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
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
|
/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples 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 <QtGui>
#include "mainwindow.h"
#include "scribblearea.h"
//! [0]
MainWindow::MainWindow()
{
scribbleArea = new ScribbleArea;
setCentralWidget(scribbleArea);
createActions();
createMenus();
setWindowTitle(tr("Scribble"));
resize(500, 500);
}
//! [0]
//! [1]
void MainWindow::closeEvent(QCloseEvent *event)
//! [1] //! [2]
{
if (maybeSave()) {
event->accept();
} else {
event->ignore();
}
}
//! [2]
//! [3]
void MainWindow::open()
//! [3] //! [4]
{
if (maybeSave()) {
QString fileName = QFileDialog::getOpenFileName(this,
tr("Open File"), QDir::currentPath());
if (!fileName.isEmpty())
scribbleArea->openImage(fileName);
}
}
//! [4]
//! [5]
void MainWindow::save()
//! [5] //! [6]
{
QAction *action = qobject_cast<QAction *>(sender());
QByteArray fileFormat = action->data().toByteArray();
saveFile(fileFormat);
}
//! [6]
//! [7]
void MainWindow::penColor()
//! [7] //! [8]
{
QColor newColor = QColorDialog::getColor(scribbleArea->penColor());
if (newColor.isValid())
scribbleArea->setPenColor(newColor);
}
//! [8]
//! [9]
void MainWindow::penWidth()
//! [9] //! [10]
{
bool ok;
int newWidth = QInputDialog::getInteger(this, tr("Scribble"),
tr("Select pen width:"),
scribbleArea->penWidth(),
1, 50, 1, &ok);
if (ok)
scribbleArea->setPenWidth(newWidth);
}
//! [10]
//! [11]
void MainWindow::about()
//! [11] //! [12]
{
QMessageBox::about(this, tr("About Scribble"),
tr("<p>The <b>Scribble</b> example shows how to use QMainWindow as the "
"base widget for an application, and how to reimplement some of "
"QWidget's event handlers to receive the events generated for "
"the application's widgets:</p><p> We reimplement the mouse event "
"handlers to facilitate drawing, the paint event handler to "
"update the application and the resize event handler to optimize "
"the application's appearance. In addition we reimplement the "
"close event handler to intercept the close events before "
"terminating the application.</p><p> The example also demonstrates "
"how to use QPainter to draw an image in real time, as well as "
"to repaint widgets.</p>"));
}
//! [12]
//! [13]
void MainWindow::createActions()
//! [13] //! [14]
{
openAct = new QAction(tr("&Open..."), this);
openAct->setShortcuts(QKeySequence::Open);
connect(openAct, SIGNAL(triggered()), this, SLOT(open()));
foreach (QByteArray format, QImageWriter::supportedImageFormats()) {
QString text = tr("%1...").arg(QString(format).toUpper());
QAction *action = new QAction(text, this);
action->setData(format);
connect(action, SIGNAL(triggered()), this, SLOT(save()));
saveAsActs.append(action);
}
printAct = new QAction(tr("&Print..."), this);
connect(printAct, SIGNAL(triggered()), scribbleArea, SLOT(print()));
exitAct = new QAction(tr("E&xit"), this);
exitAct->setShortcuts(QKeySequence::Quit);
connect(exitAct, SIGNAL(triggered()), this, SLOT(close()));
penColorAct = new QAction(tr("&Pen Color..."), this);
connect(penColorAct, SIGNAL(triggered()), this, SLOT(penColor()));
penWidthAct = new QAction(tr("Pen &Width..."), this);
connect(penWidthAct, SIGNAL(triggered()), this, SLOT(penWidth()));
clearScreenAct = new QAction(tr("&Clear Screen"), this);
clearScreenAct->setShortcut(tr("Ctrl+L"));
connect(clearScreenAct, SIGNAL(triggered()),
scribbleArea, SLOT(clearImage()));
aboutAct = new QAction(tr("&About"), this);
connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));
aboutQtAct = new QAction(tr("About &Qt"), this);
connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));
}
//! [14]
//! [15]
void MainWindow::createMenus()
//! [15] //! [16]
{
saveAsMenu = new QMenu(tr("&Save As"), this);
foreach (QAction *action, saveAsActs)
saveAsMenu->addAction(action);
fileMenu = new QMenu(tr("&File"), this);
fileMenu->addAction(openAct);
fileMenu->addMenu(saveAsMenu);
fileMenu->addAction(printAct);
fileMenu->addSeparator();
fileMenu->addAction(exitAct);
optionMenu = new QMenu(tr("&Options"), this);
optionMenu->addAction(penColorAct);
optionMenu->addAction(penWidthAct);
optionMenu->addSeparator();
optionMenu->addAction(clearScreenAct);
helpMenu = new QMenu(tr("&Help"), this);
helpMenu->addAction(aboutAct);
helpMenu->addAction(aboutQtAct);
menuBar()->addMenu(fileMenu);
menuBar()->addMenu(optionMenu);
menuBar()->addMenu(helpMenu);
}
//! [16]
//! [17]
bool MainWindow::maybeSave()
//! [17] //! [18]
{
if (scribbleArea->isModified()) {
QMessageBox::StandardButton ret;
ret = QMessageBox::warning(this, tr("Scribble"),
tr("The image has been modified.\n"
"Do you want to save your changes?"),
QMessageBox::Save | QMessageBox::Discard
| QMessageBox::Cancel);
if (ret == QMessageBox::Save) {
return saveFile("png");
} else if (ret == QMessageBox::Cancel) {
return false;
}
}
return true;
}
//! [18]
//! [19]
bool MainWindow::saveFile(const QByteArray &fileFormat)
//! [19] //! [20]
{
QString initialPath = QDir::currentPath() + "/untitled." + fileFormat;
QString fileName = QFileDialog::getSaveFileName(this, tr("Save As"),
initialPath,
tr("%1 Files (*.%2);;All Files (*)")
.arg(QString(fileFormat.toUpper()))
.arg(QString(fileFormat)));
if (fileName.isEmpty()) {
return false;
} else {
return scribbleArea->saveImage(fileName, fileFormat);
}
}
//! [20]
|
