#------------------------------------------------------------------------------- # # An abstract base class implementation of the ITemplateDataNameItem interface # that looks for all specified values in its input context or optionally any of # its sub-contexts and outputs a context containing all such values found. # # Written by: David C. Morrill # # Date: 07/29/2007 # # (c) Copyright 2007 by Enthought, Inc. # #------------------------------------------------------------------------------- """ An abstract base class implementation of the ITemplateDataNameItem interface that looks for all specified values in its input context or optionally any of its sub-contexts and outputs a context containing all such values found. """ #------------------------------------------------------------------------------- # Imports: #------------------------------------------------------------------------------- from traits.api \ import HasPrivateTraits, Instance, Property, implements from apptools.template.template_traits \ import TBool from apptools.template.itemplate_data_context \ import ITemplateDataContext from apptools.template.itemplate_data_name_item \ import ITemplateDataNameItem from apptools.template.template_impl \ import Template from template_data_context \ import TemplateDataContext from helper \ import path_for #------------------------------------------------------------------------------- # 'AnyDataNameItem' class: #------------------------------------------------------------------------------- class AnyDataNameItem ( Template ): """ An abstract base class implementation of the ITemplateDataNameItem interface that looks for all specified values in its input context or optionally any of its sub-contexts and outputs a context containing all such values found. """ implements ( ITemplateDataNameItem ) #-- 'ITemplateDataNameItem' Interface Implementation ----------------------- # The data context which this data name item should match against: input_data_context = Instance( ITemplateDataContext ) # The data context containing the data values and/or contexts this data # name item matches: output_data_context = Instance( ITemplateDataContext ) # The ITemplateChoice instance representing the current settings of the # data name item. This value must be read/write, and must be overridden by # sublasses. data_name_item_choice = Property # The alternative choices the user has for the data name item settings for # the current input data context. The list may be empty, in which case the # user cannot change the settings of the data name item. This value can be # read only, and must be overridden by subclasses. data_name_item_choices = Property #-- Public Traits ---------------------------------------------------------- # Should all sub-contexts be included in the search: recursive = TBool( False ) # Should included sub-contexts be flattened into a single context? flatten = TBool( False ) #-- Private Traits --------------------------------------------------------- # The current recursive setting: current_recursive = TBool( False ) # The current input data context: current_input_data_context = Property #-- Abstract Methods (Must be overridden in subclasses) -------------------- def filter ( self, name, value ): """ Returns **True** if the specified context data *name* and *value* should be included in the output context; and **False** otherwise. """ raise NotImplementedError #-- Property Implementations ----------------------------------------------- def _get_data_name_item_choice ( self ): raise NotImplementedError def _set_data_name_item_choice ( self, value ): raise NotImplementedError def _get_data_name_item_choices ( self ): raise NotImplementedError def _get_current_input_data_context ( self ): return self.input_data_context #-- Trait Event Handlers --------------------------------------------------- def _recursive_changed ( self, value ): """ Handles the primary recursive setting being changed. """ self.current_recursive = value def _input_data_context_changed ( self ): """ Handles the 'input_data_context' trait being changed. """ self.inputs_changed() #-- Private Methods -------------------------------------------------------- def inputs_changed ( self ): """ Handles any input value being changed. This method should be called by subclasses when any of their input values change. """ output_context = None input_context = self.current_input_data_context if input_context is not None: values = {} if self.current_recursive: if self.flatten: self._add_context( input_context, values ) else: self._copy_context( input_context, values ) else: self._add_values( input_context, values, '' ) if len( values ) > 0: output_context = TemplateDataContext( data_context_path = input_context.data_context_path, data_context_name = input_context.data_context_name, values = values ) self.output_data_context = output_context def _add_values ( self, input_context, values, path = '' ): """ Adds all of the matching values in the specified *input_context* to the specified *values* dictionary. """ # Filter each name/value in the current input context to see if it # should be added to the output values: filter = self.filter gdcv = input_context.get_data_context_value for name in input_context.data_context_values: value = gdcv( name ) if self.filter( name, value ): values[ path_for( path, name ) ] = value def _add_context ( self, input_context, values, path = '' ): """ Adds all of the matching values in the specified *input_context* to the specified *output_context*, and then applies itself recursively to all contexts contained in the specified *input_context*. """ # Add all of the filtered values in the specified input context: self._add_values( input_context, values, path ) # Now process all of the input context's sub-contexts: gdc = input_context.get_data_context for name in input_context.data_contexts: self._add_context( gdc( name ), values, path_for( path, input_context.data_context_name ) ) def _copy_context ( self, input_context ): """ Clone the input context so that the result only contains values and contexts which contain valid values and are not empty. """ values = {} contexts = {} # Add all of the filtered values in the specified input context: self._add_values( input_context, values ) # Now process all of the input context's sub-contexts: gdc = input_context.get_data_context for name in input_context.data_contexts: context = self._copy_context( gdc( name ) ) if context is not None: contexts[ name ] = context if (len( values ) == 0) and (len( contexts ) == 0): return None return TemplateDataContext( data_context_path = input_context.data_context_path, data_context_name = input_context.data_context_name, values = values, contexts = contexts )