Bug 135465 [smoke]An error occurred when new a casading Parameter
Description: An error occurred when new a casading Parameter Step to reproduce: 1.new a sample db data source and data set 2.New a cascading parameter group, named "gp1", 3.select the data set, then create two cascading parameters, one is row["customernumber"], named p1; the other is row["customername"] Actual result; error message occurred repeatly
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/CascadingParametersDialog.java
okEnable = false;
		}
		else
		{
			Iterator iter = inputParameterGroup.getParameters( ).iterator( );
			if ( !iter.hasNext( ) )
			{
				okEnable = false;
			}
			else
			{
				int count = 0;
				while ( iter.hasNext( ) )
				{
					Object obj = iter.next( );
					if ( obj instanceof ScalarParameterHandle )
					{
						ScalarParameterHandle param = (ScalarParameterHandle) obj;
						count++;
						if ( param.getValueExpr( ) == null )
						{
							okEnable = false;
							break;
						}
					}
				}
				okEnable &= ( count != 0 );
			}
		}
		getOkButton( ).setEnabled( okEnable );