ilog.views.event.adapter

Class IlvManagerContentChangedDispatcher

java.lang.Object

ilog.views.event.adapter.IlvManagerContentChangedDispatcher

All Implemented Interfaces:

ManagerContentChangedListener, EventListener

public abstract class IlvManagerContentChangedDispatcher
extends Object
implements ManagerContentChangedListener

An abstract dispatcher class for receiving manager content change events and dispatching them to the graphic objects who need to know about content changes. This class exists as convenience for creating listener objects.

The typical use case is when a graphic object must react when a related object changed. It is far too expensive to register each single graphic object as content listener on the manager. Instead, a manager content change dispatcher is registered which distributes the events to the changed objects.

The example below shows a sketch how this class can be used:

 public class IlvMyGraphic extends IlvGraphic
                           implements ManagerContentChangedListener
 {
   // acts as template, to know how to create similar dispatchers
   static MyManagerContentChangedDispatcher templateDisp =
     new MyManagerContentChangedDispatcher();

   public void setGraphicBag(IlvGraphicBag bag)
   {
     IlvGraphicBag oldBag = getGraphicBag();
     if (bag != oldBag) {
       if (oldBag != null) {
         IlvManagerContentChangedDispatcher dispatcher =
           IlvManagerContentChangedDispatcher.Get(oldBag, false, templateDisp);
         if (dispatcher != null)
           dispatcher.notifyRemove();
       }
       if (bag != null) {
         IlvManagerContentChangedDispatcher dispatcher =
           IlvManagerContentChangedDispatcher.Get(bag, true, templateDisp);
         if (dispatcher != null)
           dispatcher.notifyAdd();
       }
     }
     super.setGraphicBag(bag);
   }
 
   public void contentsChanged(ManagerContentChangedEvent event)
   {
     ... here are the operations to do when the object changed ...
   }

   // inner class of the specific dispatcher
   static class MyManagerContentChangedDispatcher extends IlvManagerContentChangedDispatcher
   {
      protected String getID()
      {
        return "MyManagerContentChangedDispatcher".intern();
      }

      protected IlvManagerContentChangedDispatcher create()
      {
        return new MyManagerContentChangedDispatcher();
      }

      protected void contentsChanged(IlvGraphic g,
                                     ManagerContentChangedEvent event)
      {
        if (g instanceof IlvMyGraphic) {
          ((IlvMyGraphic)g).contentsChanged(event);
        }
      }
   }
 }
 

Since:

JViews 8.8

See Also:

ManagerContentChangedListener, IlvManager.addManagerContentChangedListener(ilog.views.event.ManagerContentChangedListener), IlvManager.removeManagerContentChangedListener(ilog.views.event.ManagerContentChangedListener)

Constructor Summary

Constructors

Constructor and Description
IlvManagerContentChangedDispatcher() Creates a new manager content change dispatcher.

Method Summary

Modifier and Type	Method and Description
protected void	contentsChanged(IlvGraphic g, ManagerContentChangedEvent event) Reacts for the input graphic on content change events.
void	contentsChanged(ManagerContentChangedEvent event) Reacts on content change events.
protected abstract IlvManagerContentChangedDispatcher	create() Creates an instance of the manager content change dispatcher.
static IlvManagerContentChangedDispatcher	Get(IlvGraphicBag bag, boolean addIfNecessary, IlvManagerContentChangedDispatcher tmplate) Returns the listener for a manager.
protected abstract String	getID() Returns the unique ID of the dispatcher.
void	notifyAdd() Must be called whenever an IlvGraphic object is added to the related manager that wants to receive the content change event.
void	notifyRemove() Must be called whenever a IlvGraphic is removed from the related manager that wanted to receive the content change event.

Methods inherited from class java.lang.Object

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

Constructor Detail

IlvManagerContentChangedDispatcher

public IlvManagerContentChangedDispatcher()

Creates a new manager content change dispatcher.

Method Detail

getID

protected abstract String getID()

Returns the unique ID of the dispatcher. The string should be internalized for faster testing. If a manager needs a manager content change dispatcher, it is registered on the manager under this ID. Each manager has only exactly one shared listener for each ID.

create

protected abstract IlvManagerContentChangedDispatcher create()

Creates an instance of the manager content change dispatcher. A subclass should return an new instance of the same subclass.

Get

public static IlvManagerContentChangedDispatcher Get(IlvGraphicBag bag,
                                                     boolean addIfNecessary,
                                                     IlvManagerContentChangedDispatcher tmplate)

Returns the listener for a manager.

Parameters:

bag - The manager that needs this type of listener.

addIfNecessary - If true, it creates a new listener if none is installed yet at the input manager. If false, it returns null if no listener with the same ID as the input template is installed.

tmplate - The template that is used to determined the ID and how to create the listener.

notifyAdd

public void notifyAdd()

Must be called whenever an IlvGraphic object is added to the related manager that wants to receive the content change event.

notifyRemove

public void notifyRemove()

Must be called whenever a IlvGraphic is removed from the related manager that wanted to receive the content change event.

contentsChanged

public void contentsChanged(ManagerContentChangedEvent event)

Reacts on content change events.

Specified by:

contentsChanged in interface ManagerContentChangedListener

Parameters:

event - The content change event.

See Also:

IlvManager.addManagerContentChangedListener(ilog.views.event.ManagerContentChangedListener), IlvManager.removeManagerContentChangedListener(ilog.views.event.ManagerContentChangedListener), IlvManager.addManagerTreeContentChangedListener(ilog.views.event.ManagerContentChangedListener), IlvManager.removeManagerTreeContentChangedListener(ilog.views.event.ManagerContentChangedListener)

contentsChanged

protected void contentsChanged(IlvGraphic g,
                               ManagerContentChangedEvent event)

Reacts for the input graphic on content change events. This is called when the event contains a graphic object and is of the types

• ManagerContentChangedEvent.OBJECT_ADDED
• ManagerContentChangedEvent.OBJECT_REMOVED
• ManagerContentChangedEvent.OBJECT_BBOX_CHANGED
• ManagerContentChangedEvent.OBJECT_VISIBILITY_CHANGED
• ManagerContentChangedEvent.OBJECT_LAYER_CHANGED

Parameters:

g - The object that was selected or deselected.

event - The content change event.