Bug 390669 [Accessibility]Press 'Tab' doesn't focus on the next report item when adding relative period aggregation.
xtab/org.eclipse.birt.report.item.crosstab.ui/src/org/eclipse/birt/report/item/crosstab/internal/ui/dialogs/CrosstabBindingDialogHelper.java
{
								modifyDialogContent( );
								validate( );
								paramsValueMap.put( param.getName( ),
										txtParam.getText( ) );
							}
						} );
						GridData gridData = new GridData( GridData.FILL_HORIZONTAL );
						gridData.horizontalIndent = 0;
						gridData.horizontalSpan = 2;
						gridData.heightHint = txtParam.computeSize( SWT.DEFAULT, SWT.DEFAULT ).y
								- txtParam.getBorderWidth( )
								* 2;
						txtParam.setLayoutData( gridData );
						createExpressionButton( paramsComposite, txtParam );
						paramsMap.put( param.getName( ), txtParam );
					}
				}
			}
			else
			{
				( (GridData) paramsComposite.getLayoutData( ) ).heightHint = 0;
				
				
			}
			
			try
			{
				cmbType.setText( getDataTypeDisplayName( DataAdapterUtil.adapterToModelDataType( DataUtil.getAggregationManager( )
						.getAggregation( function.getName( ) )