After upgrading to Apex 4.2 the following error occurrs when loading a page that contains a Group Select List [Plug-in]:
*'apex.widget.tabular' is null or not an object*
The error message appears to be related to a Group Select List [Plug-in] item with the following assigned List of Values attributes(options):
Display Null Value: Yes
Null Display Value: -
Null Return Value: NULL
Note: The application requires a NULL option to be displayed in the list of values (display = '-', value = null). This works fine in Apex 4.1...
Removing the above values does eliminate the error message. However entering any value into the Null Display Value and Null Return Value item attributes causes the error message to reappear.
Is this a known Group Select List [Plug-in] issue/bug? Any ideas on how to work around this issue would be greatly appreciated.
http://apex.oracle.com/plugins contains an updated version of the Group Selectlist plug-in (v1.1) which should fix your problem. Just import it into your application and you should be done.