1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
|
/*
* Copyright (C) 2014 David Robillard <d@drobilla.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef __ardour_gtk_cursor_context_h__
#define __ardour_gtk_cursor_context_h__
#include <boost/shared_ptr.hpp>
#include <gdkmm/cursor.h>
class Editor;
/**
A scoped handle for changing the editor mouse cursor.
This is a safe way to change the cursor that ensures it is only modified in
a strict stack-like fashion. Whenever this handle goes out of scope, the
cursor is restored to the previous one.
This is not quite entirely fool-proof, there is one case to be careful of:
if a cursor context handle exists, to change it, you must first reset that
handle (destroying the context) then set it. Assigning a new context to a
non-NULL handle will create the new context (pushing a cursor), then destroy
the old one, which would attempt to pop a non-top context which is an
error. To account for this, when replacing a possibly existing context, use
set() which will automatically do the right thing.
*/
class CursorContext
{
public:
/** A smart handle for a cursor change context. */
typedef boost::shared_ptr<CursorContext> Handle;
~CursorContext();
/** Change the editor cursor and return a cursor context handle.
*
* When the returned handle goes out of scope, the cursor will be reset to
* the previous value.
*/
static Handle create(Editor& editor, Gdk::Cursor* cursor);
/** Change the editor cursor of an existing cursor context. */
void change(Gdk::Cursor* cursor);
/** Set a context handle to a new context.
*
* If the handle points to an existing context, it will first be reset
* before the new context is created.
*/
static void set(Handle* handle, Editor& editor, Gdk::Cursor* cursor);
private:
Editor& _editor;
size_t _index;
CursorContext(Editor& editor, Gdk::Cursor* cursor);
};
#endif /* __ardour_gtk_cursor_context_h__ */
|
