Bug 121352 The data set binding property cannot be retrieved in report preview layout
In report preview page, the datasource/dataset property binding lists cannot be retrieved. The dataset binding can not work correctly in layout preview because it's value cannot get from the binding list. But in the data set edit page, the binding value can be got. You can refer to the attachment.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/command/ContentRecord.java
if ( add && state != UNDONE_STATE || !add && state == UNDONE_STATE )
		{
			ElementDefn contentDefn = (ElementDefn) content.getDefn( );
			list.addAll( ValidationExecutor.getValidationNodes( content,
					contentDefn.getTriggerDefnSet( ), false ) );
		}
		return list;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.activity.ActivityRecord#getPostTasks()
	 */
	protected List getPostTasks( )
	{
		List retValue = new ArrayList( );
		retValue.addAll( super.getPostTasks( ) );
		if ( container instanceof TableItem || container instanceof TableGroup
				|| container instanceof TableRow )
		{
			TableItem table = LayoutUtil.getTableContainer( container );
			if ( table != null )
				retValue.add( new LayoutActivityTask( module, table ) );
		}
		
		NotificationEvent event = null;
		if ( add && state != UNDONE_STATE || !add && state == UNDONE_STATE )
			event = new ContentEvent( container, content, slotID,
					ContentEvent.ADD );