init

jj_vision/interface/fields/comparable_field.e

@@ -0,0 +1,49 @@
+note
+	description: "[
+		A {FIELD} used to create a control to edit a COMPARABLE.
+		]"
+	date: "24 Feb 04"
+	author:		"Jimmy J. Johnson"
+	copyright:	"Copyright 2012, Jimmy J. Johnson"
+	license:	"Eiffel Forum License v2 (see forum.txt)"
+	URL: 		"$URL: file:///F:/eiffel_repositories/jj_vision/trunk/interface/fields/comparable_field.e $"
+	date:		"$Date: 2012-03-16 14:05:07 -0400 (Fri, 16 Mar 2012) $"
+	revision:	"$Revision: 7 $"
+
+
+deferred class
+	COMPARABLE_FIELD
+
+inherit
+
+	FIELD
+		redefine
+			default_create,
+			as_widget,
+			Type
+		end
+
+feature {NONE} -- Initialization
+
+	default_create
+			-- Initialize `Current'.
+		do
+			Precursor {FIELD}
+		end
+
+feature -- Transformation
+
+	as_widget: COMPARABLE_CONTROL
+			-- Each descendent class must create the appropriate control.
+			-- Redefined to change the type.
+		deferred
+		end
+
+feature --
+
+	Type: COMPARABLE
+			-- Anchor for `value'
+		deferred
+		end
+
+end

jj_vision/interface/fields/field.e

@@ -0,0 +1,483 @@
+note
+	description: "[
+			Used with {EDITOR} classes.
+			Object that describes how to create a {CONTROL}.
+			]"
+	date: "7 Mar 03"
+	author:		"Jimmy J. Johnson"
+	copyright:	"Copyright 2012, Jimmy J. Johnson"
+	license:	"Eiffel Forum License v2 (see forum.txt)"
+	URL: 		"$URL: file:///F:/eiffel_repositories/jj_vision/trunk/interface/fields/field.e $"
+	date:		"$Date: 2012-03-16 14:05:07 -0400 (Fri, 16 Mar 2012) $"
+	revision:	"$Revision: 7 $"
+
+
+deferred class
+	FIELD
+
+inherit
+
+	FIELD_CONSTANTS
+		undefine
+			default_create,
+			is_equal
+		end
+
+	EDITABLE
+		redefine
+			default_create,
+			schema,
+			is_schema_available,
+			schema_imp,
+			set_schema,
+			remove_schema
+		end
+
+feature {NONE} -- Initialization
+
+	default_create
+			-- Initialize the object.
+		do
+			Precursor {EDITABLE}
+--			schema_imp := Field_schema
+				-- Add the "data".  The data is the lables and positions.
+			set_label (Default_label_field_name)
+			set_x (Default_x)
+			set_y (Default_y)
+			set_width (Default_width)
+			set_height (Default_height)
+		end
+
+feature -- Access
+
+	schema: FIELD_SCHEMA
+			-- The schema used to display and edit a FIELD.
+		once
+			create Result
+			Result.extend_mandatory (Label_field)
+			Result.extend_mandatory (X_field)
+			Result.extend_mandatory (Y_field)
+			Result.extend_mandatory (Width_field)
+			Result.extend_mandatory (Height_field)
+--			Result.set_up
+		end
+
+	Type: ANY
+			-- Anchor.
+		deferred
+		end
+
+	label: STRING_32
+			-- Identifier of this field.
+		do
+			check attached {STRING_32} value (Default_label_field_name) as s then
+				Result := s
+			end
+		end
+
+	x: INTEGER_REF
+			-- x-position of field in a dialog
+		do
+			check attached {INTEGER_REF} value (Default_x_field_name) as i then
+				Result := i
+			end
+		end
+
+	y: INTEGER_REF
+			-- y-position of field in a dialog
+		do
+			check attached {INTEGER_REF} value (Default_y_field_name) as i then
+				Result := i
+			end
+		end
+
+	width: INTEGER_REF
+			-- Width of this field.  Used to create a control
+			-- that is `width' pixels wide.
+		do
+			check attached {INTEGER_REF} value (Default_width_field_name) as i then
+				Result := i
+			end
+		end
+
+	height: INTEGER_REF
+			-- Height of this field.  Used to create a control
+			-- that is `height' pixels tall.
+		do
+			check attached {INTEGER_REF} value (Default_height_field_name) as i then
+				Result := i
+			end
+		end
+
+--	format: STRING is
+--			-- Used to set how the data is displayed.
+--		do
+--			Result ?= value_by_field (format_field)
+--		ensure
+--			valid_result: Result /= Void
+--		end
+--
+--	posible_formats: LINKED_SET [STRING]
+--			-- Set of posible formats which can be used in `format'.
+--
+--	function: STRING_32
+--			-- Function to be assigned to any widget created from
+--			-- this field.
+--		do
+--			Result ?= value_by_field (schema.formula_field)
+--		ensure
+--			valid_result: Result /= Void
+--		end
+
+--	function_result_as_string: STRING_32
+--			-- The result of executing the `function' converted to
+--			-- a string.
+--		local
+----			p: FUNCTION_PARSER
+--			r: ANY
+--			t: like Type
+--		do
+--			if function = Void then
+--				Result := "Value is calculated, but no formula entered."
+--			else
+----				p.parse_string (function)
+----				r := parser.last_value
+--				if r.same_type (Type) then
+--					t ?= r
+--					check
+--						should_not_happen: t /= Void
+--							-- Because `r.same_type' insures `r' conforms to `t'.
+--					end
+--					Result := type_to_string (t)
+--				else
+--						-- there was a parse error.
+--					Result ?= r
+--					check
+--						should_not_happen: Result /= Void
+--							-- Because parser should return an error string
+--							-- if it failed to get a good result.
+--					end
+--				end
+--			end
+--		end
+
+--	function_result_as_type: like type
+--			-- The result of executing the `function'.
+--		require
+--			has_function: function /= Void
+--			function_works: is_valid_function (function)
+--		local
+----			p: FUNCTION_PARSER
+--		do
+----			p.parse_string (function)
+----			Result := p.last_value
+--		end
+
+feature -- Element Change
+
+	set_label (a_string: STRING_32)
+			-- Change the `name'.
+		require
+			string_exists: a_string /= Void
+		do
+			extend_value (a_string, Default_label_field_name)
+		ensure
+			id_was_set: equal (label, a_string)
+		end
+
+	set_x (a_x: INTEGER)
+		do
+			extend_value (a_x, Default_x_field_name)
+		ensure
+			x_was_set: x.item = a_x
+		end
+
+	set_y (a_y: INTEGER)
+		do
+			extend_value (a_y, Default_y_field_name)
+		ensure
+			y_was_set: y.item = a_y
+		end
+
+	set_width (a_width: INTEGER)
+			-- Change `width'
+		require
+			valid_width: a_width > 0
+		do
+			extend_value (a_width, Default_width_field_name)
+		ensure
+			width_was_set: width.item = a_width
+		end
+
+	set_height (a_height: INTEGER)
+			-- Change `height'
+		require
+			valid_height: a_height > 0
+		do
+			extend_value (a_height, Default_height_field_name)
+		ensure
+			height_was_set: height.item = a_height
+		end
+
+--	set_format (a_format: STRING) is
+--			-- Change `format'
+--		require
+--			schema_exists: schema /= Void
+--			valid_format: posible_formats.has (a_format)
+--		do
+--			extend_with_field (a_format, format_field)
+--			extend (a_format, "format")
+--		ensure
+--			format_was_set: format = a_format
+--		end
+
+--	set_function (a_string: STRING) is
+--			-- Change the `formula'
+--		require
+--			schema_exists: schema /= Void
+--			string_exists: a_string /= Void
+--		do
+--			extend_with_field (a_string, schema.formula_field)
+--		ensure
+--			formula_was_set: equal (formula, a_string)
+--		end
+
+feature -- Status report
+
+	is_calculated: BOOLEAN
+			-- Should the value (produced by any control) use the result
+			-- of executing (parsing) the `formula'?  (Oposite is to use
+			-- what ever data is set into the control.)
+-- fix		-- Set by `use_formula' or `use_data'.
+		do
+--			Result := formula.count >= 1
+		end
+
+	is_schema_available: BOOLEAN
+			-- Does Current have a schema?
+			-- Redefined to always be True to follow the redefinition of `schema'.
+		do
+			Result := True
+		end
+
+feature -- Status setting
+
+	use_function
+			-- Set `is_calculated' to True
+		do
+--			is_calculated := True
+		end
+
+	use_data
+			-- Set `is_calculated' to False
+		do
+--			is_calculated := False
+		end
+
+feature -- Query
+
+--	parser: PARSER is
+--			-- Parser for evaluating the `formula'
+--		once
+--			create Result
+--		end
+
+	is_valid_data (a_value: ANY): BOOLEAN
+			-- Is `a_value' valid data for this field?
+			-- Must redefine `parsed' if redefine this feature.
+		do
+			Result := a_value /= Void and then a_value.conforms_to (Type)
+		end
+
+	is_valid_function (a_function: STRING_32): BOOLEAN
+			-- Can `a_function' be parsed, returning a result
+			-- of the correct `type'?
+		local
+--			p: FUNCTION_PARSER
+		do
+--			p.parse_string (a_function)
+--			Result :=  p.last_value.same_type (type)
+		end
+
+	string_to_type (a_string: STRING_32): like Type
+			-- Convert `a_string' to an object of `Type'
+			-- Default is to simply return `a_string' since
+			-- it conforms to ANY if it exists.
+		require
+			valid_string: is_valid_data (a_string)
+		do
+			Result := a_string
+		end
+
+	type_to_string (a_value: ANY): STRING_32
+			-- The string representation of `a_value'.
+			-- The default is to call feature `out' on `a_value' or to
+			-- return the string "Void" or "Non-conforming data".
+		do
+			if a_value = Void then
+				Result := "Void"
+			elseif a_value /= Void and then not a_value.conforms_to (Type) then
+				Result := "Non-conforming data"
+			else
+				Result := a_value.out
+			end
+		ensure
+			result_exists: Result /= Void
+		end
+
+	controls_from: LINKED_LIST [CONTROL]
+			-- All the controls whose positioning is dictated by
+			-- this field (i.e. created from this field)
+		local
+			c_list: LINKED_LIST [CONTROL]
+			c: CONTROL
+		do
+			create Result.make
+			c_list := control_list
+			from c_list.start
+			until c_list.exhausted
+			loop
+				c := c_list.item
+				if c.field = Current then -- or c.field.formula.has_field (Current) then
+-- make a formula class and put parser in it.				
+					Result.extend (c)
+				end
+				c_list.forth
+			end
+		end
+
+	controls_dependent: LINKED_LIST [CONTROL]
+			-- All the controls in `controls_from' plus any controls
+			-- whose `formula' contains a reference to Current.
+		local
+			c_list: LINKED_LIST [CONTROL]
+			c: CONTROL
+		do
+			create Result.make
+			c_list := control_list
+			from c_list.start
+			until c_list.exhausted
+			loop
+				c := c_list.item
+				if c.field = Current then -- or c.field.formula.has_field (Current) then
+-- make a formula class and put parser in it.				
+					Result.extend (c)
+				end
+				c_list.forth
+			end
+		end
+
+
+feature -- Transformation
+
+	as_widget: CONTROL
+			-- Each descendent class must create the appropriate control and
+			-- put the control into `control_list'.
+		deferred
+		ensure
+			result_has_field: Result.field = Current
+			result_added_to_list: control_list.has (Result)
+		end
+
+feature {CONTROL} -- Implementation
+
+	control_list: LINKED_LIST [CONTROL]
+			-- Keeps track of all the controls so one control can update
+			-- others and used to make formulas work.
+			-- NOTE:  This can be a once feature here as these are only valid
+			-- for the current execution.
+			-- The creation procedures for CONTROL should add the created
+			-- widget to the list; `destroy' from CONTROL should remove it.
+			-- Declared as once function so the list (of EV_WIDGETs) does
+			-- not get stored.  That could get messy.
+		once
+			create Result.make
+		end
+
+	schema_imp: FIELD_SCHEMA
+			-- Implementation and/or anchor for `schema'. Set by `set_schema' and
+			-- removed by `remove_schema.
+			-- NOTE:  The FIELDs in a SCHEMA will determine the keys to be
+			-- used in `data_table' and will be used to build the controls
+			-- for obtaining the values asscociated with the keys.
+
+feature {NONE} -- Implementation (fields used by `field_schema')
+
+	Label_field: STRING_FIELD
+			-- Create a field to store the `label' of a FIELD
+		once
+			create Result
+--			Result.extend (Default_name, Default_label_field_name)
+			Result.set_label (Default_label_field_name)
+			Result.set_x (0)
+			Result.set_y (0)
+			Result.set_width (Default_width)
+			Result.set_height (Default_height)
+		end
+
+	X_field: INTEGER_FIELD
+			-- Create a field to store the `x' value of a FIELD
+		once
+			create Result
+--			Result.extend (Default_x_field_name, Default_x_field_name)
+			Result.set_label (Default_x_field_name)
+			Result.set_x (0)
+			Result.set_y (50)
+			Result.set_width (Default_width)
+			Result.set_height (Default_height)
+		end
+
+	Y_field: INTEGER_FIELD
+			-- Create a field to store the `y' value of a FIELD
+		once
+			create Result
+			Result.set_label (Default_y_field_name)
+			Result.set_x (0)
+			Result.set_y (100)
+			Result.set_width (Default_width)
+			Result.set_height (Default_height)
+		end
+
+	Width_field: INTEGER_FIELD
+			-- Create a field to store the `width' of a FIELD
+		once
+			create Result
+			Result.set_label (Default_width_field_name)
+			Result.set_x (0)
+			Result.set_y (150)
+			Result.set_width (Default_width)
+			Result.set_height (Default_height)
+		end
+
+	Height_field: INTEGER_FIELD
+			-- Create a field to store the `height' of a FIELD
+		once
+			create Result
+			Result.set_label (Default_height_field_name)
+			Result.set_x (0)
+			Result.set_y (200)
+			Result.set_width (Default_width)
+			Result.set_height (Default_height)
+		end
+
+feature {NONE} -- Inaplicable
+
+	set_schema (a_schema: like schema_imp)
+			-- Change `schema' indirectly by changing `schema_imp'.
+		do
+			check
+				should_not_be_called: False
+					-- Because `schema' was redefined to a constant
+			end
+		end
+
+	remove_schema
+			-- Make `schema' imp Void
+		do
+			check
+				should_not_be_called: False
+					-- Because `schema' was redefined to a constant
+			end
+		end
+
+end

jj_vision/interface/fields/field_constants.e

@@ -0,0 +1,32 @@
+note
+	description: "[
+		Constants for use by classes dealing with class {FIELD} (i.e {FIELD} 
+		and {SCHEMA} and any descendants.
+		]"
+	date: "28 Feb 04"
+	author:		"Jimmy J. Johnson"
+	copyright:	"Copyright 2012, Jimmy J. Johnson"
+	license:	"Eiffel Forum License v2 (see forum.txt)"
+	URL: 		"$URL: file:///F:/eiffel_repositories/jj_vision/trunk/interface/fields/field_constants.e $"
+	date:		"$Date: 2012-03-16 14:05:07 -0400 (Fri, 16 Mar 2012) $"
+	revision:	"$Revision: 7 $"
+
+
+class
+	FIELD_CONSTANTS
+
+feature -- Access
+
+	Default_label_field_name: STRING = "label"
+	Default_x_field_name: STRING = "x"
+	Default_y_field_name: STRING = "y"
+	Default_height_field_name: STRING = "height"
+	Default_width_field_name: STRING = "width"
+
+	Default_name: STRING = "name: "
+	Default_x: INTEGER = 0
+	Default_y: INTEGER = 0
+	Default_height: INTEGER = 30
+	Default_width: INTEGER = 150
+
+end

jj_vision/interface/fields/field_ref.e

@@ -0,0 +1,33 @@
+note
+	description: "[
+		A reference to a {FIELD} for use by once feature
+		`user_identifier_field' from {SCHEMA}
+		]"
+	date: "7 Oct 07"
+	author:		"Jimmy J. Johnson"
+	copyright:	"Copyright 2012, Jimmy J. Johnson"
+	license:	"Eiffel Forum License v2 (see forum.txt)"
+	URL: 		"$URL: file:///F:/eiffel_repositories/jj_vision/trunk/interface/fields/field_ref.e $"
+	date:		"$Date: 2012-03-16 14:05:07 -0400 (Fri, 16 Mar 2012) $"
+	revision:	"$Revision: 7 $"
+	
+class
+	FIELD_REF
+
+create
+	set_field
+
+feature -- Access
+
+	field: FIELD
+		-- Item held by current
+
+feature -- Element change
+
+	set_field (a_field: FIELD)
+			-- Change the `field'.
+		do
+			field := a_field
+		end
+
+end

jj_vision/interface/fields/field_schema.e

@@ -0,0 +1,24 @@
+note
+	description: "[
+		A {SCHEMA} for a {FIELD}
+		]"
+	author:		"Jimmy J. Johnson"
+	copyright:	"Copyright 2012, Jimmy J. Johnson"
+	license:	"Eiffel Forum License v2 (see forum.txt)"
+	URL: 		"$URL: file:///F:/eiffel_repositories/jj_vision/trunk/interface/fields/field_schema.e $"
+	date:		"$Date: 2012-03-16 14:05:07 -0400 (Fri, 16 Mar 2012) $"
+	revision:	"$Revision: 7 $"
+
+class
+	FIELD_SCHEMA
+
+inherit
+
+	SCHEMA
+
+create
+	default_create
+create {LINKED_LIST}
+	make
+
+end

jj_vision/interface/fields/formula_field.e

@@ -0,0 +1,42 @@
+note
+	description: "[
+		A {FIELD} in which to edit formulas
+		]"
+	author:		"Jimmy J. Johnson"
+	copyright:	"Copyright 2012, Jimmy J. Johnson"
+	license:	"Eiffel Forum License v2 (see forum.txt)"
+	URL: 		"$URL: file:///F:/eiffel_repositories/jj_vision/trunk/interface/fields/formula_field.e $"
+	date:		"$Date: 2012-03-16 14:05:07 -0400 (Fri, 16 Mar 2012) $"
+	revision:	"$Revision: 7 $"
+
+class FORMULA_FIELD
+	-- creates an edit box.
+
+inherit
+
+	STRING_FIELD
+		redefine
+			is_valid_data
+		end
+
+create
+	default_create
+
+feature -- Access
+
+	is_valid_data (a_data: ANY): BOOLEAN
+			-- Is the value in `a_data' a valid representation
+			-- for the `Type' of the data.
+		local
+--			scan: SCANNER
+--			s: STRING
+		do
+----			create scan
+--			s ?= a_data
+--			if s /= Void then
+----				scan.scan_string (s)
+--			end
+----			Result := Precursor {STRING_FIELD} (a_data) and then not scan.scanning_error
+		end
+
+end

jj_vision/interface/fields/integer_field.e

@@ -0,0 +1,74 @@
+note
+	description: "[
+		A {FIELD} used to create a {INTEGER_CONTROL} and position that control.
+		]"
+	date: "24 Feb 04"
+	author:		"Jimmy J. Johnson"
+	copyright:	"Copyright 2012, Jimmy J. Johnson"
+	license:	"Eiffel Forum License v2 (see forum.txt)"
+	URL: 		"$URL: file:///F:/eiffel_repositories/jj_vision/trunk/interface/fields/integer_field.e $"
+	date:		"$Date: 2012-03-16 14:05:07 -0400 (Fri, 16 Mar 2012) $"
+	revision:	"$Revision: 7 $"
+
+class
+	INTEGER_FIELD
+
+inherit
+
+	COMPARABLE_FIELD
+		redefine
+			default_create,
+			is_valid_data,
+			string_to_type
+		end
+
+create
+	default_create
+
+feature {NONE} -- Initialization
+
+	default_create
+			-- Create an instance
+		do
+			Precursor {COMPARABLE_FIELD}
+		end
+
+feature -- Querry
+
+	Type: INTEGER_REF
+			-- Implementation (and anchor) of `value'.
+			-- Redefined to change type.
+		once
+			create Result
+		end
+
+	string_to_type (a_string: STRING_32): like type
+			-- Convert `a_string' to an object of `Type'.
+		do
+			create Result
+			Result.set_item (a_string.to_integer)
+		end
+
+	is_valid_data (a_value: ANY): BOOLEAN
+			-- Is the value in the display a valid representation
+			-- for the type of the data.
+		do
+			Result := Precursor {COMPARABLE_FIELD} (a_value)
+			if not Result then
+					-- It may be that `a_value' is a STRING representation
+					-- of an integer, so check the string and convert it.
+				if attached {STRING} a_value as s then
+					Result := s.is_integer
+				end
+			end
+		end
+
+feature -- Transformation
+
+	as_widget: INTEGER_CONTROL
+			-- Create the appropriate type of control
+		do
+			create Result.make_from_field (Current)
+		end
+
+end

jj_vision/interface/fields/schema.e

@@ -0,0 +1,444 @@
+note
+	description: "[
+		A list of {FIELD} where each {FIELD} describes the placement
+		of a {CONTROL} withing an {EDITOR}
+		]"
+	author:		"Jimmy J. Johnson"
+	copyright:	"Copyright 2012, Jimmy J. Johnson"
+	license:	"Eiffel Forum License v2 (see forum.txt)"
+	URL: 		"$URL: file:///F:/eiffel_repositories/jj_vision/trunk/interface/fields/schema.e $"
+	date:		"$Date: 2012-03-16 14:05:07 -0400 (Fri, 16 Mar 2012) $"
+	revision:	"$Revision: 7 $"
+
+class
+	SCHEMA
+
+inherit
+
+	LINKED_LIST [FIELD]
+		rename
+			item as field
+		redefine
+			default_create,
+			make,
+			copy,
+			is_equal,
+				-- Redefine the following in order to set the time the schema was
+				-- changed so the dialog editor can use it to determine if it needs
+				-- to redraw the view.
+			extend,
+			put_front,
+			put_left,
+			put_right,
+			merge_left,
+			merge_right,
+				-- Need to redefine the following in order to preserve the invariant
+				-- dealing with the keys (key fields must reside in current).  If a
+				-- field is removed from Current it can no longer be used as a key.
+				-- Other features are defined in terms of this, so these four should
+				-- take care of all features from LINKED_LIST.
+			remove,
+			replace,
+			remove_right,
+			wipe_out
+		select
+			make
+		end
+
+	LINKED_LIST [FIELD]			-- inherited identically as above except for `make'
+		rename
+			make as list_make,
+			item as field
+		redefine
+			default_create,
+--			make,
+			copy,
+			is_equal,
+				-- Redefine the following in order to set the time the schema was
+				-- changed so the dialog editor can use it to determine if it needs
+				-- to redraw the view.
+			extend,
+			put_front,
+			put_left,
+			put_right,
+			merge_left,
+			merge_right,
+				-- Need to redefine the following in order to preserve the invariant
+				-- dealing with the keys (key fields must reside in current).  If a
+				-- field is removed from Current it can no longer be used as a key.
+				-- Other features are defined in terms of this, so these four should
+				-- take care of all features from LINKED_LIST.
+			remove,
+			replace,
+			remove_right,
+			wipe_out
+		end
+
+	EDITABLE
+		redefine
+			default_create,
+			copy,
+			is_equal
+		end
+
+create
+	default_create
+create {LINKED_LIST}
+	make
+
+feature {NONE} -- Initialization
+
+	default_create
+			-- Create an instance
+			-- Redefined because `new_chain' from LINKED_LIST uses `make'.
+		do
+			list_make
+			Precursor {EDITABLE}
+			create keys_imp.make
+			create mandatory_fields.make
+			create time_modified.set_now_utc_fine
+			extend_mandatory (Name_field)
+		end
+
+	make
+			-- Called by `new_chain' from LINKED_LIST
+		do
+			Precursor {LINKED_LIST}
+			default_create
+		end
+
+feature -- Access
+
+	identifying_field: FIELD
+			-- The field used to get a string which will identify an object.
+		do
+			Result := identifying_field_ref.field
+		end
+
+	keys: LINKED_SET [STRING]
+			-- The keys to use in comparison of EDITABLEs using Current.
+			-- NOTE:  Even though FIELDs are used in `keys_imp', ultimately the label
+			-- of the FIELD will be used to access data in an EDITABLE, hence the result type.
+		do
+			create Result.make
+			from keys_imp.start
+			until keys_imp.exhausted
+			loop
+				Result.extend (keys_imp.item.label)
+				keys_imp.forth
+			end
+		end
+
+	key_fields: LINKED_SET [FIELD]
+			-- The fields which are used as keys
+		do
+			create Result.make
+			from keys_imp.start
+			until keys_imp.exhausted
+			loop
+				Result.extend (keys_imp.item)
+				keys_imp.forth
+			end
+		end
+
+	Name_field: STRING_FIELD
+			-- The FIELD used to access the "name" of the object.
+		once
+			create Result
+			Result.set_label ("Name: ")
+		end
+
+	time_modified: YMDHMS_TIME
+			-- Time at which a modification was made (such as adding
+			-- or removing a field).
+
+feature -- Element change
+
+	set_identifying_field (a_field: STRING_FIELD)
+			-- Change the `user_identifying_field'
+		require
+			field_exists: a_field /= Void
+		do
+			identifying_field_ref.set_field (a_field)
+		ensure
+			field_was_assigned: identifying_field = a_field
+		end
+
+feature -- Basic operations
+
+	put_front (a_field: like field)
+			-- Add `a_field' to beginning.
+			-- Do not move cursor.
+			-- Reset `time_modified'.
+		do
+			Precursor {LINKED_LIST} (a_field)
+			time_modified.set_now_utc_fine
+		end
+
+	extend (a_field: like field)
+			-- Add `a_field' to the end.
+			-- Do not move cursor.
+			-- Reset `time_modified'.
+		do
+			Precursor {LINKED_LIST} (a_field)
+			time_modified.set_now_utc_fine
+		end
+
+	extend_mandatory (a_field: like field)
+			-- Add `a_field' to Current and make it a manditory field.
+			-- Reset `time_modified'.
+		require
+			is_extendible: extendible
+		do
+			check
+				field_exists: a_field /= Void
+			end
+			mandatory_fields.extend (a_field)
+			extend (a_field)
+		ensure
+			has_field: has (a_field)
+			has_as_mandatory: has_mandatory (a_field)
+		end
+
+	put_left (a_field: like field)
+			-- Add `a_field' to the left of cursor position.
+			-- Do not move cursor.
+			-- Reset `time_modified'.
+		do
+			Precursor {LINKED_LIST} (a_field)
+			time_modified.set_now_utc_fine
+		end
+
+	put_right (a_field: like field)
+			-- Add `a_field' to the left of cursor position.
+			-- Do not move cursor.
+			-- Reset `time_modified'.
+		do
+			Precursor {LINKED_LIST} (a_field)
+			time_modified.set_now_utc_fine
+		end
+
+	merge_left (a_other: like Current)
+			-- Merge `a_other' into current structure before cursor
+			-- position. Do not move cursor. Empty `other'.
+			-- Reset `time_modified'.
+		do
+			Precursor {LINKED_LIST} (a_other)
+			time_modified.set_now_utc_fine
+		end
+
+	merge_right (a_other: like Current)
+			-- Merge `a_other' into current structure after cursor
+			-- position. Do not move cursor. Empty `other'.
+			-- Reset `time_modified'.
+		do
+			Precursor {LINKED_LIST} (a_other)
+			time_modified.set_now_utc_fine
+		end
+
+	remove
+			-- Remove current item.
+			-- Move cursor to right neighbor
+			-- (or `after' if no right neighbor).
+			-- Reset `time_modified'.
+			-- Also, redefined to preserve invariant.
+		do
+			if attached {COMPARABLE_FIELD} field as cf then
+				keys_imp.prune (cf)
+			else
+				-- Do not have to worry about it, because if `v' is not
+				-- a COMPARABLE_FIELD it would never be in `keys' anyway.
+			end
+			Precursor {LINKED_LIST}
+			time_modified.set_now_utc_fine
+		end
+
+	replace (v: like field)
+			-- Replace current item by `v'.
+			-- Reset `time_modified'.
+			-- Also, redefined to preserve invariant.
+		do
+			if attached {COMPARABLE_FIELD} v as cf then
+				keys_imp.prune (cf)
+			else
+				-- Do not have to worry about it, because if `v' is not
+				-- a COMPARABLE_FIELD it would never be in `keys' anyway.
+			end
+			Precursor {LINKED_LIST} (v)
+			time_modified.set_now_utc_fine
+		end
+
+	remove_right
+			-- Remove item to the right of cursor position.
+			-- Do not move cursor.
+			-- Reset `time_modified'.
+			-- Also, redefined to preserve invariant.
+		do
+			if attached {COMPARABLE_FIELD} i_th (index + 1) as cf then
+				keys_imp.prune (cf)
+			else
+				-- Do not have to worry about it, because if `v' is not
+				-- a COMPARABLE_FIELD it would never be in `keys' anyway.
+			end
+			Precursor {LINKED_LIST}
+			time_modified.set_now_utc_fine
+		end
+
+	wipe_out
+			-- Remove all items.
+			-- Reset `time_modified'.
+			-- Also, redefined to preserve invariant.
+		do
+			keys_imp.wipe_out
+			Precursor {LINKED_LIST}
+			time_modified.set_now_utc_fine
+		end
+
+	add_key_field (a_field: COMPARABLE_FIELD)
+			-- Add `a_field' to use in comparisons
+		require
+			field_exists: a_field /= Void
+			has_field: has (a_field)
+		do
+			keys_imp.extend (a_field)
+		ensure
+			has_key: keys_imp.has (a_field)
+		end
+
+	prune_key_field (a_field: COMPARABLE_FIELD)
+			-- Remove `a_field' so it no longer is used in comparisons
+		require
+			field_exists: a_field /= Void
+		do
+			keys_imp.prune (a_field)
+		ensure
+			removed: not keys_imp.has (a_field)
+		end
+
+	promote_key_field (a_field: COMPARABLE_FIELD)
+			-- Move `a_field' toward the beginning of `keys' by one, so it
+			-- will be a "more important" key.
+		require
+			field_exists: a_field /= Void
+			has_as_key: key_fields.has (a_field)
+		local
+			i: INTEGER
+		do
+			if keys_imp.count > 1 then
+				i := keys_imp.index_of (a_field, 1)
+				if i > 1 then
+					go_i_th (i - 1)
+					swap (i)
+				end
+			end
+		ensure
+			field_was_promoted:
+		end
+
+	demote_key_field (a_field: COMPARABLE_FIELD)
+			-- Move `a_field' toward the end of `keys' by one, so it
+			-- will be a "less important" key.
+		require
+			field_exists: a_field /= Void
+			has_as_key: key_fields.has (a_field)
+		local
+			i: INTEGER
+		do
+			if keys_imp.count > 1 then
+				i := keys_imp.index_of (a_field, 1)
+				if i < count then
+					go_i_th (i + 1)
+					swap (i)
+				end
+			end
+		ensure
+			field_was_demoted:
+		end
+
+	set_key_primary (a_field: COMPARABLE_FIELD)
+			-- Move `a_field' toward the end of `keys' by one, so it
+			-- will be a "less important" key.
+		require
+			field_exists: a_field /= Void
+			has_as_key: key_fields.has (a_field)
+		local
+			i: INTEGER
+		do
+			if keys_imp.count > 1 then
+				i := keys_imp.index_of (a_field, 1)
+				if i /= 1 then
+					go_i_th (1)
+					swap (i)
+				end
+			end
+		ensure
+			field_is_primary: key_fields.index_of (a_field, 1) = 1
+		end
+
+feature -- Querry
+
+	has_mandatory (a_field: like field): BOOLEAN
+			-- Is `a_field' required to always be in this schema?
+			-- (I.e. can it never be deleted?)
+		require
+			field_exists: a_field /= Void
+		do
+			Result := mandatory_fields.has (a_field)
+		ensure
+			definition: Result = mandatory_fields.has (a_field)
+		end
+
+feature  -- Duplication
+
+	copy (other: like Current)
+			-- Update current object using fields of object attached
+			-- to `other', so as to yield equal objects.
+			-- Redefined to merge the copy operations from both ancestors.
+			-- NOTE:  Feature `infix "<"' from VIEWABLE only checks the `id'
+			-- and assumes if the `id' (and hence the `time_stamp' from both
+			-- objects are equal the object must have been copied and is
+			-- therefore equal.
+		do
+			Precursor {LINKED_LIST} (other)
+			Precursor {EDITABLE} (other)
+		end
+
+feature -- Comparison
+
+	is_equal (other: like Current): BOOLEAN
+			-- Is Current equal to `other'?
+		do
+				-- Precursor {VIEWABLE} uses feature `infix "<"' to do the
+				-- comparison, and there is no less than feature in LINKED_LIST,
+				-- therefore this feature makes the BIG assumption that if
+				-- the `id' and `time_stamp' (from VIEWABLE) of both objects
+				-- are the same then it must have been a copy.  There is no other
+				-- way to make the `time_stamps' equal.
+			Result := Precursor {EDITABLE} (other)
+		end
+
+feature {NONE} -- Implementation
+
+	keys_imp: LINKED_SET [COMPARABLE_FIELD]
+			-- Set of fields whose associated values can be used to compare
+			-- one EDITABLE to another in feature `infix "<"' from EDITABLE.
+			-- The order implies the more significant fields.
+
+	mandatory_fields: LINKED_SET [FIELD]
+			-- Set of fields which can not be deleted from Current.
+
+	identifying_field_ref: FIELD_REF
+			-- The field to be used as `identifying_field' as set by the user
+			-- in place of the default field.
+		once
+			create Result.set_field (Name_field)
+		end
+
+invariant
+
+	keys_imp_exists: keys_imp /= Void
+	manditory_fields_exists: mandatory_fields /= Void
+	keys_reside_in_current: key_fields.for_all (agent has)
+	mandatory_fields_reside_in_current: mandatory_fields.for_all (agent has)
+
+end

jj_vision/interface/fields/string_field.e

@@ -0,0 +1,48 @@
+note
+	description: "[
+		A {FIELD} describing the placement of a {STRING_CONTROL}
+		]"
+	author:		"Jimmy J. Johnson"
+	copyright:	"Copyright 2012, Jimmy J. Johnson"
+	license:	"Eiffel Forum License v2 (see forum.txt)"
+	URL: 		"$URL: file:///F:/eiffel_repositories/jj_vision/trunk/interface/fields/string_field.e $"
+	date:		"$Date: 2012-03-16 14:05:07 -0400 (Fri, 16 Mar 2012) $"
+	revision:	"$Revision: 7 $"
+
+class STRING_FIELD
+	-- creates an edit box.
+
+inherit
+
+	COMPARABLE_FIELD
+
+create
+	default_create
+
+feature {NONE} -- Initialization
+
+feature -- Access
+
+feature -- Querry
+
+	type: STRING_32
+			-- Implementation (and anchor) of `value'.
+			-- Redefined to change type.
+		once
+			create Result.make_from_string ("")
+		end
+
+	as_type (a_string: STRING_32): like type
+			-- Convert `a_string' to an object of `Type'.
+		do
+			Result := a_string
+		end
+
+feature -- Transformation
+
+	as_widget: STRING_CONTROL
+		do
+			create Result.make_from_field (Current)
+		end
+
+end

jj_vision/interface/fields/ymd_time_field.e

@@ -0,0 +1,82 @@
+note
+	description: "[
+		A {FIELD} decribing the placement of a {YMD_TIME_CONTROL}
+		]"
+	author:		"Jimmy J. Johnson"
+	copyright:	"Copyright 2012, Jimmy J. Johnson"
+	license:	"Eiffel Forum License v2 (see forum.txt)"
+	URL: 		"$URL: file:///F:/eiffel_repositories/jj_vision/trunk/interface/fields/ymd_time_field.e $"
+	date:		"$Date: 2012-03-16 14:05:07 -0400 (Fri, 16 Mar 2012) $"
+	revision:	"$Revision: 7 $"
+
+class
+	YMD_TIME_FIELD
+
+inherit
+
+	COMPARABLE_FIELD
+		redefine
+			is_valid_data,
+			string_to_type,
+			type_to_string
+		end
+
+create
+	default_create
+
+feature -- Access
+
+	Type: YMD_TIME
+			-- Implementation (and anchor) of `value'.
+			-- Redefined to change type.
+		once
+			create Result.set_now
+		end
+
+	is_valid_data (a_value: ANY): BOOLEAN
+			-- Is the value in `a_value' a valid representation
+			-- for the `Type' of the data.
+		local
+			f: YMD_TIME_FORMATTER
+		do
+			Result := Precursor {COMPARABLE_FIELD} (a_value)
+			if not Result then
+					-- It may be that `a_value' is a STRING representation
+					-- of a date, so check the string and convert it.
+				create f
+				if attached {STRING} a_value as s then
+					Result := f.is_valid (s)
+				end
+			end
+		end
+
+	string_to_type (a_string: STRING_32): like Type
+			-- Convert `a_string' to a YMD_TIME
+		local
+			f: YMD_TIME_FORMATTER
+		do
+			create f
+			Result := f.to_ymd_time (a_string)
+		end
+
+	type_to_string (a_value: ANY): STRING_32
+			-- The string representation of `a_value'.
+		local
+			f: YMD_TIME_FORMATTER
+		do
+			if attached {YMD_TIME} a_value as t then
+				create f
+				Result := f.to_string (t)
+			else
+				Result := Precursor {COMPARABLE_FIELD} (a_value)
+			end
+		end
+
+feature -- Transformation
+
+	as_widget: YMD_TIME_CONTROL
+		do
+			create Result.make_from_field (Current)
+		end
+
+end