Bug 177439 Need an easy way to determine default value for a dynamic parameter
Currently, I have to bring up the data set editor, preview the results in the data set and make a mental note of the value to use for a report parameter that depends on a data set. It would be nice to have a drop down on the default value field, such as <Select value> which when selected queries the data set and presents me with a list to select from.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ParameterDialog.java
defaultValue = inputParameter.getDefaultValue( );
		if ( DesignChoiceConstants.PARAM_TYPE_DATETIME.equals( getSelectedDataType( ) ) )
		{
			try
			{
				defaultValue = convertToStandardFormat( DataTypeUtil.toDate( defaultValue ) );
			}
			catch ( BirtException e )
			{
				ExceptionHandler.handle( e );
				return false;
			}
		}
		if ( inputParameter.getPropertyHandle( ScalarParameterHandle.LIST_LIMIT_PROP )
				.isSet( ) )
		{
			listLimit.setText( String.valueOf( inputParameter.getListlimit( ) ) );
		}
		isHidden.setSelection( inputParameter.isHidden( ) );
		
		
		isRequired.setSelection( inputParameter.isRequired( ) );
		doNotEcho.setSelection( inputParameter.isConcealValue( ) );
		needSort.setSelection( !inputParameter.isFixedOrder( ) );
		changeDataType( );
		dataTypeChooser.setText( DATA_TYPE_CHOICE_SET.findChoice( inputParameter.getDataType( ) )
				.getDisplayName( ) );
		switchParamterType( );
		loading = false;
		return true;