Bug 122177 Add input for IntervalBase to Group Editor
BIRT model's group definition has one important property: IntervalBase (see GroupHandle.setIntervalBase). This property controls how interval-based grouping picks the range of its initial group, and is an important part of range-based grouping. BIRT designer's Group Details editor should allow user to edit IntervalBase for a group. This is how the editor should work: * IntervalBase options should be presented only if "Interval" is not "None". (Since IntervalBase only makes sense for interval-based grouping) * IntervalBase should be presented in conjunction with checkbox. When it is unchecked (maps to a NULL IntervalBase value), Data Engine dynamically picks a base value using the first group key value in the result set. When it is checked, the user should input a base value. The following is a suggested look of the UI control: [ ] Use fixed base value for interval: _______________ ( [] is a checkbox, underline ___ is a textbox ).
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/GroupDialog.java
slotHandle,
							inputGroup.getContainer( ) );
					slotHandle.add( dataItemHandle );
				}
			}
			index = intervalType.getSelectionIndex( );
			inputGroup.setInterval( intervalChoices[index].getName( ) );
			if ( index != 0 )
			{
				inputGroup.setIntervalRange( intervalRange.getSelection( ) );
			}
			if ( inputGroup instanceof TableGroupHandle )
			{
				if ( includeHeader.getSelection( ) != inputGroup.hasHeader( ) )
				{
					if ( includeHeader.getSelection( ) )
					{
						inputGroup.getHeader( ).add( createRow( ) );
					}
					else
					{
						inputGroup.clearContents( GroupHandle.HEADER_SLOT );
					}
				}
				if ( includeFooter.getSelection( ) != inputGroup.hasFooter( ) )
				{
					if ( includeFooter.getSelection( ) )
					{
						inputGroup.getFooter( ).add( createRow( ) );
					}