com.webobjects.eointerface
Class EOMasterDetailAssociation

java.lang.Object
  |
  +--com.webobjects.eocontrol.EODelayedObserver
        |
        +--com.webobjects.eointerface.EOAssociation
              |
              +--com.webobjects.eointerface.EOMasterAssociation
                    |
                    +--com.webobjects.eointerface.EOMasterDetailAssociation

All Implemented Interfaces:

EOObserving, NSDisposable

Direct Known Subclasses:

EOMasterPeerAssociation

public class EOMasterDetailAssociation

extends EOMasterAssociation

An EOMasterDetailAssociation object binds one EODisplayGroup (the detail) to a relationship in another (the master), so that the detail display group contains the destination objects for the object selected in the master. The display group's data sources also operate in a master-detail arrangement, meaning changes to one are immediately reflected in the other. In this arrangement, the detail EODisplayGroup's data source must be an EODetailDataSource. The detail objects are taken directly from the selected object in the master EODisplayGroup, so that changes to the objects in one EODisplayGroup are instantly reflected in the other.

In com.webobjects.eointerface.cocoa, by contrast, with an EOMasterPeerAssociation, the two EODisplayGroups are independent of each other. In a master-peer setup, insertions and deletions in the detail EODisplayGroup don't affect the corresponding relationship property of the selected object in the master EODisplayGroup. Master-peer setups are more appropriate when no insertions or deletions will be made in the detail EODisplayGroup. See the EOMasterPeerAssociation class specification for more information.

Usable With:
EODisplayGroup with a null or detail datasource

Aspects

parent

An EODisplayGroup with which the association's display group should be synchronized.

Example

Suppose you have a master EODisplayGroup displaying Movie objects and a detail display group displaying Talent objects. The two display groups are bound to one another through Movie's directors relationship -- a to-many relationship from Movie to Talent. When a Movie is selected, you want the Talent display group to display the Talents who directed the Movie. Inserting a new director into the Talent display group should add the director to the selected Movie's directors relationship; and similarly, deleting a director from the Talent display group should remove the director from the selected Movie's directors relationship.

To do this, in Interface Builder, Control-drag a connection from the Talent display group to the Movie display group. In the Connections inspector, choose EOMasterDetailAssociation, and bind parent aspect to the directors key.

Fields inherited from class com.webobjects.eointerface.EOAssociation

ActionAspect, ArgumentAspect, AttributeAspectSignature, AttributeToManyAspectSignature, AttributeToOneAspectSignature, AttributeToOneToManyAspectSignature, BackgroundColorAspect, BoldAspect, ChildrenAspect, DestinationAspect, EnabledAspect, ExpandedIconAspect, IconAspect, IgnoreValue, IsLeafAspect, ItalicAspect, MatchKey1Aspect, MatchKey2Aspect, MatchKey3Aspect, NullAspectSignature, ParentAspect, RootAspect, SelectedIndexAspect, SelectedObjectAspect, SelectedTitleAspect, SetValue, SourceAspect, TextColorAspect, TitlesAspect, ToManyAspectSignature, ToOneAspectSignature, ToOneToManyAspectSignature, UnsetValue, URLAspect, ValueAspect

Fields inherited from class com.webobjects.eocontrol.EODelayedObserver

ObserverNumberOfPriorities, ObserverPriorityFifth, ObserverPriorityFirst, ObserverPriorityFourth, ObserverPriorityImmediate, ObserverPriorityLater, ObserverPrioritySecond, ObserverPrioritySixth, ObserverPriorityThird

Constructor Summary

EOMasterDetailAssociation(Object object)
Creates a new EOMasterDetailAssociation to monitor and update the objects in object, an EODisplayGroup.

Method Summary

void	dispose() Clears all references this association has to other objects, especially its display object and EODisplayGroup.
boolean	isUsableWithObject(Object object) Returns true if object is an instance of EODisplayGroup and its data source is either null or an EODetailDataSource (EOControl).
void	subjectChanged() See the subjectChanged method description in the superclass EOAssociation.

Methods inherited from class com.webobjects.eointerface.EOMasterAssociation

primaryAspect, priority

Methods inherited from class com.webobjects.eointerface.EOAssociation

aspects, aspectSignatures, associationClassesForObject, bindAspect, breakConnection, copyMatchingBindingsFromAssociation, displayGroupForAspect, displayGroupKeyForAspect, endEditing, establishConnection, isConnected, isEnabled, isEnabledAtIndex, isExplicitlyDisabled, object, objectKeysTaken, registerAssociationClass, setExplicitlyDisabled, setObject, setValueForAspect, setValueForAspectAtIndex, shouldEndEditing, shouldEndEditingAtIndex, valueForAspect, valueForAspectAtIndex

Methods inherited from class com.webobjects.eocontrol.EODelayedObserver

discardPendingNotification, objectWillChange, observerQueue

Methods inherited from class java.lang.Object

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

Constructor Detail

EOMasterDetailAssociation

public EOMasterDetailAssociation(Object object)

Creates a new EOMasterDetailAssociation to monitor and update the objects in object, an EODisplayGroup. You normally set up associations with Interface Builder, in which case you don't need to create them programmatically. However, if you do create them up programmatically, setting them up is a multi-step process. After creating an association, you must bind its aspects and establish its connections.

Parameters:

object - EODisplayGroup for this association to monitor and update

See Also:

EOAssociation.bindAspect(java.lang.String, com.webobjects.eointerface.EODisplayGroup, java.lang.String), EOAssociation.establishConnection()

Method Detail

dispose

public void dispose()

Clears all references this association has to other objects, especially its display object and EODisplayGroup. Call this method before nulling out a reference to this association to ensure it gets garbage collected properly. Subclasses should override this method to do any additional cleanup that may be needed and invoke super's implementation at the end.

Overrides:

dispose in class EOAssociation

See Also:

NSDisposable

isUsableWithObject

public boolean isUsableWithObject(Object object)

Returns true if object is an instance of EODisplayGroup and its data source is either null or an EODetailDataSource (EOControl).

Overrides:

isUsableWithObject in class EOMasterAssociation

Parameters:

object - this method should verify that object is usable with the association.

Returns:

true if object is an instance of EODisplayGroup and its data source is either null or an EODetailDataSource (EOControl)

See Also:

EOAssociation.isUsableWithObject(java.lang.Object)

subjectChanged

public void subjectChanged()

See the subjectChanged method description in the superclass EOAssociation.

Overrides:

subjectChanged in class EOAssociation

See Also:

EOAssociation.subjectChanged()