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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

4,124 bytes · SHA-256 9f140df326652eac… · View upstream ↗

1// Copyright (c) 2011-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#include <qt/qrimagewidget.h>
6
7#include <qt/guiutil.h>
8
9#include <QApplication>
10#include <QClipboard>
11#include <QDrag>
12#include <QFontDatabase>
13#include <QMenu>
14#include <QMimeData>
15#include <QMouseEvent>
16#include <QPainter>
17
18#include <bitcoin-build-config.h> // IWYU pragma: keep
19
20#ifdef USE_QRCODE
21#include <qrencode.h>
22#endif
23
24QRImageWidget::QRImageWidget(QWidget* parent)
25    : QLabel(parent)
26{
27    contextMenu = new QMenu(this);
28    contextMenu->addAction(tr("&Save Image…"), this, &QRImageWidget::saveImage);
29    contextMenu->addAction(tr("&Copy Image"), this, &QRImageWidget::copyImage);
30}
31
32bool QRImageWidget::setQR(const QString& data, const QString& text)
33{
34#ifdef USE_QRCODE
35    setText("");
36    if (data.isEmpty()) return false;
37
38    // limit length
39    if (data.length() > MAX_URI_LENGTH) {
40        setText(tr("Resulting URI too long, try to reduce the text for label / message."));
41        return false;
42    }
43
44    QRcode *code = QRcode_encodeString(data.toUtf8().constData(), 0, QR_ECLEVEL_L, QR_MODE_8, 1);
45
46    if (!code) {
47        setText(tr("Error encoding URI into QR Code."));
48        return false;
49    }
50
51    QImage qrImage = QImage(code->width + 8, code->width + 8, QImage::Format_RGB32);
52    qrImage.fill(0xffffff);
53    unsigned char *p = code->data;
54    for (int y = 0; y < code->width; ++y) {
55        for (int x = 0; x < code->width; ++x) {
56            qrImage.setPixel(x + 4, y + 4, ((*p & 1) ? 0x0 : 0xffffff));
57            ++p;
58        }
59    }
60    QRcode_free(code);
61
62    const int qr_image_size = QR_IMAGE_SIZE + (text.isEmpty() ? 0 : 2 * QR_IMAGE_MARGIN);
63    QImage qrAddrImage(qr_image_size, qr_image_size, QImage::Format_RGB32);
64    qrAddrImage.fill(0xffffff);
65    {
66        QPainter painter(&qrAddrImage);
67        painter.drawImage(QR_IMAGE_MARGIN, 0, qrImage.scaled(QR_IMAGE_SIZE, QR_IMAGE_SIZE));
68
69        if (!text.isEmpty()) {
70            QRect paddedRect = qrAddrImage.rect();
71            paddedRect.setHeight(QR_IMAGE_SIZE + QR_IMAGE_TEXT_MARGIN);
72
73            QFont font = GUIUtil::fixedPitchFont();
74            font.setStretch(QFont::SemiCondensed);
75            font.setLetterSpacing(QFont::AbsoluteSpacing, 1);
76            const qreal font_size = GUIUtil::calculateIdealFontSize(paddedRect.width() - 2 * QR_IMAGE_TEXT_MARGIN, text, font);
77            font.setPointSizeF(font_size);
78
79            painter.setFont(font);
80            painter.drawText(paddedRect, Qt::AlignBottom | Qt::AlignCenter, text);
81        }
82    }
83
84    setPixmap(QPixmap::fromImage(qrAddrImage));
85
86    return true;
87#else
88    setText(tr("QR code support not available."));
89    return false;
90#endif
91}
92
93QImage QRImageWidget::exportImage()
94{
95    if (!GUIUtil::HasPixmap(this)) {
96        return QImage();
97    }
98
99    return this->pixmap(Qt::ReturnByValue).toImage();
100}
101
102void QRImageWidget::mousePressEvent(QMouseEvent *event)
103{
104    if (event->button() == Qt::LeftButton && GUIUtil::HasPixmap(this)) {
105        event->accept();
106        QMimeData *mimeData = new QMimeData;
107        mimeData->setImageData(exportImage());
108
109        QDrag *drag = new QDrag(this);
110        drag->setMimeData(mimeData);
111        drag->exec();
112    } else {
113        QLabel::mousePressEvent(event);
114    }
115}
116
117void QRImageWidget::saveImage()
118{
119    if (!GUIUtil::HasPixmap(this))
120        return;
121    QString fn = GUIUtil::getSaveFileName(
122        this, tr("Save QR Code"), QString(),
123        /*: Expanded name of the PNG file format.
124            See: https://en.wikipedia.org/wiki/Portable_Network_Graphics. */
125        tr("PNG Image") + QLatin1String(" (*.png)"), nullptr);
126    if (!fn.isEmpty())
127    {
128        exportImage().save(fn);
129    }
130}
131
132void QRImageWidget::copyImage()
133{
134    if (!GUIUtil::HasPixmap(this))
135        return;
136    QApplication::clipboard()->setImage(exportImage());
137}
138
139void QRImageWidget::contextMenuEvent(QContextMenuEvent *event)
140{
141    if (!GUIUtil::HasPixmap(this))
142        return;
143    contextMenu->exec(event->globalPos());
144}
145

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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