source: trunk/doc/src/snippets/qlistview-using/model.cpp@ 846

Last change on this file since 846 was 846, checked in by Dmitry A. Kuminov, 14 years ago

trunk: Merged in qt 4.7.2 sources from branches/vendor/nokia/qt.
File size: 5.4 KB
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1/****************************************************************************
2**
3** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
4** All rights reserved.
5** Contact: Nokia Corporation ([email protected])
6**
7** This file is part of the documentation of the Qt Toolkit.
8**
9** $QT_BEGIN_LICENSE:BSD$
10** You may use this file under the terms of the BSD license as follows:
11**
12** "Redistribution and use in source and binary forms, with or without
13** modification, are permitted provided that the following conditions are
14** met:
15** * Redistributions of source code must retain the above copyright
16** notice, this list of conditions and the following disclaimer.
17** * Redistributions in binary form must reproduce the above copyright
18** notice, this list of conditions and the following disclaimer in
19** the documentation and/or other materials provided with the
20** distribution.
21** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
22** the names of its contributors may be used to endorse or promote
23** products derived from this software without specific prior written
24** permission.
25**
26** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
27** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
28** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
29** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
30** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
31** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
32** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
36** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
37** $QT_END_LICENSE$
38**
39****************************************************************************/
40
41/****************************************************************************
42**
43** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
44** All rights reserved.
45** Contact: Nokia Corporation ([email protected])
46**
47** This file is part of an example program for Qt.
48** EDITIONS: NOLIMITS
49**
50****************************************************************************/
51
52/*
53 model.cpp
54
55 A simple model that uses a QStringList as its data source.
56*/
57
58#include "model.h"
59
60/*!
61 Returns the number of items in the string list as the number of rows
62 in the model.
63*/
64
65int StringListModel::rowCount(const QModelIndex &parent) const
66{
67 return stringList.count();
68}
69
70/*!
71 Returns an appropriate value for the requested data.
72 If the view requests an invalid index, an invalid variant is returned.
73 Any valid index that corresponds to a string in the list causes that
74 string to be returned.
75*/
76
77QVariant StringListModel::data(const QModelIndex &index, int role) const
78{
79 if (!index.isValid())
80 return QVariant();
81
82 if (index.row() >= stringList.size())
83 return QVariant();
84
85 if (role == Qt::DisplayRole)
86 return stringList.at(index.row());
87 else
88 return QVariant();
89}
90
91/*!
92 Returns the appropriate header string depending on the orientation of
93 the header and the section. If anything other than the display role is
94 requested, we return an invalid variant.
95*/
96
97QVariant StringListModel::headerData(int section, Qt::Orientation orientation,
98 int role) const
99{
100 if (role != Qt::DisplayRole)
101 return QVariant();
102
103 if (orientation == Qt::Horizontal)
104 return QString("Column %1").arg(section);
105 else
106 return QString("Row %1").arg(section);
107}
108
109/*!
110 Returns an appropriate value for the item's flags. Valid items are
111 enabled, selectable, and editable.
112*/
113
114Qt::ItemFlags StringListModel::flags(const QModelIndex &index) const
115{
116 if (!index.isValid())
117 return Qt::ItemIsEnabled;
118
119 return QAbstractItemModel::flags(index) | Qt::ItemIsEditable;
120}
121
122/*!
123 Changes an item in the string list, but only if the following conditions
124 are met:
125
126 * The index supplied is valid.
127 * The index corresponds to an item to be shown in a view.
128 * The role associated with editing text is specified.
129
130 The dataChanged() signal is emitted if the item is changed.
131*/
132
133bool StringListModel::setData(const QModelIndex &index,
134 const QVariant &value, int role)
135{
136 if (index.isValid() && role == Qt::EditRole) {
137
138 stringList.replace(index.row(), value.toString());
139 emit dataChanged(index, index);
140 return true;
141 }
142 return false;
143}
144
145/*!
146 Inserts a number of rows into the model at the specified position.
147*/