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
75
76
77
78
79
80
81
82
83
84
|
/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
** the names of its contributors may be used to endorse or promote
** products derived from this software without specific prior written
** permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QAbstractButton>
#include "signalsandslots.h"
//! [0]
void Counter::setValue(int value)
{
if (value != m_value) {
m_value = value;
emit valueChanged(value);
}
}
//! [0]
int main()
{
//! [1]
Counter a, b;
//! [1] //! [2]
QObject::connect(&a, &Counter::valueChanged,
&b, &Counter::setValue);
//! [2]
//! [3]
a.setValue(12); // a.value() == 12, b.value() == 12
//! [3] //! [4]
b.setValue(48); // a.value() == 12, b.value() == 48
//! [4]
QWidget *widget = reinterpret_cast<QWidget *>(new QObject(0));
//! [5]
if (widget->inherits("QAbstractButton")) {
QAbstractButton *button = static_cast<QAbstractButton *>(widget);
button->toggle();
//! [5] //! [6]
}
//! [6]
//! [7]
if (QAbstractButton *button = qobject_cast<QAbstractButton *>(widget))
button->toggle();
//! [7]
}
|
