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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "mainwindow.h"
#include "imagemodel.h"
#include "pixeldelegate.h"
#include <QtWidgets>
#if defined(QT_PRINTSUPPORT_LIB)
#include <QtPrintSupport/qtprintsupportglobal.h>
#if QT_CONFIG(printdialog)
#include <QPrinter>
#include <QPrintDialog>
#endif
#endif
//! [0]
MainWindow::MainWindow()
{
//! [0]
currentPath = QDir::homePath();
model = new ImageModel(this);
QWidget *centralWidget = new QWidget;
//! [1]
view = new QTableView;
view->setShowGrid(false);
view->horizontalHeader()->hide();
view->verticalHeader()->hide();
view->horizontalHeader()->setMinimumSectionSize(1);
view->verticalHeader()->setMinimumSectionSize(1);
view->setModel(model);
//! [1]
//! [2]
PixelDelegate *delegate = new PixelDelegate(this);
view->setItemDelegate(delegate);
//! [2]
//! [3]
QLabel *pixelSizeLabel = new QLabel(tr("Pixel size:"));
QSpinBox *pixelSizeSpinBox = new QSpinBox;
pixelSizeSpinBox->setMinimum(4);
pixelSizeSpinBox->setMaximum(32);
pixelSizeSpinBox->setValue(12);
//! [3]
QMenu *fileMenu = new QMenu(tr("&File"), this);
QAction *openAction = fileMenu->addAction(tr("&Open..."));
openAction->setShortcuts(QKeySequence::Open);
printAction = fileMenu->addAction(tr("&Print..."));
printAction->setEnabled(false);
printAction->setShortcut(QKeySequence::Print);
QAction *quitAction = fileMenu->addAction(tr("E&xit"));
quitAction->setShortcuts(QKeySequence::Quit);
QMenu *helpMenu = new QMenu(tr("&Help"), this);
QAction *aboutAction = helpMenu->addAction(tr("&About"));
menuBar()->addMenu(fileMenu);
menuBar()->addSeparator();
menuBar()->addMenu(helpMenu);
connect(openAction, &QAction::triggered, this, &MainWindow::chooseImage);
connect(printAction, &QAction::triggered, this, &MainWindow::printImage);
connect(quitAction, &QAction::triggered, qApp, &QCoreApplication::quit);
connect(aboutAction, &QAction::triggered, this, &MainWindow::showAboutBox);
//! [4]
connect(pixelSizeSpinBox, &QSpinBox::valueChanged,
delegate, &PixelDelegate::setPixelSize);
connect(pixelSizeSpinBox, &QSpinBox::valueChanged,
this, &MainWindow::updateView);
//! [4]
QHBoxLayout *controlsLayout = new QHBoxLayout;
controlsLayout->addWidget(pixelSizeLabel);
controlsLayout->addWidget(pixelSizeSpinBox);
controlsLayout->addStretch(1);
QVBoxLayout *mainLayout = new QVBoxLayout;
mainLayout->addWidget(view);
mainLayout->addLayout(controlsLayout);
centralWidget->setLayout(mainLayout);
setCentralWidget(centralWidget);
setWindowTitle(tr("Pixelator"));
resize(640, 480);
//! [5]
}
//! [5]
void MainWindow::chooseImage()
{
QString fileName = QFileDialog::getOpenFileName(this,
tr("Choose an image"), currentPath, "*");
if (!fileName.isEmpty())
openImage(fileName);
}
void MainWindow::openImage(const QString &fileName)
{
QImage image;
if (image.load(fileName)) {
model->setImage(image);
if (!fileName.startsWith(":/")) {
currentPath = fileName;
setWindowTitle(tr("%1 - Pixelator").arg(currentPath));
}
printAction->setEnabled(true);
updateView();
}
}
void MainWindow::printImage()
{
#if defined(QT_PRINTSUPPORT_LIB) && QT_CONFIG(printdialog)
if (model->rowCount(QModelIndex())*model->columnCount(QModelIndex()) > 90000) {
QMessageBox::StandardButton answer;
answer = QMessageBox::question(this, tr("Large Image Size"),
tr("The printed image may be very large. Are you sure that "
"you want to print it?"),
QMessageBox::Yes | QMessageBox::No);
if (answer == QMessageBox::No)
return;
}
QPrinter printer(QPrinter::HighResolution);
QPrintDialog dlg(&printer, this);
dlg.setWindowTitle(tr("Print Image"));
if (dlg.exec() != QDialog::Accepted) {
return;
}
QPainter painter;
painter.begin(&printer);
int rows = model->rowCount(QModelIndex());
int columns = model->columnCount(QModelIndex());
int sourceWidth = (columns + 1) * ItemSize;
int sourceHeight = (rows + 1) * ItemSize;
painter.save();
double xscale = printer.pageRect(QPrinter::DevicePixel).width() / double(sourceWidth);
double yscale = printer.pageRect(QPrinter::DevicePixel).height() / double(sourceHeight);
double scale = qMin(xscale, yscale);
painter.translate(printer.paperRect(QPrinter::DevicePixel).x() + printer.pageRect(QPrinter::DevicePixel).width() / 2,
printer.paperRect(QPrinter::DevicePixel).y() + printer.pageRect(QPrinter::DevicePixel).height() / 2);
painter.scale(scale, scale);
painter.translate(-sourceWidth / 2, -sourceHeight / 2);
QStyleOptionViewItem option;
QModelIndex parent = QModelIndex();
QProgressDialog progress(tr("Printing..."), tr("Cancel"), 0, rows, this);
progress.setWindowModality(Qt::ApplicationModal);
float y = ItemSize / 2;
for (int row = 0; row < rows; ++row) {
progress.setValue(row);
qApp->processEvents();
if (progress.wasCanceled())
break;
float x = ItemSize / 2;
for (int column = 0; column < columns; ++column) {
option.rect = QRect(int(x), int(y), ItemSize, ItemSize);
view->itemDelegate()->paint(&painter, option,
model->index(row, column, parent));
x = x + ItemSize;
}
y = y + ItemSize;
}
progress.setValue(rows);
painter.restore();
painter.end();
if (progress.wasCanceled()) {
QMessageBox::information(this, tr("Printing canceled"),
tr("The printing process was canceled."), QMessageBox::Cancel);
}
#else
QMessageBox::information(this, tr("Printing canceled"),
tr("Printing is not supported on this Qt build"), QMessageBox::Cancel);
#endif
}
void MainWindow::showAboutBox()
{
QMessageBox::about(this, tr("About the Pixelator example"),
tr("This example demonstrates how a standard view and a custom\n"
"delegate can be used to produce a specialized representation\n"
"of data in a simple custom model."));
}
//! [6]
void MainWindow::updateView()
{
view->resizeColumnsToContents();
view->resizeRowsToContents();
}
//! [6]
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