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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include <QtWidgets>
#include "mainwindow.h"
#include "scribblearea.h"
//! [0]
MainWindow::MainWindow()
{
scribbleArea = new ScribbleArea;
setCentralWidget(scribbleArea);
createActions();
createMenus();
setWindowTitle(tr("Finger Paint"));
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]
//! [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->setShortcut(tr("Ctrl+O"));
connect(openAct, &QAction::triggered, this, &MainWindow::open);
const QList<QByteArray> imageFormats = QImageWriter::supportedImageFormats();
for (const QByteArray &format : imageFormats) {
QString text = tr("%1...").arg(QString(format).toUpper());
QAction *action = new QAction(text, this);
action->setData(format);
connect(action, &QAction::triggered, this, &MainWindow::save);
saveAsActs.append(action);
}
printAct = new QAction(tr("&Print..."), this);
connect(printAct, &QAction::triggered, scribbleArea, &ScribbleArea::print);
exitAct = new QAction(tr("E&xit"), this);
exitAct->setShortcut(tr("Ctrl+Q"));
connect(exitAct, &QAction::triggered, this, &QWidget::close);
clearScreenAct = new QAction(tr("&Clear Screen"), this);
clearScreenAct->setShortcut(tr("Ctrl+L"));
connect(clearScreenAct, &QAction::triggered,
scribbleArea, &ScribbleArea::clearImage);
aboutAct = new QAction(tr("&About"), this);
connect(aboutAct, &QAction::triggered, this, &MainWindow::about);
aboutQtAct = new QAction(tr("About &Qt"), this);
connect(aboutQtAct, &QAction::triggered, qApp, &QApplication::aboutQt);
}
//! [14]
//! [15]
void MainWindow::createMenus()
//! [15] //! [16]
{
saveAsMenu = new QMenu(tr("&Save As"), this);
saveAsMenu->addActions(saveAsActs);
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(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]
|
