indexing
	description: "The TV_DISPINFO structure retrieves and sets information about a scroll bar item."
	status: "See notice at end of class."
	date: "$Date$"
	revision: "$Revision$"

class interface
	WEL_SCROLL_BAR_INFO

create 

	make
			-- Create SCROLLINFO struct

feature -- Access

	item: POINTER
			-- Generic Windows handle or structure pointer.
			-- Can be a HWND, HICON, RECT *, WNDCLASS *, etc...
			-- (from WEL_ANY)

	mask: INTEGER
			-- fmask associated with Current
		require
			exists: exists
		ensure
			valid_mask: valid_sif_constant (Result)

	maximum: INTEGER
			-- nMax associated with Current
		require
			exists: exists

	minimum: INTEGER
			-- nMin associated with Current
		require
			exists: exists

	page: INTEGER
			-- nMax associated with Current
		require
			exists: exists

	position: INTEGER
			-- nPos associated with Current
		require
			exists: exists

	track_position: INTEGER
			-- nTrackPos associated with Current
		require
			exists: exists
	
feature -- Measurement

	structure_size: INTEGER
			-- Size to allocate (in bytes)
		ensure -- from WEL_STRUCTURE
			positive_result: Result > 0
	
feature -- Status report

	exists: BOOLEAN
			-- Does the item exist?
			-- (from WEL_ANY)
		ensure -- from WEL_ANY
			Result = (item /= default_pointer)

	shared: BOOLEAN
			-- Is item shared by another object?
			-- If False (by default), item will
			-- be destroyed by destroy_item.
			-- If True, item will not be destroyed.
			-- (from WEL_ANY)
	
feature -- Status setting

	set_shared
			-- Set shared to True.
			-- (from WEL_ANY)
		ensure -- from WEL_ANY
			shared: shared

	set_unshared
			-- Set shared to False.
			-- (from WEL_ANY)
		ensure -- from WEL_ANY
			unshared: not shared
	
feature -- Element change

	set_item (an_item: POINTER)
			-- Set item with an_item
			-- (from WEL_ANY)
		ensure -- from WEL_ANY
			item_set: item = an_item
	
feature -- Removal

	dispose
			-- Destroy the inner structure of Current.
			--
			-- This function should be called by the GC when the
			-- object is collected or by the user if Current is
			-- no more usefull.
			-- (from WEL_ANY)
	
feature -- Conversion

	to_integer: INTEGER
			-- Converts item to an integer.
			-- (from WEL_ANY)
		ensure -- from WEL_ANY
			Result = cwel_pointer_to_integer (item)
	
feature -- Basic operations

	initialize
			-- Fill Current with zeros.
			-- (from WEL_STRUCTURE)
		require -- from WEL_STRUCTURE
			exists: exists

	initialize_with_character (a_character: CHARACTER)
			-- Fill current with a_character.
			-- (from WEL_STRUCTURE)
		require -- from WEL_STRUCTURE
			exists: exists

	memory_copy (source_pointer: POINTER; length: INTEGER)
			-- Copy length bytes from source_pointer to item.
			-- (from WEL_STRUCTURE)
		require -- from WEL_STRUCTURE
			length_small_enough: length <= structure_size
			length_large_enough: length > 0
			exists: exists
	
feature  -- ScrollInfo

	valid_sif_constant (i: INTEGER): BOOLEAN
			-- Is i a valid Sif constant?
			-- (from WEL_SCROLL_BAR_CONSTANTS)
	
feature -- Setting

	set_mask (i: INTEGER)
			-- Assign i to fmask field of Current.
		require
			exists: exists
			valid_mask: valid_sif_constant (i)

	set_maximum (i: INTEGER)
			-- nMax associated with Current
		require
			exists: exists

	set_minimum (i: INTEGER)
			-- nMin associated with Current
		require
			exists: exists

	set_page (i: INTEGER)
			-- npage associated with Current
		require
			exists: exists

	set_position (i: INTEGER)
			-- nPos associated with Current
		require
			exists: exists

	set_track_position (i: INTEGER)
			-- nTrackPos associated with Current
		require
			exists: exists
	
invariant

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

end -- class WEL_SCROLL_BAR_INFO