y.view
Class CreateEdgeMode

java.lang.Object
  y.view.ViewMode
      y.view.CreateEdgeMode

All Implemented Interfaces:

MouseListener, MouseMotionListener, EventListener, MouseInputListener

Direct Known Subclasses:

HierarchyCreateEdgeMode

public class CreateEdgeMode
extends ViewMode

This view mode is responsible for creating edges.

An edge is created with this mode in the following way:

• Press with the left mouse button on a node and start dragging the mouse from there. The pressed node is the source node for the edge to be created.
• Release the mouse over another node. That node is the target node for the created edge.
• One can create bends for the edge during the creation by releasing the mouse on the view background. Any consecutive bend can be created by clicking on the view background again. When bends were created then the creation of the edge ends with a click on a node. That node is the target node for the created edge.
• To remove a newly created bend use a right click with the mouse. If there are no bends that can be removed the creation of the whole edge will be terminated by a right click.
• In order to cancel edge creation, simply press the escape key (which is the default cancel key).

The default edge realizer of the Graph2D will be assigned to the newly created edge.

This mode provides several options, e.g.:

• it is possible to allow or disallow the creation of bends
• edge creation can be restricted to orthogonal edge paths

This mode provides some hook methods that are meant to be overridden in order to influence its behavior.

Field Summary

Fields inherited from class y.view.ViewMode

ACTIVE_PROPERTY, ACTIVE_VIEW_PROPERTY, CHILD_MODE_PROPERTY, EDITING_PROPERTY, GRAB_FOCUS_ENABLED_PROPERTY, lastClickEvent, lastDragEvent, lastMoveEvent, lastPressEvent, lastReleaseEvent, MODIFIER_MASK_PROPERTY, NAME_PROPERTY, originalX, originalY, PARENT_MODE_PROPERTY, view

Constructor Summary

CreateEdgeMode()
Instantiates a new CreateEdgeMode.

CreateEdgeMode(ViewContainer view)
Instantiates a new CreateEdgeMode for a given ViewContainer

Method Summary

protected boolean	acceptBend(Node start, Node hitNode, double x, double y) Whether or not to accept the creation of a bend.
protected boolean	acceptSourceNode(Node source, double x, double y) This method gets called right before someone wants to start creating an edge at location (x,y) starting from node source.
protected boolean	acceptTargetNode(Node target, double x, double y) This method gets called right before someone wants to complete creating an edge at location (x,y) by connecting to node target.
protected void	addBend(EdgeRealizer realizer, double x, double y) Invoked when the bend creation mouse gesture occured and bend creation is allowed.
void	allowBendCreation(boolean b) Allows or disallows bend creation.
void	allowSelfloopCreation(boolean b) Allows or disallows selfloop creation.
protected void	cancelEdgeCreation() Calling this method cancels edge creation properly.
void	cancelEditing() This can be used to cleanly exit an edit that is currently in progress.
protected EdgeRealizer	createDummyEdgeRealizer() Factory method, which creates the dummy EdgeRealizer which is used during the edge creation process.
protected NodeRealizer	createDummySourceNodeRealizer(NodeRealizer currentRealizer) Creates a dummy node for the target node of the dummy edge By default, this method returns currentRealizer.createCopy();
protected NodeRealizer	createDummyTargetNodeRealizer(double x, double y) Creates a dummy node for the other end of the edge.
protected Edge	createEdge(Graph2D graph, Node startNode, Node targetNode, EdgeRealizer realizer) Callback method that is responsible for the actual creation of the edge.
protected Node	determineHitNode(Graph2D graph, double x, double y) Callback used during the dragging to determine the target hit node
boolean	doAllowBendCreation() Returns true iff the creation of bends should be allowed.
boolean	doAllowSelfloopCreation() Returns true iff the creation of selfloops should be allowed.
protected void	edgeCreated(Edge edge) This method gets called after a new edge was completely created by this mode.
protected void	edgeMoved(double x, double y) This method gets called whenever the dummy endpoint of the to be created edge has changed it's location.
int	getCancelKeyCode() Sets the virtual key code as defined in KeyEvent which cancels the edge creation.
protected EdgeRealizer	getDummyEdgeRealizer() Returns the dummy EdgeRealizer which is currently in use.
protected NodeRealizer	getDummySourceNodeRealizer() Returns the currently used dummy node realizer for the source node of the dummy edge.
protected NodeRealizer	getDummyTargetNodeRealizer() Returns the currently used dummy node realizer for the target node of the dummy edge.
protected YPoint	getSourcePortOffset(boolean modifierPressed, Node sourceNode, double dx, double dy) Invoked when the edge is about to be created.
protected YPoint	getTargetPortOffset(boolean modifierPressed, Node targetNode, double dx, double dy) Invoked when the edge has been created.
void	init() This method is called in a child mode when it gets installed in another mode.
boolean	isEarlyEdgeCancelingEnabled() Determines whether the edge creation should be canceled if the user released the mouse inside the source node before even leaving it once.
boolean	isOrthogonalEdgeCreation() Determines whether this mode creates orthogonally routed edges.
void	mouseDraggedLeft(double x, double y) Moves the dummy end of the edge while the actual target node is unknown.
void	mouseMoved(double x, double y) Moves the dummy end of the edge while the actual target node is unknown.
void	mousePressedLeft(double x, double y) Initiates the creation of an edge.
void	mouseReleasedLeft(double x, double y) If a node was hit at the given coordinates, that node will be used as target node for the newly created edge.
void	mouseReleasedRight(double x, double y) Removes a bend if possible. otherwise cancels edge creation.
void	mouseShiftPressedLeft(double x, double y) Initiates the creation of an edge.
void	mouseShiftReleasedLeft(double x, double y) If a node was hit at the given coordinates, that node will be used as target node for the newly created edge.
void	reactivateParent() The parent of this ViewMode is reactivated and this ViewMode is deactivated.
protected void	removeBend(EdgeRealizer edgeRealizer, int index) Callback used by mouseReleasedRight(double, double) that actually removes the given bend from the edge.
void	setCancelKeyCode(int cancelKeyCode) Sets the virtual key code as defined in KeyEvent which cancels the edge creation.
void	setEarlyEdgeCancelingEnabled(boolean earlyEdgeCancelingEnabled) Determines whether the edge creation should be canceled if the user released the mouse inside the source node before even leaving it once.
void	setOrthogonalEdgeCreation(boolean orthogonalEdgeCreation) Determines whether this mode should create orthogonally routed edges, only.
protected void	sourceNodeDeclined(Node target, double x, double y) This method gets called in case method acceptSourceNode(Node, double, double) returns false.
protected void	targetNodeDeclined(Node target, double x, double y) This method gets called in case method acceptTargetNode(Node, double, double) returns false.

Methods inherited from class y.view.ViewMode

activate, addPropertyChangeListener, addPropertyChangeListener, firePropertyChange, firePropertyChange, firePropertyChange, getChild, getGraph2D, getGridX, getGridY, getHitInfo, getHitInfo, getLastHitInfo, getModifierMask, getName, getParent, isActive, isEditing, isGrabFocusEnabled, isGridMode, isModifierPressed, mouseClicked, mouseClicked, mouseDragged, mouseDraggedMiddle, mouseDraggedRight, mouseEntered, mouseExited, mouseMoved, mousePressed, mousePressedMiddle, mousePressedRight, mouseReleased, mouseReleased, mouseReleasedMiddle, mouseShiftPressedMiddle, mouseShiftPressedRight, mouseShiftReleasedMiddle, mouseShiftReleasedRight, removePropertyChangeListener, removePropertyChangeListener, setActiveView, setChild, setChild, setEditing, setGrabFocusEnabled, setGridMode, setLastHitInfo, setModifierMask, setName, setParent, translateX, translateY

Methods inherited from class java.lang.Object

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

Constructor Detail

CreateEdgeMode

public CreateEdgeMode(ViewContainer view)

Instantiates a new CreateEdgeMode for a given ViewContainer

CreateEdgeMode

public CreateEdgeMode()

Instantiates a new CreateEdgeMode.

Method Detail

init

public void init()

Description copied from class: ViewMode

This method is called in a child mode when it gets installed in another mode.

Overrides:

init in class ViewMode

See Also:

ViewMode.setChild(ViewMode,MouseEvent,MouseEvent)

allowBendCreation

public void allowBendCreation(boolean b)

Allows or disallows bend creation. By default bend creation is allowed.

doAllowBendCreation

public boolean doAllowBendCreation()

Returns true iff the creation of bends should be allowed. This mode will act according to the return value of this method.

allowSelfloopCreation

public void allowSelfloopCreation(boolean b)

Allows or disallows selfloop creation. By default selfloopcreation is allowed.

doAllowSelfloopCreation

public boolean doAllowSelfloopCreation()

Returns true iff the creation of selfloops should be allowed. This mode will act according to the return value of this method.

mousePressedLeft

public void mousePressedLeft(double x,
                             double y)

Initiates the creation of an edge.

Overrides:

mousePressedLeft in class ViewMode

Parameters:

x - the x-coordinate of the mouse event in world coordinates.

y - the y-coordinate of the mouse event in world coordinates.

mouseShiftPressedLeft

public void mouseShiftPressedLeft(double x,
                                  double y)

Initiates the creation of an edge. By pressing shift a source port for that edge at the given location will be assigned.

Overrides:

mouseShiftPressedLeft in class ViewMode

Parameters:

x - the x-coordinate of the mouse event in world coordinates.

y - the y-coordinate of the mouse event in world coordinates.

getSourcePortOffset

protected YPoint getSourcePortOffset(boolean modifierPressed,
                                     Node sourceNode,
                                     double dx,
                                     double dy)

Invoked when the edge is about to be created. This method can be used to adjust the source port offset. This implementation returns YPoint.ORIGIN if the modifier is false, otherwise the ViewMode.getGridX(double) and ViewMode.getGridY(double) methods are used to snap to the next availabe grid point.

Parameters:

modifierPressed - indicates if the user wants to have an alternative port assignment

sourceNode - the node which will be the source of the newly created edge

dx - the x offset were the click occured on the node

dy - the y offset were the click occured on the node

Returns:

the offset should be assigned to the newly created source port.

createDummyEdgeRealizer

protected EdgeRealizer createDummyEdgeRealizer()

Factory method, which creates the dummy EdgeRealizer which is used during the edge creation process. By default, this method returns getGraph2D().getDefaultEdgeRealizer().createCopy();

getDummyEdgeRealizer

protected EdgeRealizer getDummyEdgeRealizer()

Returns the dummy EdgeRealizer which is currently in use.

Throws:

IllegalStateException - if the edge has not yet been created

createDummySourceNodeRealizer

protected NodeRealizer createDummySourceNodeRealizer(NodeRealizer currentRealizer)

Creates a dummy node for the target node of the dummy edge By default, this method returns currentRealizer.createCopy();

createDummyTargetNodeRealizer

protected NodeRealizer createDummyTargetNodeRealizer(double x,
                                                     double y)

Creates a dummy node for the other end of the edge. This implementation returns a zero width/ zero height ShapeNodeRealizer

Parameters:

x - the initial x coordinate

y - the initial y coordinate

Returns:

the created dummy target realizer

getDummyTargetNodeRealizer

protected NodeRealizer getDummyTargetNodeRealizer()

Returns the currently used dummy node realizer for the target node of the dummy edge.

Throws:

IllegalStateException - if the edge has not yet been created

Returns:

the realizer

getDummySourceNodeRealizer

protected NodeRealizer getDummySourceNodeRealizer()

Returns the currently used dummy node realizer for the source node of the dummy edge.

Throws:

IllegalStateException - if the edge has not yet been created

Returns:

the realizer

mouseReleasedRight

public void mouseReleasedRight(double x,
                               double y)

Removes a bend if possible. otherwise cancels edge creation.

Overrides:

mouseReleasedRight in class ViewMode

Parameters:

x - the x-coordinate of the mouse event in world coordinates.

y - the y-coordinate of the mouse event in world coordinates.

removeBend

protected void removeBend(EdgeRealizer edgeRealizer,
                          int index)

Callback used by mouseReleasedRight(double, double) that actually removes the given bend from the edge.

Parameters:

edgeRealizer - the dummy realizer that is used for displaying the edge during the creation.

index - the index of the bend to remove.

mouseShiftReleasedLeft

public void mouseShiftReleasedLeft(double x,
                                   double y)

If a node was hit at the given coordinates, that node will be used as target node for the newly created edge. By pressing shift a target port at the given coordinate will be assigned to the edge.

Overrides:

mouseShiftReleasedLeft in class ViewMode

Parameters:

x - the x-coordinate of the mouse event in world coordinates.

y - the y-coordinate of the mouse event in world coordinates.

mouseReleasedLeft

public void mouseReleasedLeft(double x,
                              double y)

If a node was hit at the given coordinates, that node will be used as target node for the newly created edge.

Overrides:

mouseReleasedLeft in class ViewMode

Parameters:

x - the x-coordinate of the mouse event in world coordinates.

y - the y-coordinate of the mouse event in world coordinates.

addBend

protected void addBend(EdgeRealizer realizer,
                       double x,
                       double y)

Invoked when the bend creation mouse gesture occured and bend creation is allowed.

Parameters:

realizer - The realizer for the edge that is being created.

x - The x coordinate where the mouse gesture occured.

y - The y coordinate where the mouse gesture occured.

getTargetPortOffset

protected YPoint getTargetPortOffset(boolean modifierPressed,
                                     Node targetNode,
                                     double dx,
                                     double dy)

Invoked when the edge has been created. This method can be used to adjust the target port offset. This implementation returns YPoint.ORIGIN if the modifier is false, otherwise the ViewMode.getGridX(double) and ViewMode.getGridY(double) methods are used to snap to the next availabe grid point.

Parameters:

modifierPressed - indicates if the user wants to have an alternative port assignment

targetNode - the node which is the target of the newly created edge

dx - the x offset where the click occured on the node

dy - the y offset where the click occured on the node

Returns:

the offset that should be assigned to the newly created target port.

createEdge

protected Edge createEdge(Graph2D graph,
                          Node startNode,
                          Node targetNode,
                          EdgeRealizer realizer)

Callback method that is responsible for the actual creation of the edge. This implementation returns graph.createEdge(startNode, targetNode, realizer)

Parameters:

graph - the graph to create the edge in

startNode - the start node of the edge

targetNode - the target node of the edge

realizer - the realizer to use (may be replaced or altered by subclass implementations)

Returns:

the newly created Edge or null if no edge should be created

acceptBend

protected boolean acceptBend(Node start,
                             Node hitNode,
                             double x,
                             double y)

Whether or not to accept the creation of a bend.

Parameters:

start - the node from where edge creation started

hitNode - the node that was hit at the given location

x - the x-coordinate of the current location

y - the y-coordinate of the current location

mouseDraggedLeft

public void mouseDraggedLeft(double x,
                             double y)

Moves the dummy end of the edge while the actual target node is unknown.

Overrides:

mouseDraggedLeft in class ViewMode

Parameters:

x - the x-coordinate of the mouse event in world coordinates.

y - the y-coordinate of the mouse event in world coordinates.

determineHitNode

protected Node determineHitNode(Graph2D graph,
                                double x,
                                double y)

Callback used during the dragging to determine the target hit node

Parameters:

graph - the graph that can be used for hittesting

x - the x position of the mouse (not yet snapped to grid coordinates)

y - the y position of the mouse (not yet snapped to grid coordinates)

Returns:

the node that will be used as the target

mouseMoved

public void mouseMoved(double x,
                       double y)

Moves the dummy end of the edge while the actual target node is unknown.

Overrides:

mouseMoved in class ViewMode

Parameters:

x - the x-coordinate of the mouse event in world coordinates.

y - the y-coordinate of the mouse event in world coordinates.

reactivateParent

public void reactivateParent()

Description copied from class: ViewMode

The parent of this ViewMode is reactivated and this ViewMode is deactivated.

Overrides:

reactivateParent in class ViewMode

isOrthogonalEdgeCreation

public boolean isOrthogonalEdgeCreation()

Determines whether this mode creates orthogonally routed edges. If enabled this mode will insert bends into the edge so that each segment is either horizontally or vertically routed. The default is false.

Returns:

whether to orthogonal edge creation is enabled

setOrthogonalEdgeCreation

public void setOrthogonalEdgeCreation(boolean orthogonalEdgeCreation)

Determines whether this mode should create orthogonally routed edges, only. If enabled this mode will insert bends into the edge so that each segment is either horizontally or vertically routed. The default is false.

Parameters:

orthogonalEdgeCreation - whether to enable orthogonal edge creation.

isEarlyEdgeCancelingEnabled

public boolean isEarlyEdgeCancelingEnabled()

Determines whether the edge creation should be canceled if the user released the mouse inside the source node before even leaving it once. The default is true.

Returns:

whether creation will be canceled early.

setEarlyEdgeCancelingEnabled

public void setEarlyEdgeCancelingEnabled(boolean earlyEdgeCancelingEnabled)

Determines whether the edge creation should be canceled if the user released the mouse inside the source node before even leaving it once. The default is true.

Parameters:

earlyEdgeCancelingEnabled - whether creation should be canceled early.

edgeMoved

protected void edgeMoved(double x,
                         double y)

This method gets called whenever the dummy endpoint of the to be created edge has changed it's location. By default this method does nothing.

Parameters:

x - the x-coordinate of the endpoint

y - the y-coordinate of the endpoint

edgeCreated

protected void edgeCreated(Edge edge)

This method gets called after a new edge was completely created by this mode. It serves as a hook to perform some actions after this event has happened. By default this method does nothing.

cancelEdgeCreation

protected void cancelEdgeCreation()

Calling this method cancels edge creation properly. After doing some cleanup it reactivates the parent if present. This method is meant to be called from within the targetNodeDeclined method in order to cancel edge creation properly.

acceptSourceNode

protected boolean acceptSourceNode(Node source,
                                   double x,
                                   double y)

This method gets called right before someone wants to start creating an edge at location (x,y) starting from node source. The return value of this method determines whether or not creating an edge from that node will actually be initiated.

By default this method returns true.

Subclasses may want to override this feature to forbid edge creation starting from certain nodes.

targetNodeDeclined

protected void targetNodeDeclined(Node target,
                                  double x,
                                  double y)

This method gets called in case method acceptTargetNode(Node, double, double) returns false. This method is meant as a hook to perform some post target declination code.

By default this method does nothing.

acceptTargetNode

protected boolean acceptTargetNode(Node target,
                                   double x,
                                   double y)

This method gets called right before someone wants to complete creating an edge at location (x,y) by connecting to node target. The return value of this method determines whether or not the creation of an edge to that node will be performed.

By default this method returns true.

Subclasses may want to override this feature to forbid connecting an edge to a certain node.

sourceNodeDeclined

protected void sourceNodeDeclined(Node target,
                                  double x,
                                  double y)

This method gets called in case method acceptSourceNode(Node, double, double) returns false. This method is meant as a hook to perform some post source declination code.

By default this method does nothing.

getCancelKeyCode

public int getCancelKeyCode()

Sets the virtual key code as defined in KeyEvent which cancels the edge creation. Negative values disable this feature. Default is KeyEvent.VK_ESCAPE.

setCancelKeyCode

public void setCancelKeyCode(int cancelKeyCode)

Sets the virtual key code as defined in KeyEvent which cancels the edge creation. Negative values disable this feature.

cancelEditing

public void cancelEditing()
                   throws UnsupportedOperationException

Description copied from class: ViewMode

This can be used to cleanly exit an edit that is currently in progress.
The implementation and interpretation of "cancelling" is left to subclasses. This implementation does nothing but calls setEditing(false) if ViewMode.isEditing() returns true

Overrides:

cancelEditing in class ViewMode

Throws:

UnsupportedOperationException - if the editing cannot be cancelled for any reason.