WebObjects: WODisplayGroup Delegate Method Does Not Function

The WODisplayGroup delegate method displayGroupDidSetValue described in the WebObjects documentation does not work in a WebObjects application.
Symptom

Using the WODisplayGroup delegate method displayGroupDidSetValue in a WebObjects application does not work.


Solution

None for WODisplayGroup. However, this delegate method works properly with EODisplayGroup in Enterprise Objects Frameworks (EOF).

Additional Information

Display Group Description

A display group transports values between an enterprise object and a user interface object. An EODisplayGroup is used in a desktop application with Enterprise Objects Frameworks (EOF), while a WODisplayGroup is used in a WebObjects application. The functionality of a WODisplayGroup and an EODisplayGroup are identical.

The WODisplayGroup delegate method described below informs the delegate that aDisplayGroup has altered a property value of anObject.

key identifies the property, and value is its new value.

Objective-C: (WebObjects Release 4.5 and 4.5.1)

-(void) displayGroup:(WODisplayGroup *) aDisplayGroup didSetValue: (id) value forObject: (id) anObject key: (NSString *) key

Bridged Java: (WebObjects Release 4.5 and 4.5.1)

Package: com.apple.yellow.webobjects

public abstract void displayGroupDidSetValue( WODisplayGroup aDisplayGroup, Object value, Object anObject, String key)

Pure Java: (WebObjects Release 5 and WebObjects 5.1)

Package: com.webobjects.appserver

public abstract void displayGroupDidSetValue( WODisplayGroup aDisplayGroup, Object value, Object anObject, String key)

However, this method is only implemented for EOF applications. Its counterpart in WebObjects does nothing because this delegate method relies on the implementation of EOAssociation, for which there is no equivalent in WebObjects.

Important: This method has been removed in WebObjects 5.2

Published Date: Feb 18, 2012