/src/wrappers/gtk/library/change_value_callback.e

 1indexing
 2	description: "Generic callback for the change-value signal"
 3	copyright: "[
 4					Copyright (C) 2006 Paolo redaelli, eiffel-libraries team,  GTK+ team and others
 5					
 6					This library is free software; you can redistribute it and/or
 7					modify it under the terms of the GNU Lesser General Public License
 8					as published by the Free Software Foundation; either version 2.1 of
 9					the License, or (at your option) any later version.
10					
11					This library is distributed in the hope that it will be useful, but
12					WITHOUT ANY WARRANTY; without even the implied warranty of
13					MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14					Lesser General Public License for more details.
15
16					You should have received a copy of the GNU Lesser General Public
17					License along with this library; if not, write to the Free Software
18					Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19					02110-1301 USA
20				]"
21	license: "LGPL v2 or later"
22	date: "$Date:$"
23	revision "$Revision:$"
24
25class CHANGE_VALUE_CALLBACK
26
27inherit CALLBACK redefine object end
28
29insert G_OBJECT_FACTORY [GTK_RANGE]
30
31creation make
32
33feature
34	object: GTK_RANGE
35
36feature
37	callback (value: REAL; scroll: INTEGER; instance: POINTER): INTEGER is
38		require
39			instance_not_null: instance.is_not_null
40		do
41			debug
42				print ("Callback: instance=") print (instance.to_string) print ("%N")
43				print ("is_object: "+g_is_object (instance).out+"%N")
44				print ("type: "+g_object_type (instance).out+"%N")
45			end
46			object := wrapper(instance)
47			Result := function.item ([value, scroll, object]).to_integer
48		end
49
50	callback_pointer: POINTER is
51		do
52			Result := get_callback_pointer ($callback)
53		ensure
54			Result.is_not_null
55		end
56
57	connect (an_object: GTK_RANGE; a_function: FUNCTION[ANY, TUPLE [REAL, INTEGER, GTK_RANGE], BOOLEAN]) is
58		do
59			debug
60				print ("CHANGE_VALUE_CALLBACK.connect (an_object=") print (an_object.to_pointer.to_string)
61				print (" an_object.handle=") print (an_object.handle.to_string)
62				print (") Current=") print (to_pointer.to_string)
63				print (" Current.handle=") print (handle.to_string)
64				print ("%N")
65			end
66			
67			handler_id := g_signal_connect_closure (an_object.handle,
68																 signal_name.to_external,
69																 handle,
70																 0 -- i.e. call it before default handler
71																)
72			function:=a_function
73		end
74
75	signal_name: STRING is "change-value"
76
77	function: FUNCTION[ANY, TUPLE [REAL, INTEGER, GTK_RANGE], BOOLEAN]
78end