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/*************************************************************************
* Copyright (c) 2011 AT&T Intellectual Property
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* https://www.eclipse.org/legal/epl-v10.html
*
* Contributors: Details at https://graphviz.org
*************************************************************************/
#include "imageviewer.h"
#include "mdichild.h"
#include <QtGlobal>
ImageViewer::ImageViewer()
{
imageLabel = new QLabel;
imageLabel->setBackgroundRole(QPalette::Base);
imageLabel->setSizePolicy(QSizePolicy::Ignored, QSizePolicy::Ignored);
imageLabel->setScaledContents(true);
scrollArea = new QScrollArea;
scrollArea->setBackgroundRole(QPalette::Dark);
scrollArea->setWidget(imageLabel);
setCentralWidget(scrollArea);
createActions();
createMenus();
setWindowTitle(tr(""));
resize(800, 600);
setWindowIcon(QIcon(QStringLiteral(":/images/icon.png")));
}
bool ImageViewer::open(const QString &fileName)
{
if (!fileName.isEmpty()) {
QImage image(fileName);
if (image.isNull()) {
return false;
}
imageLabel->setPixmap(QPixmap::fromImage(image));
scaleFactor = 1.0;
fitToWindowAct->setEnabled(true);
updateActions();
if (!fitToWindowAct->isChecked())
imageLabel->adjustSize();
}
return true;
}
void ImageViewer::print()
{
#ifndef QT_NO_PRINTER
auto get_pixmap = [&]() {
#if QT_VERSION < QT_VERSION_CHECK(5, 15, 0)
Q_ASSERT(imageLabel->pixmap());
return *imageLabel->pixmap();
#else
return imageLabel->pixmap(Qt::ReturnByValue);
#endif
};
QPrintDialog dialog(&printer, this);
if (dialog.exec()) {
QPainter painter(&printer);
QRect rect = painter.viewport();
QSize size = get_pixmap().size();
size.scale(rect.size(), Qt::KeepAspectRatio);
painter.setViewport(rect.x(), rect.y(), size.width(),
size.height());
painter.setWindow(get_pixmap().rect());
painter.drawPixmap(0, 0, get_pixmap());
}
#endif
}
void ImageViewer::zoomIn()
{
scaleImage(1.25);
}
void ImageViewer::zoomOut()
{
scaleImage(0.8);
}
void ImageViewer::normalSize()
{
imageLabel->adjustSize();
scaleFactor = 1.0;
}
void ImageViewer::fitToWindow()
{
bool fitToWindow = fitToWindowAct->isChecked();
scrollArea->setWidgetResizable(fitToWindow);
if (!fitToWindow) {
normalSize();
}
updateActions();
}
void ImageViewer::about()
{
QMessageBox::about(this, tr("About Image Viewer"),
tr
("<p>The <b>Image Viewer</b> example shows how to combine QLabel "
"and QScrollArea to display an image. QLabel is typically used "
"for displaying a text, but it can also display an image. "
"QScrollArea provides a scrolling view around another widget. "
"If the child widget exceeds the size of the frame, QScrollArea "
"automatically provides scroll bars. </p><p>The example "
"demonstrates how QLabel's ability to scale its contents "
"(QLabel::scaledContents), and QScrollArea's ability to "
"automatically resize its contents "
"(QScrollArea::widgetResizable), can be used to implement "
"zooming and scaling features. </p><p>In addition the example "
"shows how to use QPainter to print an image.</p>"));
}
void ImageViewer::createActions()
{
printAct = new QAction(tr("&Print..."), this);
printAct->setShortcut(tr("Ctrl+P"));
printAct->setEnabled(false);
connect(printAct, &QAction::triggered, this, &ImageViewer::print);
exitAct = new QAction(tr("E&xit"), this);
exitAct->setShortcut(tr("Ctrl+Q"));
connect(exitAct, &QAction::triggered, this, &ImageViewer::close);
zoomInAct = new QAction(tr("Zoom &In (25%)"), this);
zoomInAct->setShortcut(tr("Ctrl++"));
zoomInAct->setEnabled(false);
connect(zoomInAct, &QAction::triggered, this, &ImageViewer::zoomIn);
zoomOutAct = new QAction(tr("Zoom &Out (25%)"), this);
zoomOutAct->setShortcut(tr("Ctrl+-"));
zoomOutAct->setEnabled(false);
connect(zoomOutAct, &QAction::triggered, this, &ImageViewer::zoomOut);
normalSizeAct = new QAction(tr("&Normal Size"), this);
normalSizeAct->setShortcut(tr("Ctrl+S"));
normalSizeAct->setEnabled(false);
connect(normalSizeAct, &QAction::triggered, this, &ImageViewer::normalSize);
fitToWindowAct = new QAction(tr("&Fit to Window"), this);
fitToWindowAct->setEnabled(false);
fitToWindowAct->setCheckable(true);
fitToWindowAct->setShortcut(tr("Ctrl+F"));
connect(fitToWindowAct, &QAction::triggered, this,
&ImageViewer::fitToWindow);
aboutAct = new QAction(tr("&About"), this);
connect(aboutAct, &QAction::triggered, this, &ImageViewer::about);
aboutQtAct = new QAction(tr("About &Qt"), this);
connect(aboutQtAct, &QAction::triggered, qApp, &QApplication::aboutQt);
}
void ImageViewer::createMenus()
{
viewMenu = new QMenu(tr("&View"), this);
viewMenu->addAction(zoomInAct);
viewMenu->addAction(zoomOutAct);
viewMenu->addAction(normalSizeAct);
viewMenu->addSeparator();
viewMenu->addAction(fitToWindowAct);
menuBar()->addMenu(viewMenu);
}
void ImageViewer::updateActions()
{
zoomInAct->setEnabled(!fitToWindowAct->isChecked());
zoomOutAct->setEnabled(!fitToWindowAct->isChecked());
normalSizeAct->setEnabled(!fitToWindowAct->isChecked());
}
void ImageViewer::scaleImage(double factor)
{
auto get_pixmap = [&]() {
#if QT_VERSION < QT_VERSION_CHECK(5, 15, 0)
Q_ASSERT(imageLabel->pixmap());
return *imageLabel->pixmap();
#else
return imageLabel->pixmap(Qt::ReturnByValue);
#endif
};
scaleFactor *= factor;
imageLabel->resize(scaleFactor * get_pixmap().size());
adjustScrollBar(scrollArea->horizontalScrollBar(), factor);
adjustScrollBar(scrollArea->verticalScrollBar(), factor);
zoomInAct->setEnabled(scaleFactor < 3.0);
zoomOutAct->setEnabled(scaleFactor > 0.333);
}
void ImageViewer::adjustScrollBar(QScrollBar * scrollBar, double factor)
{
scrollBar->setValue(int (factor * scrollBar->value()
+
((factor - 1) * scrollBar->pageStep() / 2)));
}
void ImageViewer::closeEvent(QCloseEvent * event)
{
this->graphWindow->previewFrm = nullptr;
event->accept();
}
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