/tutorial/vision/multi_tasking/kitchen_clock.e

  1class KITCHEN_CLOCK
  2--
  3-- An old style kitchen clock.
  4--
  5	
  6inherit
  7	GRAPHIC
  8	LAYOUT
  9		redefine set_container
 10		end
 11
 12creation {ANY}
 13	default_create
 14
 15feature {}
 16	pen1, pen2: DRAW_KIT
 17
 18feature {ANY}
 19	w: WINDOW
 20
 21	set_container (c: CONTAINER) is
 22		local
 23			update: SIMPLE_PERIODIC_JOB
 24		do
 25			check
 26				c /= Void
 27			end
 28			w ::= c
 29			container := c
 30			create pen1
 31			create pen2
 32			pen2.set_line_width(5)
 33			pen2.set_color(magenta_color)
 34			w.set_background_color(white_color)
 35			w.set_requisition(10, 10, 30, 30)
 36			create update.set_work(agent redraw, Void, 1, 1.0)
 37			vision.loop_stack.add_job(update)
 38		end
 39
 40	redo_layout (x, y: INTEGER) is
 41		local
 42			i: INTEGER; widget: WIDGET
 43		do
 44			from
 45				i := container.child.upper
 46			until
 47				i < container.child.lower
 48			loop
 49				widget := container.child.item(i)
 50				if not widget.valid_width(widget.width) or else not widget.valid_height(widget.height) then
 51					widget.set_geometry(0, 20, widget.std_width, widget.std_height)
 52				end
 53				i := i - 1
 54			end
 55		end
 56
 57	update_requisition is
 58		do
 59			w.set_requisition(w.min_width, w.min_height, w.std_width, w.std_height)
 60		end
 61
 62feature {CONTAINER}
 63	expose_paint is
 64		do
 65			draw
 66		end
 67
 68feature {}
 69	draw is
 70		local
 71			time: TIME; angle: REAL_64; english_string: STRING
 72		do
 73			pen1.set_drawable(w)
 74			pen2.set_drawable(w)
 75			english_string := once " ... local private persistant buffer ... "
 76			time.update
 77			angle := (time.second - 15) / 60 * 2 * 3.1415926
 78			pen2.line(w.width // 2,
 79						 w.height // 2,
 80						 w.width // 2 + (w.width / 2 * angle.cos).floor.force_to_integer_32,
 81						 w.height // 2 + (w.height / 2 * angle.sin).floor.force_to_integer_32)
 82			angle := ((time.hour - 3) / 12 + time.minute / (60 * 12)) * 2 * 3.1415926
 83			pen1.line(w.width // 2,
 84						 w.height // 2,
 85						 w.width // 2 + (w.width / 4 * angle.cos).floor.force_to_integer_32,
 86						 w.height // 2 + (w.height / 4 * angle.sin).floor.force_to_integer_32)
 87			angle := (time.minute - 15) / 60 * 2 * 3.1415926
 88			pen1.line(w.width // 2,
 89						 w.height // 2,
 90						 w.width // 2 + (w.width / 2 * angle.cos).floor.force_to_integer_32,
 91						 w.height // 2 + (w.height / 2 * angle.sin).floor.force_to_integer_32)
 92			english_string.clear_count
 93			time_formatter.set_time(time)
 94			time_formatter.append_in(english_string)
 95			unicode_string.clear_count
 96			if unicode_string.utf8_decode_from(english_string) then
 97				pen2.put_string(unicode_string, 0, 0)
 98			end
 99		end
100
101	time_formatter: TIME_FORMATTER is
102		once
103			create {TIME_IN_ENGLISH}Result
104		end
105
106	redraw: BOOLEAN is
107		do
108			w.clear
109			Result := True
110		end
111
112	unicode_string: UNICODE_STRING is
113		once
114			create Result.make(0)
115		end
116
117end -- class KITCHEN_CLOCK