Bug 146796 Error message pop up if display text contain non-digital char when add next item
Description: In decimal type parameter creation,display type is "list box", Error message pop up if "display text" contain non-digital char when add next item. Steps: 1.Create a new decimal parameter 2.Set display type as "list box" 3.Input one item: value:1, display text:test 4.Input another item: Value:2 Actual result: error message pop up: The display text already exists! Expected result: Input item succussfully.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ParameterDialog.java
return PARAM_CONTROL_LIST;
		}
		return controlType.findChoiceByDisplayName( displayText ).getName( );
	}
	private void changeDataType( )
	{
		String type = getSelectedDataType( );
		if ( type.equals( lastDataType ) )
		{
			return;
		}
		if ( buildControlTypeList( type ) )
		{
			changeControlType( );
		}
		lastDataType = type;
		initFormatField( );
		if ( isStatic( ) )
		{
			makeUniqueAndValid( );
			refreshValueTable( );
		}
		else
		{
			refreshColumns( true );
		}
		updateMessageLine( );
	}
	private boolean buildControlTypeList( String type )
	{