org.eclipse.gef4.layout

Interface ILayoutContext

All Superinterfaces:

org.eclipse.gef4.common.properties.IPropertyChangeNotifier, org.eclipse.gef4.common.properties.IPropertyStore

All Known Implementing Classes:

AbstractLayoutContext

public interface ILayoutContext
extends org.eclipse.gef4.common.properties.IPropertyStore

Objects implementing ILayoutContext interface are used for exchanging of information between layout algorithms and graphical objects displaying graphs, i.e. an ILayoutContext represents a graph within the layout model.

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	DYNAMIC_LAYOUT_ALGORITHM_PROPERTY An ILayoutContext notifies registered listeners about changes to the dynamic layout algorithm using this property name.
static java.lang.String	STATIC_LAYOUT_ALGORITHM_PROPERTY An ILayoutContext notifies registered listeners about changes to the static layout algorithm using this property name.

Method Summary

Modifier and Type	Method and Description
void	addContextListener(IContextListener listener) Adds a listener to the context that will be notified about changes related to its configuration.
void	addGraphStructureListener(IGraphStructureListener listener) Adds a listener to the context that will be notified about changes in graph structure, that is addition and removal of nodes and connections.
void	addLayoutFilter(ILayoutFilter layoutFilter) Adds the given ILayoutFilter to this ILayoutContext.
void	addLayoutListener(ILayoutListener listener) Adds a listener to the context that will be notified about changes in this context's layout, that is movement and resizing of nodes / subgraphs.
void	addPruningListener(IPruningListener listener) Adds a listener to the context that will be notified about changes in graph pruning, that is hiding and showing of nodes.
void	applyDynamicLayout(boolean clean) Applies the background layout algorithm of this LayoutContext.
void	applyStaticLayout(boolean clean) Applies the static layout algorithm of this LayoutContext.
ISubgraphLayout	createSubgraph(INodeLayout[] nodes) Creates a subgraph containing given nodes and adds it to this context.
void	fireBackgroundEnableChangedEvent() Notifies all previously registered IContextListeners about the state of the background layout flag.
void	fireBoundsChangedEvent() Notifies all previously registered IContextListeners about the bounds change.
void	fireConnectionAddedEvent(IConnectionLayout connection) Notifies all previously registered IGraphStructureListeners about the newly added connection.
void	fireConnectionRemovedEvent(IConnectionLayout connection) Notifies all previously registered IGraphStructureListeners about the removed connection.
void	fireNodeAddedEvent(INodeLayout node) Notifies all previously registered IGraphStructureListeners about the newly added node.
void	fireNodeMovedEvent(INodeLayout node) Notifies all previously registered ILayoutListeners about the moved node.
void	fireNodeRemovedEvent(INodeLayout node) Notifies all previously registered IGraphStructureListeners about the removed node.
void	fireNodeResizedEvent(INodeLayout node) Notifies all previously registered ILayoutListeners about the resized node.
void	firePruningEnableChangedEvent() Notifies all previously registered IContextListeners about the state of the pruning flag.
void	fireSubgraphMovedEvent(ISubgraphLayout subgraph) Notifies all previously registered ILayoutListeners about the moved subgraph.
void	fireSubgraphResizedEvent(ISubgraphLayout subgraph) Notifies all previously registered ILayoutListeners about the resized subgraph.
void	flushChanges(boolean animationHint) Causes all the changes made to elements in this context to affect the display.
IConnectionLayout[]	getConnections() Returns all the connections between nodes that should be laid out.
IConnectionLayout[]	getConnections(IEntityLayout layoutEntity1, IEntityLayout layoutEntity2) Returns all the connections between given source and target entities.
ILayoutAlgorithm	getDynamicLayoutAlgorithm()
IEntityLayout[]	getEntities() Returns all entities that are currently placed on the graph, that is subgraphs and unpruned nodes.
INodeLayout[]	getNodes() Returns all the nodes that should be laid out.
ILayoutAlgorithm	getStaticLayoutAlgorithm() Returns the static layout algorithm used to layout a newly initialized graph or after heavy changes to it.
ISubgraphLayout[]	getSubgraphs() Returns all the subgraphs this context's nodes were pruned to.
boolean	isLayoutIrrelevant(IConnectionLayout connLayout) Returns true when the given IConnectionLayout is not relevant for layout according to the configured layout filters.
boolean	isLayoutIrrelevant(INodeLayout nodeLayout) Returns true when the given INodeLayout is not relevant for layout according to the configured layout filters.
void	removeContextListener(IContextListener listener) Removes a context listener from this context.
void	removeGraphStructureListener(IGraphStructureListener listener) Removes a graph structure listener from this context.
void	removeLayoutFilter(ILayoutFilter layoutFilter) Removes the given ILayoutFilter from this ILayoutContext.
void	removeLayoutListener(ILayoutListener listener) Removes a layout listener from this context.
void	removePruningListener(IPruningListener listener) Removes a pruning structure listener from this context.
void	schedulePostLayoutPass(java.lang.Runnable runnable) Adds the given Runnable to the list of runnables which are called when this ILayoutContext is asked to apply all changes made to its elements to the display, i.e. within flushChanges(boolean).
void	schedulePreLayoutPass(java.lang.Runnable runnable) Adds the given Runnable to the list of Runnables which are executed before applying a layout, i.e. before applyDynamicLayout(boolean) or applyStaticLayout(boolean).
void	setDynamicLayoutAlgorithm(ILayoutAlgorithm algorithm) Sets the dynamic layout algorithm for this context.
void	setStaticLayoutAlgorithm(ILayoutAlgorithm algorithm) Sets the static layout algorithm for this context.
void	unschedulePostLayoutPass(java.lang.Runnable runnable) Removes the given Runnable from the list of runnables which are called when this ILayoutContext is asked to apply all changes made to its elements to the display, i.e. within flushChanges(boolean).
void	unschedulePreLayoutPass(java.lang.Runnable runnable) Removes the given Runnable from the list of Runnables which are executed before applying a layout, i.e. before applyDynamicLayout(boolean) or applyStaticLayout(boolean).

Methods inherited from interface org.eclipse.gef4.common.properties.IPropertyStore

getProperty, setProperty

Methods inherited from interface org.eclipse.gef4.common.properties.IPropertyChangeNotifier

addPropertyChangeListener, removePropertyChangeListener

Field Detail

STATIC_LAYOUT_ALGORITHM_PROPERTY

static final java.lang.String STATIC_LAYOUT_ALGORITHM_PROPERTY

An ILayoutContext notifies registered listeners about changes to the static layout algorithm using this property name.

See Also:

Constant Field Values

DYNAMIC_LAYOUT_ALGORITHM_PROPERTY

static final java.lang.String DYNAMIC_LAYOUT_ALGORITHM_PROPERTY

An ILayoutContext notifies registered listeners about changes to the dynamic layout algorithm using this property name.

See Also:

Constant Field Values

Method Detail

applyDynamicLayout

void applyDynamicLayout(boolean clean)

Applies the background layout algorithm of this LayoutContext. The clean flag is passed-in to the background layout algorithm to indicate whether the context changed significantly since the last layout pass.

Parameters:

clean - true to indicate that the algorithm has to fully re-compute the layout, otherwise false.

applyStaticLayout

void applyStaticLayout(boolean clean)

Applies the static layout algorithm of this LayoutContext. The clean flag is passed-in to the static layout algorithm to indicate whether the context changed significantly since the last layout pass.

Parameters:

clean - true to indicate that the algorithm has to fully re-compute the layout, otherwise false.

getNodes

INodeLayout[] getNodes()

Returns all the nodes that should be laid out. Replacing elements in the returned array does not affect this context.

Returns:

array of nodes to lay out

getConnections

IConnectionLayout[] getConnections()

Returns all the connections between nodes that should be laid out. Replacing elements in the returned array does not affect this context.

Returns:

array of connections between nodes

getEntities

IEntityLayout[] getEntities()

Returns all entities that are currently placed on the graph, that is subgraphs and unpruned nodes. Replacing elements in the returned array does not affect this context.

Returns:

array of entities to layout

getConnections

IConnectionLayout[] getConnections(IEntityLayout layoutEntity1,
                                   IEntityLayout layoutEntity2)

Returns all the connections between given source and target entities. If given entity is a subgraph, connections adjacent to each of its nodes will be included in the result. All the undirected nodes connecting the two nodes will be also included in the result. Replacing elements in the returned array does not affect this context.

Parameters:

layoutEntity1 - The source entity.

layoutEntity2 - The target entity.

Returns:

The connections between the source and target entities.

getSubgraphs

ISubgraphLayout[] getSubgraphs()

Returns all the subgraphs this context's nodes were pruned to. Replacing elements in the returned array does not affect this context.

Returns:

array of subgraphs (may be empty)

createSubgraph

ISubgraphLayout createSubgraph(INodeLayout[] nodes)

Creates a subgraph containing given nodes and adds it to this context. If given nodes already belong to another subgraphs, they are removed from them prior to adding to the new subgraph.

Parameters:

nodes - nodes to add to the new subgraph

Returns:

The newly created ISubgraphLayout.

setDynamicLayoutAlgorithm

void setDynamicLayoutAlgorithm(ILayoutAlgorithm algorithm)

Sets the dynamic layout algorithm for this context. This algorithm will be used to relayout graph items using ILayoutAlgorithm.applyLayout(boolean) after every event that is not intercepted by any listener when currently changes are not being flushed and background layout is enabled. The clean flag for the background layout algorithm can be set to false by the context when reacting to events.

Parameters:

algorithm - The new dynamic ILayoutAlgorithm for this ILayoutContext.

setStaticLayoutAlgorithm

void setStaticLayoutAlgorithm(ILayoutAlgorithm algorithm)

Sets the static layout algorithm for this context. The static algorithm has to be manually invoked, for example, after significant changes to the context.

Parameters:

algorithm - The new static ILayoutAlgorithm for this ILayoutContext.

schedulePostLayoutPass

void schedulePostLayoutPass(java.lang.Runnable runnable)

Adds the given Runnable to the list of runnables which are called when this ILayoutContext is asked to apply all changes made to its elements to the display, i.e. within flushChanges(boolean).

Parameters:

runnable - A Runnable called whenever this context is asked to apply all changes made to its elements to the display.

unschedulePostLayoutPass

void unschedulePostLayoutPass(java.lang.Runnable runnable)

Removes the given Runnable from the list of runnables which are called when this ILayoutContext is asked to apply all changes made to its elements to the display, i.e. within flushChanges(boolean).

Parameters:

runnable - The Runnable that should no longer get called when flushing changes.

isLayoutIrrelevant

boolean isLayoutIrrelevant(IConnectionLayout connLayout)

Returns true when the given IConnectionLayout is not relevant for layout according to the configured layout filters. Otherwise returns false.

Parameters:

connLayout - The IConnectionLayout in question.

Returns:

true when the given IConnectionLayout is not relevant for layout according to the configure layout filters, otherwise false.

isLayoutIrrelevant

boolean isLayoutIrrelevant(INodeLayout nodeLayout)

Returns true when the given INodeLayout is not relevant for layout according to the configured layout filters. Otherwise returns false.

Parameters:

nodeLayout - The INodeLayout in question.

Returns:

true when the given INodeLayout is not relevant for layout according to the configure layout filters, otherwise false.

addLayoutFilter

void addLayoutFilter(ILayoutFilter layoutFilter)

Adds the given ILayoutFilter to this ILayoutContext.

Parameters:

layoutFilter - The ILayoutFilter to add to this context.

removeLayoutFilter

void removeLayoutFilter(ILayoutFilter layoutFilter)

Removes the given ILayoutFilter from this ILayoutContext.

Parameters:

layoutFilter - The ILayoutFilter to remove to this context.

getStaticLayoutAlgorithm

ILayoutAlgorithm getStaticLayoutAlgorithm()

Returns the static layout algorithm used to layout a newly initialized graph or after heavy changes to it.

Returns:

the static layout algorithm

getDynamicLayoutAlgorithm

ILayoutAlgorithm getDynamicLayoutAlgorithm()

Returns:

the background algorithm of this context (see setDynamicLayoutAlgorithm(ILayoutAlgorithm) for details)

addLayoutListener

void addLayoutListener(ILayoutListener listener)

Adds a listener to the context that will be notified about changes in this context's layout, that is movement and resizing of nodes / subgraphs. The notifications will not include changes made with API included in layout related interfaces, so that layout algorithms won't be notified about changes they invoke. Only internal changes of the system will fire events.

Parameters:

listener - listener to add

removeLayoutListener

void removeLayoutListener(ILayoutListener listener)

Removes a layout listener from this context.

Parameters:

listener - listener to remove

addGraphStructureListener

void addGraphStructureListener(IGraphStructureListener listener)

Adds a listener to the context that will be notified about changes in graph structure, that is addition and removal of nodes and connections. The notifications will not include changes made with API included in layout related interfaces, so that layout algorithms won't be notified about changes they invoke. Only internal changes of the system will fire events.

Parameters:

listener - listener to add

removeGraphStructureListener

void removeGraphStructureListener(IGraphStructureListener listener)

Removes a graph structure listener from this context.

Parameters:

listener - listener to remove

addContextListener

void addContextListener(IContextListener listener)

Adds a listener to the context that will be notified about changes related to its configuration.

Parameters:

listener - listener to add

removeContextListener

void removeContextListener(IContextListener listener)

Removes a context listener from this context.

Parameters:

listener - listener to remove

addPruningListener

void addPruningListener(IPruningListener listener)

Adds a listener to the context that will be notified about changes in graph pruning, that is hiding and showing of nodes. The notifications will not include changes made with API included in layout related interfaces, so that layout algorithms won't be notified about changes they invoke. Only internal changes of the system will fire events.

Parameters:

listener - listener to add

removePruningListener

void removePruningListener(IPruningListener listener)

Removes a pruning structure listener from this context.

Parameters:

listener - listener to remove

flushChanges

void flushChanges(boolean animationHint)

Causes all the changes made to elements in this context to affect the display. Called from layout algorithms on finish of layout.

Parameters:

animationHint - a hint for display mechanism indicating whether changes are major and should be animated (if true) or not.

fireNodeAddedEvent

void fireNodeAddedEvent(INodeLayout node)

Notifies all previously registered IGraphStructureListeners about the newly added node.

Parameters:

node - NodeLayout of newly added node

fireNodeRemovedEvent

void fireNodeRemovedEvent(INodeLayout node)

Notifies all previously registered IGraphStructureListeners about the removed node.

Parameters:

node - NodeLayout of removed node

fireConnectionAddedEvent

void fireConnectionAddedEvent(IConnectionLayout connection)

Notifies all previously registered IGraphStructureListeners about the newly added connection.

Parameters:

connection - ConnectionLayout of newly added connection

fireConnectionRemovedEvent

void fireConnectionRemovedEvent(IConnectionLayout connection)

Notifies all previously registered IGraphStructureListeners about the removed connection.

Parameters:

connection - ConnectionLayout of removed connection

fireBoundsChangedEvent

void fireBoundsChangedEvent()

Notifies all previously registered IContextListeners about the bounds change.

fireBackgroundEnableChangedEvent

void fireBackgroundEnableChangedEvent()

Notifies all previously registered IContextListeners about the state of the background layout flag.

fireNodeMovedEvent

void fireNodeMovedEvent(INodeLayout node)

Notifies all previously registered ILayoutListeners about the moved node.

Parameters:

node - NodeLayout of moved node

fireNodeResizedEvent

void fireNodeResizedEvent(INodeLayout node)

Notifies all previously registered ILayoutListeners about the resized node.

Parameters:

node - NodeLayout of resized node

fireSubgraphMovedEvent

void fireSubgraphMovedEvent(ISubgraphLayout subgraph)

Notifies all previously registered ILayoutListeners about the moved subgraph.

Parameters:

subgraph - SubgraphLayout of moved subgraph

fireSubgraphResizedEvent

void fireSubgraphResizedEvent(ISubgraphLayout subgraph)

Notifies all previously registered ILayoutListeners about the resized subgraph.

Parameters:

subgraph - SubgraphLayout of resized subgraph

firePruningEnableChangedEvent

void firePruningEnableChangedEvent()

Notifies all previously registered IContextListeners about the state of the pruning flag.

unschedulePreLayoutPass

void unschedulePreLayoutPass(java.lang.Runnable runnable)

Removes the given Runnable from the list of Runnables which are executed before applying a layout, i.e. before applyDynamicLayout(boolean) or applyStaticLayout(boolean).

Parameters:

runnable - The Runnable to remove from the list of Runnables which are executed before applying a layout.

schedulePreLayoutPass

void schedulePreLayoutPass(java.lang.Runnable runnable)

Adds the given Runnable to the list of Runnables which are executed before applying a layout, i.e. before applyDynamicLayout(boolean) or applyStaticLayout(boolean).

Parameters:

runnable - The Runnable to add to the list of Runnables which are executed before applying a layout.