Bug 153405 Null parameter value is inconsistent between designer and preview
Description: Null parameter value is inconsistent between designer and preview Steps to reproduce: 1. New a report parameter, list-box, tick AllowNull. 2. Click New button, click OK without input anything. 3. Drag the parameter to Layout and preview Actual result: After step2, display text is "Null" and value is empty. However, when preview, the display text is "Null Value". Expected result: Display text and value should be consistent between Edit Parameter Dialog in Layout and Parameter dialog during preview.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ParameterDialog.java
if ( DesignChoiceConstants.PARAM_CONTROL_CHECK_BOX.equals( getSelectedControlType( ) ) )
			{
				if ( isValidValue( defaultValue ) != null )
				{
					defaultValue = null;
					defaultValueChooser.select( 0 );
				}
				else
				{
					if ( Boolean.valueOf( defaultValue ).booleanValue( ) )
					{
						defaultValueChooser.select( 1 );
					}
					else
					{
						defaultValueChooser.select( 2 );
					}
				}
			}
			else
			{
				if ( DesignChoiceConstants.PARAM_CONTROL_TEXT_BOX.equals( getSelectedControlType( ) )
						&& defaultValue != null )
				{
					defaultValueEditor.setText( defaultValue );
				}
			}
			refreshValueTable( );
		}
		else