached AnchorKey by delegating to the respective IComputationStrategy.

Parameters:

key - The AnchorKey for which to compute an anchor position.

Returns:

The point for the given AnchorKey in local coordinates of the anchored Node.

detach

public void detach(AnchorKey key)

Description copied from interface: IAnchor

Detaches the given AnchorKey from this IAnchor.

Specified by:

detach in interface IAnchor

Parameters:

key - The AnchorKey to be detached.

getAnchorage

public Node getAnchorage()

Gets the value of the property anchorage.

Specified by:

getAnchorage in interface IAnchor

Property description:

Returns:

The value of the IAnchor.anchorageProperty().

getKeys

protected Set<AnchorKey> getKeys()

Returns all keys maintained by this anchor.

Returns:

A set containing all AnchorKeys.

getKeysByNode

protected SetMultimap<Node,AnchorKey> getKeysByNode()

Returns the Map which stores the registered AnchorKeys per Node by reference.

Returns:

The Map which stores the registered AnchorKeys per Node by reference.

getPosition

public Point getPosition(AnchorKey key)

Description copied from interface: IAnchor

Provides a position for the given AnchorKey. The provided AnchorKey has to be attached to this IAnchor (see IAnchor.attach(AnchorKey)).

Specified by:

getPosition in interface IAnchor

Parameters:

key - The AnchorKey to retrieve a position for. It has to be attached (IAnchor.attach(AnchorKey)) to this IAnchor before.

Returns:

The position for the given AnchorKey within local coordinates of the AnchorKey's anchored Node.

getPositionsUnmodifiable

public ObservableMap<AnchorKey,Point> getPositionsUnmodifiable()

Gets the value of the property positionsUnmodifiable.

Specified by:

getPositionsUnmodifiable in interface IAnchor

Property description:

Returns:

A read-only observable map storing positions for all attached AnchorKeys.

isAttached

public boolean isAttached(AnchorKey key)

Description copied from interface: IAnchor

Determines if the given AnchorKey is currently attached to this IAnchor.

Specified by:

isAttached in interface IAnchor

Parameters:

key - The AnchorKey to test.

Returns:

true if the given key is attached, otherwise false.

positionsUnmodifiableProperty

public ReadOnlyMapProperty<AnchorKey,Point> positionsUnmodifiableProperty()

Description copied from interface: IAnchor

Provides a read-only (map) property with positions (in local coordinates of the anchored Nodes) for all attached AnchorKeys. The positions will be updated for all attached AnchorKeys if the attached Nodes or the anchorage Node, the IAnchor is bound to, or any of their ancestors changes in a way that will effect the positions (within the local coordinate space of the attached Nodes).

Specified by:

positionsUnmodifiableProperty in interface IAnchor

Returns:

A read-only (map) property storing positions for all attached AnchorKeys.

See Also:

• getPositionsUnmodifiable()

registerVCL

protected void registerVCL(Node anchored)

Registers a VisualChangeListener for the given anchored Node.

Parameters:

anchored - The anchored Node to register a VisualChangeListener at.

registerVCLs

protected void registerVCLs()

Registers VisualChangeListeners for all anchored Nodes, or schedules their registration if the VCL cannot be registered yet.

setAnchorage

protected void setAnchorage(Node anchorage)

Sets the anchorage of this AbstractAnchor to the given value.

Parameters:

anchorage - The new anchorage for this AbstractAnchor.

unregisterVCL

protected void unregisterVCL(Node anchored)

Unregisters the VisualChangeListeners for the given anchored Node.

Parameters:

anchored - The anchored Node to unregister a VisualChangeListener from.

unregisterVCLs

protected void unregisterVCLs()

Unregisters the VisualChangeListeners for all anchored Nodes.

updatePosition

protected void updatePosition(AnchorKey key)

Updates the position for the given AnchorKey, i.e.

1. Queries its current position.
2. Computes its new position.
3. Checks if the position changed, and fires an appropriate event by putting the new position into the positionsUnmodifiableProperty()

Parameters:

key - The AnchorKey for which the position is updated.

updatePositions

protected void updatePositions()

Updates the positions for all attached AnchorKeys.