zxing-cpp · UpdogCoder · Feb 18, 2024 · Feb 18, 2024
diff --git a/example/CMakeLists.txt b/example/CMakeLists.txt
@@ -56,4 +56,9 @@ if (BUILD_WRITERS)
         add_executable (ZXingQtWriter ZXingQtWriter.cpp)
         target_link_libraries(ZXingQtWriter ZXing::ZXing Qt::Gui)
     endif()
+
+    if (TARGET Qt::Multimedia AND TARGET Qt::Quick)
+            add_executable(ZXingQtQmlWriter ZXingQtQmlWriterMain.cpp ZXingQtQmlWriter.qrc ZXingQtQmlWriter.h ZXingQtQmlWriter.cpp)
+            target_link_libraries(ZXingQtQmlWriter ZXing::ZXing Qt::Gui Qt::Multimedia Qt::Quick)
+        endif()
 endif()
diff --git a/example/ZXingQtQmlWriter.cpp b/example/ZXingQtQmlWriter.cpp
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: Apache-2.0
+#include "ZXingQtQmlWriter.h"
+#include "BarcodeFormat.h"
+#include "BitMatrix.h"
+#include "MultiFormatWriter.h"
+#include <QPainter>
+#include <algorithm>
+
+ZXingQtQmlWriter::ZXingQtQmlWriter(QQuickPaintedItem* parent) : QQuickPaintedItem{parent}
+{}
+
+
+void ZXingQtQmlWriter::generateBarcode(const QString &text)
+{
+	auto writer = ZXing::MultiFormatWriter(ZXing::BarcodeFormat::QRCode);
+	auto matrix = writer.encode(text.toStdString(), 0, 0);
+	auto bitmap = ZXing::ToMatrix<uint8_t>(matrix);
+
+	m_qrCode = QImage(bitmap.data(), bitmap.width(), bitmap.height(), bitmap.width(), QImage::Format::Format_Grayscale8).copy();
+	this->update();
+}
+
+void ZXingQtQmlWriter::paint(QPainter *painter)
+{
+	//Ensuring that QR code is drawn as a rectangle
+	qreal minSize = std::min(boundingRect().width(), boundingRect().height());
+	QRectF scaledRect{0,0,minSize,minSize};
+	// Center the scaled image within the container
+	scaledRect.moveCenter(boundingRect().center());
+
+	painter->drawImage(scaledRect, m_qrCode);
+}
diff --git a/example/ZXingQtQmlWriter.h b/example/ZXingQtQmlWriter.h
@@ -0,0 +1,34 @@
+// SPDX-License-Identifier: Apache-2.0
+#ifndef ZXINGQTQMLWRITER_H
+#define ZXINGQTQMLWRITER_H
+
+#include <QObject>
+#include <QQuickPaintedItem>
+#include <QQmlEngine>
+#include <QImage>
+
+//Example of class which can draw QR code in QML based on
+//QImage generated by ZXing
+class ZXingQtQmlWriter : public QQuickPaintedItem
+{
+	Q_OBJECT
+	QML_ELEMENT
+
+public:
+	explicit ZXingQtQmlWriter(QQuickPaintedItem* parent = nullptr);
+
+	//Method based on code from ZXingQtWriter.cpp created by Axel Waggershauser.
+	//Method uses ZXing::BarcodeFormat::QRCode format - different formats can be
+	//supported by passing the format as argument or changing format inside method
+	//implementation
+	Q_INVOKABLE void generateBarcode(const QString &text);
+
+	// QQuickPaintedItem interface
+	void paint(QPainter *painter);
+
+private:
+	QImage m_qrCode;
+};
+
+
+#endif // ZXINGQTQMLWRITER_H
diff --git a/example/ZXingQtQmlWriter.qml b/example/ZXingQtQmlWriter.qml
@@ -0,0 +1,50 @@
+import QtQuick 2.15
+import QtQuick.Controls 2.15
+import QtQuick.Layouts 2.15
+import ZXing 1.0
+
+ApplicationWindow {
+    id: app
+    visible: true
+    width: 480
+    height: 640
+    title: Qt.application.name
+
+    background: Rectangle {
+        color: "#2e2f30"
+    }
+
+    ColumnLayout {
+        id: appLayout
+        anchors.fill: parent
+        //Creating instance of ZXingQtQmlWriter that displays QR code
+        ZXingQtQmlWriter {
+            id: qrCode
+
+            Layout.fillHeight: true
+            Layout.fillWidth: true
+            Layout.margins: 25
+            Layout.alignment: Qt.AlignTop | Qt.AlignHCenter
+        }
+
+        RowLayout {
+            Layout.margins: 50
+            Layout.alignment: Qt.AlignTop
+
+            TextField {
+                id: codeContentsInput
+                Layout.fillWidth: true
+                Layout.alignment: Qt.AlignHCenter
+
+                placeholderText: "Enter contents of QR code"
+                onAccepted: qrCode.generateBarcode(codeContentsInput.text)
+            }
+
+            Button {
+                Layout.alignment: Qt.AlignHCenter
+                text: "Generate"
+                onClicked: qrCode.generateBarcode(codeContentsInput.text)
+            }
+        }
+    }
+}
diff --git a/example/ZXingQtQmlWriter.qrc b/example/ZXingQtQmlWriter.qrc
@@ -0,0 +1,5 @@
+<RCC>
+    <qresource prefix="/">
+        <file>ZXingQtQmlWriter.qml</file>
+    </qresource>
+</RCC>
diff --git a/example/ZXingQtQmlWriterMain.cpp b/example/ZXingQtQmlWriterMain.cpp
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2020 Axel Waggershauser
+ */
+// SPDX-License-Identifier: Apache-2.0
+
+#include <QGuiApplication>
+#include <QQmlApplicationEngine>
+
+#include "ZXingQtQmlWriter.h"
+
+int main(int argc, char *argv[])
+{
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
+	QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
+#endif
+	QGuiApplication app(argc, argv);
+	app.setApplicationName("ZXingQtQmlWriter");
+
+	ZXingQtQmlWriter writer;
+	//Registering ZXingQtQmlWriter instance so it is created on QML level.
+	//Can be done directly inside CMake using qt_add_qml_module macro
+	qmlRegisterType<ZXingQtQmlWriter>("ZXing",1,0, "ZXingQtQmlWriter");
+
+	QQmlApplicationEngine engine;
+	engine.load(QUrl(QStringLiteral("qrc:/ZXingQtQmlWriter.qml")));
+	if (engine.rootObjects().isEmpty()) {
+		return -1;
+	}
+
+	return app.exec();
+}