/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** 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 The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** BSD License Usage ** Alternatively, 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 The Qt Company Ltd 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 #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(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::getInt(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("

The Scribble 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:

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.

The example also demonstrates " "how to use QPainter to draw an image in real time, as well as " "to repaint widgets.

")); } //! [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::fromLatin1(fileFormat.toUpper())) .arg(QString::fromLatin1(fileFormat))); if (fileName.isEmpty()) { return false; } else { return scribbleArea->saveImage(fileName, fileFormat.constData()); } } //! [20]