src/gui/CMakeLists.txt

@@ -29,7 +29,7 @@ set(GUI_SOURCES
 
 add_executable(kima2 ${GUI_SOURCES})
 target_include_directories(kima2 PRIVATE ${PROJECT_BINARY_DIR})
-target_link_libraries(kima2 core printer Qt5::Widgets Qt5::PrintSupport stdc++fs)
+target_link_libraries(kima2 core Qt5::Widgets Qt5::PrintSupport stdc++fs)
 if(WIN32)
     set_target_properties(kima2 PROPERTIES LINK_FLAGS "-mwindows")
 endif(WIN32)

src/gui/settingsdialog.cpp

@@ -1,7 +1,6 @@
 #include "settingsdialog.h"
 
 #include <database.h>
-#include <posprinter.h>
 
 #include <QMessageBox>
 #include <QSettings>
@@ -20,12 +19,6 @@ SettingsDialog::SettingsDialog(QWidget* parent, Qt::WindowFlags f) : QDialog(par
     ui_.posPrinterDeviceEdit->setText(posPrinterDevice);
     ui_.feePercentSpinBox->setValue(feeInPercent);
     ui_.maxFeeSpinBox->setValue(maxFeeInEuro);
-
-    connect(ui_.testPosPrinterButton, &QPushButton::clicked, this, [](){
-        //PosPrinter::initialize({0, 0});
-        PosPrinter printer;
-        printer.printTest();
-    });
 }
 
 void SettingsDialog::accept()

src/printer/CMakeLists.txt

@@ -5,5 +5,5 @@ set(PRINTER_SOURCES
 )
 
 add_library(printer STATIC ${PRINTER_SOURCES})
-target_link_libraries(printer ${LIBUSB_1_LIBRARIES})
+target_link_libraries(printer ${LibUSB_LIBRARY})
 target_include_directories(printer PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})

src/printer/posprinter.cpp

@@ -2,18 +2,11 @@
 
 #include <exception>
 #include <iostream>
-#include <sstream>
 #include <string>
 
-const std::string PosPrinter::Command::RESET = {0x1b, 0x40};
-const std::string PosPrinter::Command::ENCODING = {'\x1b', '\x74', 16};
-const std::string PosPrinter::Command::CENTERING = {'\x1b', '\x61', '\x01'};
-const std::string PosPrinter::Command::FONT_SIZE_BIG = {'\x1b', '\x21', '\x10'};
-const std::string PosPrinter::Command::FONT_SIZE_NORMAL = {'\x1b', '\x21', '\x00'};
-const std::string PosPrinter::Command::LEFT_ALIGN = {'\x1b', '\x61', '\x00'};
-const std::string PosPrinter::Command::FEED = {0x1b, 0x64, 0x03};
+PosPrinter::PosPrinter() : PosPrinter(std::pair<int, int>{0x0456, 0x0808}) {}
 
-PosPrinter::PosPrinter()
+PosPrinter::PosPrinter(std::pair<int, int> vendorModelId)
 {
     int retValue;
 
@@ -22,50 +15,17 @@ PosPrinter::PosPrinter()
         throw std::runtime_error("Init error");
     }
 
-    libusb_device** devList;
-    int devCount = libusb_get_device_list(contextPtr_, &devList);
-    if (devCount <= 0) {
-        libusb_exit(contextPtr_);
-        throw std::runtime_error("Could not receive device list");
-    }
-    int numDevice = -1;
-    for (int i = 0; i < devCount; ++i) {
-        libusb_device_descriptor desc;
-        libusb_get_device_descriptor(devList[i], &desc);
-        for (const auto& supported : supportedPrinters_.models) {
-            if (desc.idVendor == supported.first && desc.idProduct == supported.second) {
-                numDevice = i;
-                break;
-            }
-        }
-    }
+    // libusb_set_debug(contextPtr_, 3); // set verbosity level to 3, as suggested in the
+    // documentation
 
-    if (numDevice < 0) {
-        libusb_exit(contextPtr_);
-        return;
-    }
-
-    retValue = libusb_open(devList[numDevice], &devicePtr_); // these are vendorID and productID
-    if (retValue != 0) {
-        libusb_free_device_list(devList, 1);
-        libusb_exit(contextPtr_);
+    devicePtr_ =
+        libusb_open_device_with_vid_pid(contextPtr_, vendorModelId.first,
+                                        vendorModelId.second); // these are vendorID and productID
+    if (devicePtr_ == NULL) {
         throw std::runtime_error("Cannot open printer device");
     }
 
-    if (libusb_kernel_driver_active(devicePtr_, 0) == 1) { // find out if kernel driver is attached
-        std::cout << "Kernel driver active" << std::endl;
-        if (libusb_detach_kernel_driver(devicePtr_, 0) == 0) // detach it
-            std::cout << "Kernel driver detached!" << std::endl;
-    }
-
-    retValue = libusb_claim_interface(
-        devicePtr_, 0); // claim interface 0 (the first) of device (mine had jsut 1)
-    if (retValue < 0) {
-        std::cout << "Cannot claim printer interface" << std::endl;
-        throw std::runtime_error("Cannot claim printer interface");
-    }
-
-    libusb_free_device_list(devList, 1);
+    // ...
 }
 
 PosPrinter::~PosPrinter()
@@ -73,47 +33,22 @@ PosPrinter::~PosPrinter()
     int retValue;
     retValue = libusb_release_interface(devicePtr_, 0); // release the claimed interface
     if (retValue != 0) {
-        std::cout << "Cannot release printer interface" << std::endl;
+        std::cout << "Cannot Release Interface" << std::endl;
     } else {
-        std::cout << "Printer interface released" << std::endl;
+        std::cout << "Released Interface" << std::endl;
     }
 
     libusb_close(devicePtr_); // close the device we opened
     libusb_exit(contextPtr_); // close the session
+
+    delete instance_;
 }
 
-void PosPrinter::write(const std::string& text)
+void PosPrinter::initialize(std::pair<int, int> vendorModelId)
 {
-    if (devicePtr_ == NULL)
-        return;
-    int length = text.length();
-    int actual{0};
-    int retValue = libusb_bulk_transfer(devicePtr_, (0x03 | LIBUSB_ENDPOINT_OUT),
-                                        (unsigned char*)text.c_str(), length, &actual, 10000);
-    if (retValue != 0 || actual != length)
-        std::cerr << "Write Error" << std::endl;
+    if (!instance_) {
+        instance_ = new PosPrinter(vendorModelId);
+    }
 }
 
-void PosPrinter::printHeader()
-{
-    std::stringstream commandStream;
-
-    commandStream << Command::RESET << Command::ENCODING << Command::CENTERING
-                  << Command::FONT_SIZE_BIG;
-    commandStream << "Kindersachenmarkt\nDettingen\n\n";
-    commandStream << Command::LEFT_ALIGN << Command::Command::FONT_SIZE_NORMAL;
-
-    write(commandStream.str());
-}
-
-void PosPrinter::printTest()
-{
-    using namespace std::string_literals;
-    std::stringstream commandStream;
-    commandStream << Command::ENCODING;
-    commandStream << "Der Drucker kann von KIMA2\nangesprochen werden.\n\n"
-                  << "Beachten Sie, dass nicht\nalle Modelle Strichcodes\nausdrucken können.";
-    commandStream << Command::FEED;
-    printHeader();
-    write(commandStream.str());
-}
+PosPrinter* PosPrinter::getInstance() { return instance_; }

src/printer/posprinter.h

@@ -5,37 +5,18 @@
 
 #include <libusb-1.0/libusb.h>
 
-struct SupportedPrinters {
-    std::array<std::pair<int, int>, 2> models{
-        // {Vendor ID, Model ID}
-        std::make_pair(0x0456, 0x0808),
-        std::make_pair(0x0416, 0x5011),
-    };
-};
-
 class PosPrinter
 {
   public:
-    PosPrinter();
-    ~PosPrinter();
-    void write(const std::string& text);
-    void printHeader();
-    void printTest();
-
-    struct Command {
-        static const std::string RESET;
-        static const std::string ENCODING;
-        static const std::string CENTERING;
-        static const std::string FONT_SIZE_BIG;
-        static const std::string FONT_SIZE_NORMAL;
-        static const std::string LEFT_ALIGN;
-        static const std::string FEED;
-    };
-
+    static void initialize(std::pair<int, int> vendorModelIds);
+    static PosPrinter* getInstance();
   private:
+    PosPrinter();
+    PosPrinter(std::pair<int, int> vendorModelId);
+    ~PosPrinter();
+    static PosPrinter* instance_;
     libusb_context* contextPtr_{};
     libusb_device_handle* devicePtr_{};
-    SupportedPrinters supportedPrinters_;
 };
 
 #endif