indexing
	description: "Representation of a row of an EV_GRID"
	legal: "See notice at end of class."
	status: "See notice at end of class."
	date: "$Date: 2006-08-30 16:39:03 -0700 (Wed, 30 Aug 2006) $"
	revision: "$Revision: 63152 $"

class interface
	EV_GRID_ROW_I

create 
	make (an_interface: like interface)
			-- Create `Current' with interface `an_interface'.
		require -- from EV_ANY_I
			an_interface_not_void: an_interface /= Void
		ensure -- from EV_ANY_I
			interface_assigned: interface = an_interface
			base_make_called: base_make_called

feature -- Access

	collapse_actions: EV_NOTIFY_ACTION_SEQUENCE
			-- Actions to be performed when `Current' is collapsed.
			-- (from EV_GRID_ROW_ACTION_SEQUENCES_I)
		ensure -- from EV_GRID_ROW_ACTION_SEQUENCES_I
			result_not_void: Result /= Void

	deselect_actions: EV_NOTIFY_ACTION_SEQUENCE
			-- Actions to be performed when `Current' is deselected.
			-- (from EV_GRID_ROW_ACTION_SEQUENCES_I)
		ensure -- from EV_GRID_ROW_ACTION_SEQUENCES_I
			result_not_void: Result /= Void

	expand_actions: EV_NOTIFY_ACTION_SEQUENCE
			-- Actions to be performed when `Current' is expanded.
			-- (from EV_GRID_ROW_ACTION_SEQUENCES_I)
		ensure -- from EV_GRID_ROW_ACTION_SEQUENCES_I
			result_not_void: Result /= Void

	generating_type: STRING_8
			-- Name of current object's generating type
			-- (type of which it is a direct instance)
			-- (from ANY)

	generator: STRING_8
			-- Name of current object's generating class
			-- (base class of the type of which it is a direct instance)
			-- (from ANY)

	has_subrow (a_row: EV_GRID_ROW): BOOLEAN
			-- Is `a_row' a child of Current?
		require
			a_row_not_void: a_row /= Void
			is_parented: parent /= Void
		ensure
			has_subrow_same_parent: Result implies ((a_row.parent /= Void and parent /= Void) and then a_row.parent = parent)

	height: INTEGER_32
			-- Height of `Current' when displayed in a parent
			-- that has `is_row_height_fixed' set to `False'.
			-- Note that height is ignored if the parent has
			-- `is_row_height_fixed' set to `True' and then all rows
			-- are displayed with identical heights set to `parent.row_height'.
		require
			is_parented: parent /= Void
		ensure
			result_not_negative: Result >= 0

	internal_are_all_non_void_items_selected: BOOLEAN
			-- Are all the non void items in `Current' selected?
			-- False if no non void items are present.

	internal_height: INTEGER_32

	internal_is_selected: BOOLEAN
			-- Is `Current' selected in either row selection mode?

	internal_update_selection (a_selection_state: BOOLEAN)
			-- Set the selection state of all non void items in `Current' to `a_selection_state'.

	is_expandable: BOOLEAN
			-- May `Current' be expanded?
		require
			is_parented: parent /= Void

	is_expanded: BOOLEAN
			-- Are subrows of `Current' displayed?

	is_selectable: BOOLEAN
			-- May the object be selected?

	is_selected: BOOLEAN
			-- Is objects state set to selected.

	item (i: INTEGER_32): EV_GRID_ITEM
			-- Item at `i'-th column, Void if none.
		require
			i_within_bounds: i > 0 and i <= count
			is_parented: parent /= Void

	parent: EV_GRID
			-- Grid to which current row belongs.

	parent_row: EV_GRID_ROW
			-- Parent row of Current if any, Void otherwise.
		require
			is_parented: parent /= Void
		ensure
			result_void_when_tree_node_enabled: (parent = Void) or (parent /= Void and then not parent.is_tree_enabled) implies Result = Void
			has_parent: Result /= Void implies Result.has_subrow (interface)

	parent_row_root: EV_GRID_ROW
			-- Parent row which is the root of the tree structure
			-- in which `Current' is contained. May be `Current' if
			-- `Current' is the root node of a tree structure.
		require
			is_parented: parent /= Void
		ensure
			result_consistent_with_parent_tree_properties: (parent = Void or else not parent.is_tree_enabled) = (Result = Void)

	select_actions: EV_NOTIFY_ACTION_SEQUENCE
			-- Actions to be performed when `Current' is selected.
			-- (from EV_GRID_ROW_ACTION_SEQUENCES_I)
		ensure -- from EV_GRID_ROW_ACTION_SEQUENCES_I
			result_not_void: Result /= Void

	selected_items: ARRAYED_LIST [EV_GRID_ITEM]
			-- All items selected in `Current'.
		require
			is_parented: parent /= Void
		ensure
			result_not_void: Result /= Void
			valid_count: Result.count <= count

	subrow (i: INTEGER_32): EV_GRID_ROW
			-- `i'-th child of Current.
		require
			is_parented: parent /= Void
			i_positive: i > 0
			i_less_than_subrow_count: i <= subrow_count
		ensure
			subrow_not_void: Result /= Void
			subrow_valid: (Result.parent /= Void) and then has_subrow (Result) and then Result.parent_row = interface

	virtual_y_position: INTEGER_32
			-- Vertical offset of `Current' in relation to the
			-- the virtual area of parent grid in pixels.
			-- `Result' is 0 if parent is `Void'.
		ensure
			parent_void_implies_result_zero: parent = Void implies Result = 0

	virtual_y_position_unlocked: INTEGER_32
			-- Vertical offset of unlocked position of `Current', in relation to the
			-- virtual area of parent grid in pixels.
			-- If not is_locked, then virtual_y_position = `unlocked_virtual_y_position'.
			-- If is_locked then `Result' is the "shadow" position where the row would
			-- be if not locked.
		ensure
			parent_void_implies_result_zero: parent = Void implies Result = 0
	
feature -- Comparison

	frozen deep_equal (some: ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void
			-- or attached to isomorphic object structures?
			-- (from ANY)
		ensure -- from ANY
			shallow_implies_deep: standard_equal (some, other) implies Result
			both_or_none_void: (some = Void) implies (Result = (other = Void))
			same_type: (Result and (some /= Void)) implies some.same_type (other)
			symmetric: Result implies deep_equal (other, some)

	frozen equal (some: ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void or attached
			-- to objects considered equal?
			-- (from ANY)
		ensure -- from ANY
			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.is_equal (other))

	is_equal (other: like Current): BOOLEAN
			-- Is `other' attached to an object considered
			-- equal to current object?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			symmetric: Result implies other.is_equal (Current)
			consistent: standard_is_equal (other) implies Result

	frozen standard_equal (some: ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void or attached to
			-- field-by-field identical objects of the same type?
			-- Always uses default object comparison criterion.
			-- (from ANY)
		ensure -- from ANY
			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.standard_is_equal (other))

	frozen standard_is_equal (other: like Current): BOOLEAN
			-- Is `other' attached to an object of the same type
			-- as current object, and field-by-field identical to it?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			same_type: Result implies same_type (other)
			symmetric: Result implies other.standard_is_equal (Current)
	
feature -- Status report

	background_color: EV_COLOR
			-- Color displayed as background of `Current' except where there are items contained that
			-- have a non-`Void' background_color. If `Void', background_color of parent is displayed..

	conforms_to (other: ANY): BOOLEAN
			-- Does type of current object conform to type
			-- of `other' (as per Eiffel: The Language, chapter 13)?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void

	count: INTEGER_32
			-- Number of items in current.
		ensure
			count_not_negative: count >= 0

	foreground_color: EV_COLOR
			-- Color displayed for foreground features of `Current' except where there are items contained that
			-- have a non-`Void' foreground_color. If `Void', foreground_color of parent is displayed.

	index: INTEGER_32
			-- Position of Current in parent.

	index_of_first_item: INTEGER_32
			-- Return the index of the first non `Void' item within `Current'
			-- or 0 if none.
		ensure
			valid_result: Result >= 0 and Result <= count
			value_valid: index_of_first_item_internal = index_of_first_item_value

	index_of_first_item_value: INTEGER_32
			-- Return the index of the first non `Void' item within `Current'
			-- or 0 if none.
		ensure
			valid_result: Result >= 0 and Result <= count

	is_hashable: BOOLEAN
			-- May current object be hashed?
			-- (True if it is not its type's default.)
			-- (from HASHABLE)
		ensure -- from HASHABLE
			ok_if_not_default: Result implies (Current /= default)

	is_locked: BOOLEAN
			-- Is `Current' locked so that it no longer scrolls?
			-- Note that this could be implemented as a function
			-- "Result := parent_i.locked_rows.item (index) /= Void" but this has not been done
			-- so for performance reasons.

	locked_position: INTEGER_32
			-- Locked position of `Current' from top edge of viewable area of parent.
			-- `Result' is 0 if not is_locked.
		ensure
			not_locked_implies_result_zero: not is_locked implies Result = 0

	locked_row: EV_GRID_LOCKED_ROW_I
			-- Locked row information for `Current'.
			-- `Void' if not locked.

	same_type (other: ANY): BOOLEAN
			-- Is type of current object identical to type of `other'?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			definition: Result = (conforms_to (other) and other.conforms_to (Current))

	subrow_count: INTEGER_32
			-- Number of children.
		require
			is_parented: parent /= Void
		ensure
			subrow_count_non_negative: subrow_count >= 0
			subrow_count_in_range: subrow_count <= (parent.row_count - index)

	subrow_count_recursive: INTEGER_32
			-- Number of child rows and their child rows recursively.

	subrow_index: INTEGER_32
			-- Position of `Current' in parent_row if any.
	
feature -- Status setting

	collapse
			-- Hide all subrows of `Current'.
		require
			is_parented: parent /= Void
		ensure
			not_is_expanded: not is_expanded
			node_counts_correct: node_counts_correct

	ensure_expandable
			-- Ensure `Current' displays an expand pixmap to simulate a `row_count' greater than 0.
			-- May be used for dynamic behavior by filling subrows upon firing of `grid.row_expand_actions'.
			-- If no items are added to `Current' during the firing of `grid.row_expand_actions' then
			-- `Current' is no longer expandable. This may be re-instated by calling ensure_expandable again
			-- from `grid.row_expand_actions'. Note that once a subrow is added to `Current' after a call to
			-- ensure_expandable, it is no longer be displayed as expandable if all subrows are then removed.
			-- In this case, you must explicitly call ensure_expandable again after removing all subrows.
		require
			parented: parent /= Void
			parent_tree_enabled: parent.is_tree_enabled
		ensure
			is_expandable: is_expandable

	ensure_non_expandable
			-- Restore expanded state of `Current' after a call to ensure_expandable. Note that if a row
			-- has one or more subrows, it is always drawn as expanded, hence the "no_subrows_contained" precondition.
		require
			parented: parent /= Void
			no_subrows_contained: subrow_count = 0
		ensure
			not_is_expandable: not is_expandable

	ensure_visible
			-- Ensure `Current' is visible in viewable area of parent.
		require
			parented: parent /= Void
		ensure
			parent_virtual_x_position_unchanged: old parent.virtual_x_position = parent.virtual_x_position
			to_implement_assertion ("old_is_visible_implies_vertical_position_not_changed")
			row_visible_when_heights_fixed_in_parent: parent.is_row_height_fixed implies virtual_y_position >= parent.virtual_y_position and virtual_y_position + parent.row_height <= parent.virtual_y_position + (parent.viewable_height).max (parent.row_height)
			row_visible_when_heights_not_fixed_in_parent: not parent.is_row_height_fixed implies virtual_y_position >= parent.virtual_y_position and virtual_y_position + height <= parent.virtual_y_position + (parent.viewable_height).max (height)

	expand
			-- Display all subrows of `Current'.
		require
			is_parented: parent /= Void
			is_expandable: is_expandable
		ensure
			is_expanded: is_expanded or subrow_count = 0
			node_counts_correct: node_counts_correct

	hide
			-- Prevent `Current' from being shown in parent.
		require
			parented: parent /= Void

	is_ensured_expandable: BOOLEAN
			-- May current be expanded even through it is empty?

	is_show_requested: BOOLEAN
			-- May `Current' be displayed?
			-- Will return `False' if hide has been called on `Current'.
			-- A row that is_show_requested does not necessarily have to be visible on screen at that particular time.
			-- For example, its parent_row (if any) may not be expanded or visible, or the position of `Current' may not
			-- be within the visible area of parent.

	lock_at_position (a_position: INTEGER_32)
			-- Ensure is_locked is `True' with the vertical offset from
			-- the top edge of the viewable area of parent set to `a_position'.
		ensure
			is_locked: is_locked
			locked_position_set: locked_position = a_position

	redraw
			-- Force all items within `Current' to be re-drawn when next idle.
		require
			parented: parent /= Void

	set_background_color (a_color: EV_COLOR)
			-- Set background_color with `a_color'.
		require
			is_parented: parent /= Void
		ensure
			background_color_set: background_color = a_color

	set_foreground_color (a_color: EV_COLOR)
			-- Set foreground_color with `a_color'.
		require
			is_parented: parent /= Void
		ensure
			foreground_color_set: foreground_color = a_color

	set_height (a_height: INTEGER_32)
			-- Assign `a_height' to height.
		require
			is_parented: parent /= Void
		ensure
			height_set: height = a_height

	show
			-- Ensure `Current' is shown in parent.
		require
			parented: parent /= Void

	unlock
			-- Ensure is_locked is `False'.
		ensure
			not_is_locked: not is_locked
	
feature -- Duplication

	copy (other: like Current)
			-- Update current object using fields of object attached
			-- to `other', so as to yield equal objects.
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
			type_identity: same_type (other)
		ensure -- from ANY
			is_equal: is_equal (other)

	frozen deep_copy (other: like Current)
			-- Effect equivalent to that of:
			--		copy (`other' . deep_twin)
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			deep_equal: deep_equal (Current, other)

	frozen deep_twin: like Current
			-- New object structure recursively duplicated from Current.
			-- (from ANY)
		ensure -- from ANY
			deep_equal: deep_equal (Current, Result)

	frozen standard_copy (other: like Current)
			-- Copy every field of `other' onto corresponding field
			-- of current object.
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
			type_identity: same_type (other)
		ensure -- from ANY
			is_standard_equal: standard_is_equal (other)

	frozen standard_twin: like Current
			-- New object field-by-field identical to `other'.
			-- Always uses default copying semantics.
			-- (from ANY)
		ensure -- from ANY
			standard_twin_not_void: Result /= Void
			equal: standard_equal (Result, Current)

	frozen twin: like Current
			-- New object equal to `Current'
			-- twin calls copy; to change copying/twining semantics, redefine copy.
			-- (from ANY)
		ensure -- from ANY
			twin_not_void: Result /= Void
			is_equal: Result.is_equal (Current)
	
feature -- Basic operations

	frozen default: like Current
			-- Default value of object's type
			-- (from ANY)

	frozen default_pointer: POINTER
			-- Default value of type `POINTER'
			-- (Avoid the need to write `p'.default for
			-- some `p' of type `POINTER'.)
			-- (from ANY)

	default_rescue
			-- Process exception for routines with no Rescue clause.
			-- (Default: do nothing.)
			-- (from ANY)

	frozen do_nothing
			-- Execute a null action.
			-- (from ANY)
	
feature -- Markers

	fixme (comment: STRING_8)
			-- Mark code that has to be "fixed" with `comment'.
			-- (from REFACTORING_HELPER)
		require -- from REFACTORING_HELPER
			comment_not_void: comment /= Void

	to_implement (comment: STRING_8)
			-- Mark code that has to be "implemented" with `comment'.
			-- (from REFACTORING_HELPER)
		require -- from REFACTORING_HELPER
			comment_not_void: comment /= Void

	to_implement_assertion (comment: STRING_8): BOOLEAN
			-- Mark assertion that has to be "implemented" with `comment'.
			-- (from REFACTORING_HELPER)
		require -- from REFACTORING_HELPER
			comment_not_void: comment /= Void
	
feature -- Output

	io: STD_FILES
			-- Handle to standard file setup
			-- (from ANY)

	out: STRING_8
			-- New string containing terse printable representation
			-- of current object
			-- Was declared in ANY as synonym of tagged_out.
			-- (from ANY)

	print (some: ANY)
			-- Write terse external representation of `some'
			-- on standard output.
			-- (from ANY)

	frozen tagged_out: STRING_8
			-- New string containing terse printable representation
			-- of current object
			-- Was declared in ANY as synonym of out.
			-- (from ANY)
	
feature -- Platform

	operating_environment: OPERATING_ENVIRONMENT
			-- Objects available from the operating system
			-- (from ANY)
	
invariant
	no_subrows_implies_not_expanded: parent /= Void and then subrow_count = 0 implies not is_expanded
	subrows_not_void: is_initialized implies subrows /= Void
	hash_code_valid: is_initialized implies ((parent = Void and then hash_code = -1) or else (parent /= Void and then hash_code > 0))

		-- from ANY
	reflexive_equality: standard_is_equal (Current)
	reflexive_conformance: conforms_to (Current)

		-- from EV_ANY_I
	interface_coupled: is_usable implies interface /= Void and then interface.implementation = Current
	base_make_called: base_make_called

indexing
	copyright: "Copyright (c) 1984-2006, Eiffel Software and others"
	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
	source: "[
		Eiffel Software
		356 Storke Road, Goleta, CA 93117 USA
		Telephone 805-685-1006, Fax 805-685-6869
		Website http://www.eiffel.com
		Customer support http://support.eiffel.com
	]"

end -- class EV_GRID_ROW_I