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
85
86
87
88
89
90
91
92
93
94
|
/****************************************************************************
**
** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia. For licensing terms and
** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Free Documentation License Usage
** Alternatively, this file may be used under the terms of the GNU Free
** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file. Please review the following information to ensure
** the GNU Free Documentation License version 1.3 requirements
** will be met: http://www.gnu.org/copyleft/fdl.html.
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\example uitools/multipleinheritance
\title Multiple Inheritance Example
\brief The Multiple Inheritance Example shows how to use a form created with \QD
in an application by subclassing both QWidget and the user interface
class, which is \c{Ui::CalculatorForm}.
\image multipleinheritance-example.png
To subclass the \c calculatorform.ui file and ensure that \c qmake
processes it with the \c uic, we have to include \c calculatorform.ui
in the \c .pro file, as shown below:
\snippet examples/uitools/multipleinheritance/multipleinheritance.pro 0
When the project is compiled, the \c uic will generate a corresponding
\c ui_calculatorform.h.
\section1 CalculatorForm Definition
In the \c CalculatorForm definition, we include the \c ui_calculatorform.h
that was generated earlier.
\snippet examples/uitools/multipleinheritance/calculatorform.h 0
As mentioned earlier, the class is a subclass of both QWidget and
\c{Ui::CalculatorForm}.
\snippet examples/uitools/multipleinheritance/calculatorform.h 1
Two slots are defined according to the \l{Automatic Connections}
{automatic connection} naming convention required by \c uic. This is
to ensure that \l{QMetaObject}'s auto-connection facilities connect
all the signals and slots involved automatically.
\section1 CalculatorForm Implementation
In the constructor, we call \c setupUi() to load the user interface file.
Note that we do not need the \c{ui} prefix as \c CalculatorForm is a
subclass of the user interface class.
\snippet examples/uitools/multipleinheritance/calculatorform.cpp 0
We include two slots, \c{on_inputSpinBox1_valueChanged()} and
\c{on_inputSpinBox2_valueChanged()}. These slots respond to the
\l{QSpinBox::valueChanged()}{valueChanged()} signal that both spin boxes
emit. Whenever there is a change in one spin box's value, we take that
value and add it to whatever value the other spin box has.
\snippet examples/uitools/multipleinheritance/calculatorform.cpp 1
\codeline
\snippet examples/uitools/multipleinheritance/calculatorform.cpp 2
\section1 \c main() Function
The \c main() function instantiates QApplication and \c CalculatorForm.
The \c calculator object is displayed by invoking the \l{QWidget::show()}
{show()} function.
\snippet examples/uitools/multipleinheritance/main.cpp 0
There are various approaches to include forms into applications. The
Multiple Inheritance approach is just one of them. See
\l{Using a Designer UI File in Your Application} for more information on
the other approaches available.
*/
|