indexing
	description: "Objects that represent an EiffelVision2 header item for EV_GRID_COLUMN."
	legal: "See notice at end of class."
	status: "See notice at end of class."
	date: "$Date: 2006-01-31 14:44:41 -0800 (Tue, 31 Jan 2006) $"
	revision: "$Revision: 56811 $"

class interface
	EV_GRID_HEADER_ITEM

create {EV_GRID_COLUMN_I}
	make_with_grid_column (a_column: EV_GRID_COLUMN_I)
			-- Create and associate `Current' with `a_column'
		require
			a_column_not_void: a_column /= Void

feature -- Access

	accept_cursor: EV_POINTER_STYLE
			-- `Result' is cursor displayed when the screen pointer is over a
			-- target that accepts pebble during pick and drop.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from  EV_ABSTRACT_PICK_AND_DROPABLE
			True
		ensure -- from EV_ABSTRACT_PICK_AND_DROPABLE
			result_not_void: Result /= Void
		ensure then -- from EV_PICK_AND_DROPABLE
			bridge_ok: Result = implementation.accept_cursor

	column: EV_GRID_COLUMN_I
			-- Grid column to which `Current' is associated with.

	data: ANY
			-- Arbitrary user data may be stored here.
			-- (from EV_ANY)

	deny_cursor: EV_POINTER_STYLE
			-- `Result' is cursor displayed when the screen pointer is over a
			-- target that does not accept pebble during pick and drop.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from  EV_ABSTRACT_PICK_AND_DROPABLE
			True
		ensure -- from EV_ABSTRACT_PICK_AND_DROPABLE
			result_not_void: Result /= Void
		ensure then -- from EV_PICK_AND_DROPABLE
			bridge_ok: Result = implementation.deny_cursor

	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)

	frozen id_object (an_id: INTEGER_32): IDENTIFIED
			-- Object associated with `an_id' (void if no such object)
			-- (from IDENTIFIED)
		ensure -- from IDENTIFIED
			consistent: Result = Void or else Result.object_id = an_id

	maximum_width: INTEGER_32
			-- Upper bound on width in pixels.
			-- (from EV_HEADER_ITEM)
		require -- from EV_HEADER_ITEM
			not_destroyed: not is_destroyed
		ensure -- from EV_HEADER_ITEM
			bridge_ok: Result = implementation.maximum_width
			positive_or_zero: Result >= 0

	minimum_width: INTEGER_32
			-- Lower bound on width in pixels.
			-- (from EV_HEADER_ITEM)
		require -- from EV_HEADER_ITEM
			not_destroyed: not is_destroyed
		ensure -- from EV_HEADER_ITEM
			bridge_ok: Result = implementation.minimum_width
			positive_or_zero: Result >= 0

	frozen object_id: INTEGER_32
			-- Unique for current object in any given session
			-- (from IDENTIFIED)
		ensure -- from IDENTIFIED
			valid_id: id_object (Result) = Current

	parent: EV_ITEM_LIST [EV_ITEM]
			-- Item list containing `Current'.
			-- (from EV_ITEM)
		require -- from EV_CONTAINABLE
			not_destroyed: not is_destroyed
		ensure then -- from EV_ITEM
			bridge_ok: Result = implementation.parent

	pebble: ANY
			-- Data to be transported by pick and drop mechanism.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from  EV_ABSTRACT_PICK_AND_DROPABLE
			True
		ensure then -- from EV_PICK_AND_DROPABLE
			bridge_ok: Result = implementation.pebble

	pebble_function: FUNCTION [ANY, TUPLE, ANY]
			-- Returns data to be transported by pick and drop mechanism.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from  EV_ABSTRACT_PICK_AND_DROPABLE
			True
		ensure then -- from EV_PICK_AND_DROPABLE
			bridge_ok: Result = implementation.pebble_function

	pebble_positioning_enabled: BOOLEAN
			-- If `True' then pick and drop start coordinates are
			-- pebble_x_position, pebble_y_position.
			-- If `False' then pick and drop start coordinates are
			-- the pointer coordinates.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure then -- from EV_PICK_AND_DROPABLE
			bridge_ok: Result = implementation.pebble_positioning_enabled

	pebble_x_position: INTEGER_32
			-- Initial x position for pick and drop relative to `Current'.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure then -- from EV_PICK_AND_DROPABLE
			bridge_ok: Result = implementation.pebble_x_position

	pebble_y_position: INTEGER_32
			-- Initial y position for pick and drop relative to `Current'.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure then -- from EV_PICK_AND_DROPABLE
			bridge_ok: Result = implementation.pebble_y_position

	pixmap: EV_PIXMAP
			-- Copy of image displayed on `Current'.
			-- Void if none.
			-- (from EV_PIXMAPABLE)
		require -- from EV_PIXMAPABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_PIXMAPABLE
			bridge_ok: (Result = Void and implementation.pixmap = Void) or Result.is_equal (implementation.pixmap)

	target_name: STRING_GENERAL
			-- Optional textual name describing `Current' pick and drop hole.
			-- (from EV_ABSTRACT_PICK_AND_DROPABLE)

	text: STRING_32
			-- Text displayed in textable.
			-- (from EV_TEXTABLE)
		require -- from EV_TEXTABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_TEXTABLE
			bridge_ok: equal (Result, implementation.text)
			not_void: Result /= Void
			cloned: Result /= implementation.text
			no_carriage_returns: not Result.has ('%R')

	text_alignment: INTEGER_32
			-- Current alignment.
			-- See class EV_TEXT_ALIGNABLE_CONSTANTS for
			-- possible values.
			-- (from EV_TEXT_ALIGNABLE)
		require -- from EV_TEXT_ALIGNABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_TEXT_ALIGNABLE
			bridge_ok: Result = implementation.text_alignment

	user_can_resize: BOOLEAN
			-- Can a user resize `Current'?
			-- (from EV_HEADER_ITEM)
		require -- from EV_HEADER_ITEM
			not_destroyed: not is_destroyed
		ensure -- from EV_HEADER_ITEM
			bridge_ok: Result = implementation.user_can_resize

	width: INTEGER_32
			-- `Result' is width of `Current' used
			-- while parented.
			-- (from EV_HEADER_ITEM)
		require -- from EV_HEADER_ITEM
			not_destroyed: not is_destroyed
		ensure -- from EV_HEADER_ITEM
			result_non_negative: 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

	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

	is_center_aligned: BOOLEAN
			-- Is `Current' center aligned?
			-- (from EV_TEXT_ALIGNABLE)
		require -- from EV_TEXT_ALIGNABLE
			not_destroyed: not is_destroyed

	is_left_aligned: BOOLEAN
			-- Is `Current' left aligned?
			-- (from EV_TEXT_ALIGNABLE)
		require -- from EV_TEXT_ALIGNABLE
			not_destroyed: not is_destroyed

	is_right_aligned: BOOLEAN
			-- Is `Current' right aligned?
			-- (from EV_TEXT_ALIGNABLE)
		require -- from EV_TEXT_ALIGNABLE
			not_destroyed: not is_destroyed

	mode_is_drag_and_drop: BOOLEAN
			-- Is the user interface mode drag and drop?
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure then -- from EV_PICK_AND_DROPABLE
			bridge_ok: Result = implementation.mode_is_drag_and_drop

	mode_is_pick_and_drop: BOOLEAN
			-- Is the user interface mode pick and drop?
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure then -- from EV_PICK_AND_DROPABLE
			bridge_ok: Result = implementation.mode_is_pick_and_drop

	mode_is_target_menu: BOOLEAN
			-- Is the user interface mode a pop-up menu of targets?
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure then -- from EV_PICK_AND_DROPABLE
			bridge_ok: Result = implementation.mode_is_target_menu

	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))
	
feature -- Status setting

	align_text_center
			-- Display text centered.
			-- (from EV_TEXT_ALIGNABLE)
		require -- from EV_TEXT_ALIGNABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_TEXT_ALIGNABLE
			alignment_set: is_center_aligned

	align_text_left
			-- Display text left aligned.
			-- (from EV_TEXT_ALIGNABLE)
		require -- from EV_TEXT_ALIGNABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_TEXT_ALIGNABLE
			alignment_set: is_left_aligned

	align_text_right
			-- Display text right aligned.
			-- (from EV_TEXT_ALIGNABLE)
		require -- from EV_TEXT_ALIGNABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_TEXT_ALIGNABLE
			alignment_set: is_right_aligned

	disable_pebble_positioning
			-- Assign `False' to pebble_positioning_enabled.
			-- The pick and drop will start at the pointer position.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_PICK_AND_DROPABLE
			pebble_positioning_updated: not pebble_positioning_enabled

	disable_user_resize
			-- Prevent `Current' from being resized by users.
			-- (from EV_HEADER_ITEM)
		require -- from EV_HEADER_ITEM
			not_destroyed: not is_destroyed
		ensure -- from EV_HEADER_ITEM
			not_user_can_resize: not user_can_resize

	enable_pebble_positioning
			-- Assign `True' to pebble_positioning_enabled.
			-- Use pebble_x_position and pebble_y_position as the initial coordinates
			-- for the pick and drop in pixels relative to `Current'.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_PICK_AND_DROPABLE
			pebble_positioning_updated: pebble_positioning_enabled

	enable_user_resize
			-- Permit `Current' from being resized by users.
			-- (from EV_HEADER_ITEM)
		require -- from EV_HEADER_ITEM
			not_destroyed: not is_destroyed
		ensure -- from EV_HEADER_ITEM
			user_can_resize: user_can_resize

	remove_pebble
			-- Make pebble `Void' and pebble_function `Void,
			-- Removing transport.
			-- (from EV_PICK_AND_DROPABLE)
		ensure -- from EV_ABSTRACT_PICK_AND_DROPABLE
			pebble_removed: pebble = Void and pebble_function = Void

	resize_to_content
			-- Resize `Current' to fully display both pixmap and text.
			-- As size of text is dependent on `font' of parent, `Current'
			-- must be parented. Note that the width is still restricted to
			-- minimum_width and maximum_width.
			-- (from EV_HEADER_ITEM)
		require -- from EV_HEADER_ITEM
			not_destroyed: not is_destroyed
			parent_not_void: parent /= Void

	set_accept_cursor (a_cursor: like accept_cursor)
			-- Set `a_cursor' to be displayed when the screen pointer is over a
			-- target that accepts pebble during pick and drop.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_ABSTRACT_PICK_AND_DROPABLE
			a_cursor_not_void: a_cursor /= Void
		ensure -- from EV_ABSTRACT_PICK_AND_DROPABLE
			accept_cursor_assigned: accept_cursor.is_equal (a_cursor)

	set_deny_cursor (a_cursor: like deny_cursor)
			-- Set `a_cursor' to be displayed when the screen pointer is not
			-- over a valid target.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_ABSTRACT_PICK_AND_DROPABLE
			a_cursor_not_void: a_cursor /= Void
		ensure -- from EV_ABSTRACT_PICK_AND_DROPABLE
			deny_cursor_assigned: deny_cursor.is_equal (a_cursor)

	set_drag_and_drop_mode
			-- Set user interface mode to drag and drop.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_PICK_AND_DROPABLE
			drag_and_drop_set: mode_is_drag_and_drop

	set_maximum_width (a_maximum_width: INTEGER_32)
			-- Assign `a_maximum_width' in pixels to maximum_width.
			-- If width is greater than `a_maximum_width', resize.
			-- (from EV_HEADER_ITEM)
		require -- from EV_HEADER_ITEM
			not_destroyed: not is_destroyed
			a_maximum_width_positive: a_maximum_width >= 0
			maximum_width_greater_than_or_equal_to_minimum_width: maximum_width >= minimum_width
		ensure -- from EV_HEADER_ITEM
			maximum_width_assigned: maximum_width = a_maximum_width

	set_minimum_width (a_minimum_width: INTEGER_32)
			-- Assign `a_minimum_width' in pixels to minimum_width.
			-- If width is less than `a_minimum_width', resize.
			-- (from EV_HEADER_ITEM)
		require -- from EV_HEADER_ITEM
			not_destroyed: not is_destroyed
			a_minimum_width_positive: a_minimum_width >= 0
			minimum_width_less_than_or_equal_to_maximum_width: minimum_width <= maximum_width
		ensure -- from EV_HEADER_ITEM
			minimum_width_assigned: minimum_width = a_minimum_width

	set_pebble (a_pebble: like pebble)
			-- Assign `a_pebble' to pebble.
			-- Overrides set_pebble_function.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_ABSTRACT_PICK_AND_DROPABLE
			a_pebble_not_void: a_pebble /= Void
		ensure -- from EV_ABSTRACT_PICK_AND_DROPABLE
			pebble_assigned: pebble = a_pebble

	set_pebble_function (a_function: FUNCTION [ANY, TUPLE, ANY])
			-- Set `a_function' to compute pebble.
			-- It will be called once each time a pick occurs, the result
			-- will be assigned to pebble for the duration of transport.
			-- When a pick occurs, the pick position in widget coordinates,
			-- <<x, y>> in pixels, is passed.
			-- To handle this data use `a_function' of type
			-- FUNCTION [ANY, TUPLE [INTEGER, INTEGER], ANY] and return the
			-- pebble as a function of x and y.
			-- Overrides set_pebble.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_ABSTRACT_PICK_AND_DROPABLE
			a_function_not_void: a_function /= Void
			a_function_takes_two_integer_open_operands: a_function.valid_operands ([1, 1])
		ensure -- from EV_ABSTRACT_PICK_AND_DROPABLE
			pebble_function_assigned: pebble_function = a_function

	set_pebble_position (a_x, a_y: INTEGER_32)
			-- Set the initial position for pick and drop
			-- Coordinates are in pixels and are relative to position of `Current'.
			-- Pebble_positioning_enabled must be `True' for the position to be used,
			-- use enable_pebble_positioning.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_PICK_AND_DROPABLE
			pebble_position_assigned: pebble_x_position = a_x and pebble_y_position = a_y

	set_pick_and_drop_mode
			-- Set user interface mode to pick and drop.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_PICK_AND_DROPABLE
			pick_and_drop_set: mode_is_pick_and_drop

	set_target_menu_mode
			-- Set user interface mode to pop-up menu of targets.
			-- (from EV_PICK_AND_DROPABLE)
		require -- from EV_PICK_AND_DROPABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_PICK_AND_DROPABLE
			target_menu_mode_set: mode_is_target_menu

	set_target_name (a_name: STRING_GENERAL)
			-- Assign `a_name' to target_name.
			-- (from EV_ABSTRACT_PICK_AND_DROPABLE)
		require -- from EV_ABSTRACT_PICK_AND_DROPABLE
			a_name_not_void: a_name /= Void
		ensure -- from EV_ABSTRACT_PICK_AND_DROPABLE
			target_name_assigned: a_name /= target_name and a_name.is_equal (target_name)

	set_width (a_width: INTEGER_32)
			-- Assign `a_width' to width.
			-- (from EV_HEADER_ITEM)
		require -- from EV_HEADER_ITEM
			not_destroyed: not is_destroyed
			width_non_negative: a_width >= 0
			width_greater_than_or_equal_to_minimum_width: a_width >= minimum_width
			width_less_than_or_equal_to_maximum_width: a_width <= maximum_width
		ensure -- from EV_HEADER_ITEM
			width_set: width = a_width
	
feature -- Element change

	remove_pixmap
			-- Remove image displayed on `Current'.
			-- (from EV_PIXMAPABLE)
		require -- from EV_PIXMAPABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_PIXMAPABLE
			pixmap_removed: pixmap = Void

	remove_text
			-- Make text `is_empty'.
			-- (from EV_TEXTABLE)
		require -- from EV_TEXTABLE
			not_destroyed: not is_destroyed
		ensure -- from EV_TEXTABLE
			text_empty: text.is_empty

	set_data (some_data: like data)
			-- Assign `some_data' to data.
			-- (from EV_ANY)
		require -- from EV_ANY
			not_destroyed: not is_destroyed
		ensure -- from EV_ANY
			data_assigned: data = some_data

	set_pixmap (a_pixmap: EV_PIXMAP)
			-- Display image of `a_pixmap' on `Current'.
			-- Image of pixmap will be a copy of `a_pixmap'.
			-- Image may be scaled in some descendents, i.e EV_TREE_ITEM
			-- See EV_TREE.set_pixmaps_size.
			-- (from EV_PIXMAPABLE)
		require -- from EV_PIXMAPABLE
			not_destroyed: not is_destroyed
			pixmap_not_void: a_pixmap /= Void

	set_text (a_text: STRING_GENERAL)
			-- Assign `a_text' to text.
			-- (from EV_TEXTABLE)
		require -- from EV_TEXTABLE
			not_destroyed: not is_destroyed
			a_text_not_void: a_text /= Void
			no_carriage_returns: not a_text.has_code (('%R').natural_32_code)
		ensure -- from EV_TEXTABLE
			text_cloned: text.is_equal (a_text) and then text /= a_text
	
feature -- Duplication

	copy (other: like Current)
			-- Update current object using fields of object attached
			-- to `other', so as to yield equal objects.
			-- (from EV_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 -- Command

	destroy
			-- Destroy underlying native toolkit object.
			-- Render `Current' unusable.
			-- (from EV_ANY)
		ensure -- from EV_ANY
			is_destroyed: is_destroyed
	
feature -- Event handling

	conforming_pick_actions: EV_NOTIFY_ACTION_SEQUENCE
			-- Actions to be performed when a pebble that fits here is picked.
			-- (from EV_PICK_AND_DROPABLE_ACTION_SEQUENCES)
		require -- from  EV_ABSTRACT_PICK_AND_DROPABLE
			True
		ensure -- from EV_PICK_AND_DROPABLE_ACTION_SEQUENCES
			not_void: Result /= Void

	drop_actions: EV_PND_ACTION_SEQUENCE
			-- Actions to be performed when a pebble is dropped here.
			-- (from EV_PICK_AND_DROPABLE_ACTION_SEQUENCES)
		require -- from  EV_ABSTRACT_PICK_AND_DROPABLE
			True
		ensure -- from EV_PICK_AND_DROPABLE_ACTION_SEQUENCES
			not_void: Result /= Void

	pick_actions: EV_PND_START_ACTION_SEQUENCE
			-- Actions to be performed when pebble is picked up.
			-- (from EV_PICK_AND_DROPABLE_ACTION_SEQUENCES)
		require -- from  EV_ABSTRACT_PICK_AND_DROPABLE
			True
		ensure -- from EV_PICK_AND_DROPABLE_ACTION_SEQUENCES
			not_void: Result /= Void

	pick_ended_actions: EV_PND_FINISHED_ACTION_SEQUENCE
			-- Actions to be performed when a transport from `Current' ends.
			-- If transport completed successfully, then event data
			-- is target. If cancelled, then event data is Void.
			-- (from EV_PICK_AND_DROPABLE_ACTION_SEQUENCES)
		ensure -- from EV_PICK_AND_DROPABLE_ACTION_SEQUENCES
			not_void: Result /= Void

	pointer_button_press_actions: EV_POINTER_BUTTON_ACTION_SEQUENCE
			-- Actions to be performed when screen pointer button is pressed.
			-- (from EV_ITEM_ACTION_SEQUENCES)
		ensure -- from EV_ITEM_ACTION_SEQUENCES
			not_void: Result /= Void

	pointer_double_press_actions: EV_POINTER_BUTTON_ACTION_SEQUENCE
			-- Actions to be performed when screen pointer is double clicked.
			-- (from EV_ITEM_ACTION_SEQUENCES)
		ensure -- from EV_ITEM_ACTION_SEQUENCES
			not_void: Result /= Void

	pointer_motion_actions: EV_POINTER_MOTION_ACTION_SEQUENCE
			-- Actions to be performed when screen pointer moves.
			-- (from EV_ITEM_ACTION_SEQUENCES)
		require -- from  EV_ABSTRACT_PICK_AND_DROPABLE
			True
		ensure -- from EV_ITEM_ACTION_SEQUENCES
			not_void: Result /= 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)
	
feature -- Status Report

	is_destroyed: BOOLEAN
			-- Is `Current' no longer usable?
			-- (from EV_ANY)
		ensure -- from EV_ANY
			bridge_ok: Result = implementation.is_destroyed
	
invariant
	column_not_void: column /= Void
	parented_whilst_in_grid: column.is_displayed implies column.parent.header = parent

		-- from EV_HEADER_ITEM
	width_greater_than_or_equal_to_minimum_width: width >= minimum_width
	width_less_than_or_equal_to_maximum_width: width <= maximum_width
	minimum_width_less_than_or_equal_to_maximum_width: minimum_width <= maximum_width

		-- from EV_PICK_AND_DROPABLE
	user_interface_modes_mutually_exclusive: mode_is_pick_and_drop.to_integer + mode_is_drag_and_drop.to_integer + mode_is_target_menu.to_integer = 1

		-- from EV_ANY
	is_initialized: is_initialized
	is_coupled: implementation /= Void and then implementation.interface = Current
	default_create_called: default_create_called

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

		-- from EV_TEXT_ALIGNABLE
	valid_alignment: (create {EV_TEXT_ALIGNMENT_CONSTANTS}).valid_alignment (text_alignment)

		-- from EV_TEXTABLE
	text_not_void: is_usable implies text /= Void

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_HEADER_ITEM