exportdialog.cpp Example File
svgviewer/exportdialog.cpp
#include "exportdialog.h"
#include <QApplication>
#include <QDesktopWidget>
#include <QDialogButtonBox>
#include <QFileDialog>
#include <QFormLayout>
#include <QHBoxLayout>
#include <QMessageBox>
#include <QLabel>
#include <QLineEdit>
#include <QPushButton>
#include <QSpinBox>
#include <QToolButton>
#include <QVBoxLayout>
#include <QImageWriter>
#include <QDebug>
#include <QDir>
#include <QFileInfo>
enum { exportMinimumSize = 1, exportMaximumSize = 2000 };
ExportDialog::ExportDialog(QWidget *parent)
: QDialog(parent)
, m_fileNameLineEdit(new QLineEdit(this))
, m_widthSpinBox(new QSpinBox(this))
, m_heightSpinBox(new QSpinBox(this))
, m_aspectRatio(1)
{
typedef void (QSpinBox::*QSpinBoxIntSignal)(int);
setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);
setWindowTitle(tr("Export"));
QFormLayout *formLayout = new QFormLayout(this);
QHBoxLayout *fileLayout = new QHBoxLayout;
fileLayout->addWidget(m_fileNameLineEdit);
m_fileNameLineEdit->setMinimumWidth(QApplication::desktop()->availableGeometry(this).width() / 6);
QPushButton *browseButton = new QPushButton(tr("Browse..."), this);
fileLayout->addWidget(browseButton);
connect(browseButton, &QAbstractButton::clicked, this, &ExportDialog::browse);
formLayout->addRow(tr("File:"), fileLayout);
QHBoxLayout *sizeLayout = new QHBoxLayout;
sizeLayout->addStretch();
m_widthSpinBox->setMinimum(exportMinimumSize);
m_widthSpinBox->setMaximum(exportMaximumSize);
connect(m_widthSpinBox, static_cast<QSpinBoxIntSignal>(&QSpinBox::valueChanged),
this, &ExportDialog::exportWidthChanged);
sizeLayout->addWidget(m_widthSpinBox);
sizeLayout->addWidget(new QLabel(tr("x")));
m_heightSpinBox->setMinimum(exportMinimumSize);
m_heightSpinBox->setMaximum(exportMaximumSize);
connect(m_heightSpinBox, static_cast<QSpinBoxIntSignal>(&QSpinBox::valueChanged),
this, &ExportDialog::exportHeightChanged);
sizeLayout->addWidget(m_heightSpinBox);
QToolButton *resetButton = new QToolButton(this);
resetButton->setIcon(QIcon(":/qt-project.org/styles/commonstyle/images/refresh-32.png"));
sizeLayout->addWidget(resetButton);
connect(resetButton, &QAbstractButton::clicked, this, &ExportDialog::resetExportSize);
formLayout->addRow(tr("Size:"), sizeLayout);
QDialogButtonBox *buttonBox = new QDialogButtonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel, this);
connect(buttonBox, &QDialogButtonBox::accepted, this, &QDialog::accept);
connect(buttonBox, &QDialogButtonBox::rejected, this, &QDialog::reject);
formLayout->addRow(buttonBox);
}
void ExportDialog::accept()
{
const QString fileName = exportFileName();
if (fileName.isEmpty()) {
QMessageBox::warning(this, windowTitle(), tr("Please enter a file name"));
return;
}
QFileInfo fi(fileName);
if (fi.exists()) {
const QString question = tr("%1 already exists.\nWould you like to overwrite it?").arg(QDir::toNativeSeparators(fileName));
if (QMessageBox::question(this, windowTitle(), question, QMessageBox::Yes | QMessageBox::No) != QMessageBox::Yes)
return;
}
QDialog::accept();
}
QSize ExportDialog::exportSize() const
{
return QSize(m_widthSpinBox->value(), m_heightSpinBox->value());
}
void ExportDialog::setExportSize(const QSize &size)
{
m_defaultSize = size;
QSizeF defaultSizeF(m_defaultSize);
m_aspectRatio = defaultSizeF.width() / defaultSizeF.height();
setExportWidthBlocked(size.width());
setExportHeightBlocked(size.height());
}
void ExportDialog::resetExportSize()
{
setExportWidthBlocked(m_defaultSize.width());
setExportHeightBlocked(m_defaultSize.height());
}
void ExportDialog::setExportWidthBlocked(int width)
{
if (m_widthSpinBox->value() != width) {
const bool blockSignals = m_widthSpinBox->blockSignals(true);
m_widthSpinBox->setValue(width);
m_widthSpinBox->blockSignals(blockSignals);
}
}
void ExportDialog::setExportHeightBlocked(int height)
{
if (m_heightSpinBox->value() != height) {
const bool blockSignals = m_heightSpinBox->blockSignals(true);
m_heightSpinBox->setValue(height);
m_heightSpinBox->blockSignals(blockSignals);
}
}
void ExportDialog::exportWidthChanged(int width)
{
const bool square = m_defaultSize.width() == m_defaultSize.height();
setExportHeightBlocked(square ? width : qRound(qreal(width) / m_aspectRatio));
}
void ExportDialog::exportHeightChanged(int height)
{
const bool square = m_defaultSize.width() == m_defaultSize.height();
setExportWidthBlocked(square ? height : qRound(qreal(height) * m_aspectRatio));
}
QString ExportDialog::exportFileName() const
{
return QDir::cleanPath(m_fileNameLineEdit->text().trimmed());
}
void ExportDialog::setExportFileName(const QString &f)
{
m_fileNameLineEdit->setText(QDir::toNativeSeparators(f));
}
void ExportDialog::browse()
{
QFileDialog fileDialog(this);
fileDialog.setAcceptMode(QFileDialog::AcceptSave);
const QString fileName = exportFileName();
if (!fileName.isEmpty())
fileDialog.setDirectory(QFileInfo(fileName).absolutePath());
QStringList mimeTypes;
const auto supportedMimeTypes = QImageWriter::supportedMimeTypes();
for (const QByteArray &mimeType : supportedMimeTypes)
mimeTypes.append(QLatin1String(mimeType));
fileDialog.setMimeTypeFilters(mimeTypes);
const int pngIndex = mimeTypes.indexOf("image/png");
if (pngIndex >= 0) {
fileDialog.selectMimeTypeFilter(mimeTypes.at(pngIndex));
fileDialog.setDefaultSuffix("png");
}
if (fileDialog.exec() == QDialog::Accepted)
setExportFileName(fileDialog.selectedFiles().constFirst());
}