bitcoin/src/qt/qrimagewidget.cpp
2019-05-02 12:18:18 +00:00

141 lines
3.8 KiB
C++

// Copyright (c) 2011-2018 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <qt/qrimagewidget.h>
#include <qt/guiutil.h>
#include <QApplication>
#include <QClipboard>
#include <QDrag>
#include <QMenu>
#include <QMimeData>
#include <QMouseEvent>
#include <QPainter>
#if defined(HAVE_CONFIG_H)
#include <config/bitcoin-config.h> /* for USE_QRCODE */
#endif
#ifdef USE_QRCODE
#include <qrencode.h>
#endif
QRImageWidget::QRImageWidget(QWidget *parent):
QLabel(parent), contextMenu(nullptr)
{
contextMenu = new QMenu(this);
QAction *saveImageAction = new QAction(tr("&Save Image..."), this);
connect(saveImageAction, &QAction::triggered, this, &QRImageWidget::saveImage);
contextMenu->addAction(saveImageAction);
QAction *copyImageAction = new QAction(tr("&Copy Image"), this);
connect(copyImageAction, &QAction::triggered, this, &QRImageWidget::copyImage);
contextMenu->addAction(copyImageAction);
}
bool QRImageWidget::setQR(const QString& data, const QString& text)
{
#ifdef USE_QRCODE
setText("");
if (data.isEmpty()) return false;
// limit length
if (data.length() > MAX_URI_LENGTH) {
setText(tr("Resulting URI too long, try to reduce the text for label / message."));
return false;
}
QRcode *code = QRcode_encodeString(data.toUtf8().constData(), 0, QR_ECLEVEL_L, QR_MODE_8, 1);
if (!code) {
setText(tr("Error encoding URI into QR Code."));
return false;
}
QImage qrImage = QImage(code->width + 8, code->width + 8, QImage::Format_RGB32);
qrImage.fill(0xffffff);
unsigned char *p = code->data;
for (int y = 0; y < code->width; ++y) {
for (int x = 0; x < code->width; ++x) {
qrImage.setPixel(x + 4, y + 4, ((*p & 1) ? 0x0 : 0xffffff));
++p;
}
}
QRcode_free(code);
QImage qrAddrImage = QImage(QR_IMAGE_SIZE, QR_IMAGE_SIZE + (text.isEmpty() ? 0 : 20), QImage::Format_RGB32);
qrAddrImage.fill(0xffffff);
QPainter painter(&qrAddrImage);
painter.drawImage(0, 0, qrImage.scaled(QR_IMAGE_SIZE, QR_IMAGE_SIZE));
if (!text.isEmpty()) {
QFont font = GUIUtil::fixedPitchFont();
QRect paddedRect = qrAddrImage.rect();
// calculate ideal font size
qreal font_size = GUIUtil::calculateIdealFontSize(paddedRect.width() - 20, text, font);
font.setPointSizeF(font_size);
painter.setFont(font);
paddedRect.setHeight(QR_IMAGE_SIZE+12);
painter.drawText(paddedRect, Qt::AlignBottom|Qt::AlignCenter, text);
}
painter.end();
setPixmap(QPixmap::fromImage(qrAddrImage));
return true;
#else
setText(tr("QR code support not available."));
return false;
#endif
}
QImage QRImageWidget::exportImage()
{
if(!pixmap())
return QImage();
return pixmap()->toImage();
}
void QRImageWidget::mousePressEvent(QMouseEvent *event)
{
if(event->button() == Qt::LeftButton && pixmap())
{
event->accept();
QMimeData *mimeData = new QMimeData;
mimeData->setImageData(exportImage());
QDrag *drag = new QDrag(this);
drag->setMimeData(mimeData);
drag->exec();
} else {
QLabel::mousePressEvent(event);
}
}
void QRImageWidget::saveImage()
{
if(!pixmap())
return;
QString fn = GUIUtil::getSaveFileName(this, tr("Save QR Code"), QString(), tr("PNG Image (*.png)"), nullptr);
if (!fn.isEmpty())
{
exportImage().save(fn);
}
}
void QRImageWidget::copyImage()
{
if(!pixmap())
return;
QApplication::clipboard()->setImage(exportImage());
}
void QRImageWidget::contextMenuEvent(QContextMenuEvent *event)
{
if(!pixmap())
return;
contextMenu->exec(event->globalPos());
}