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fix: Fix scanner no devices issue. #21

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Merged
lzwind merged 1 commit into from
Jul 18, 2025
Merged

fix: Fix scanner no devices issue. #21

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54 changes: 40 additions & 14 deletions src/device/scannerdevice.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -80,7 +80,7 @@
// 2 print normal messages
// 3 print debugging messages
// 4 print everything
QString logLevel = "1";
QString logLevel = "2";
#ifdef QT_DEBUG
logLevel = "2";
#endif
Expand All @@ -97,10 +97,11 @@
ScannerDevice::~ScannerDevice()
{
#ifndef _WIN32
qCInfo(app) << "🔥 ScannerDevice destructor called - this should NOT happen during device list refresh!";
closeDevice(); // Ensure device is closed if open

Check warning on line 101 in src/device/scannerdevice.cpp

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Virtual function 'closeDevice' is called from destructor '~ScannerDevice()' at line 101. Dynamic binding is not used.
if (m_saneInitialized) {
sane_exit();
qCDebug(app) << "SANE backend exited successfully";
qCInfo(app) << "SANE backend exited from destructor";
}
#endif
}
Expand Down Expand Up @@ -140,17 +141,28 @@
return deviceNames;
}


// Try calling sane_get_devices with different parameters
qCDebug(app) << "Attempting to get device list (include network devices)";
const SANE_Device **device_list = nullptr;
SANE_Status status = sane_get_devices(&device_list, SANE_TRUE);

// First attempt: Get ALL devices including network devices (ESCL/AirScan)
qCDebug(app) << "First attempt: Getting ALL devices (including network devices)";
SANE_Status status = sane_get_devices(&device_list, SANE_FALSE);
qCDebug(app) << "Device list status:" << sane_strstatus(status);

if (status != SANE_STATUS_GOOD || !device_list) {
qCDebug(app) << "Retrying device list (local devices only)";
// If first attempt fails or returns no devices, wait and retry
// This is especially important for network devices (ESCL/AirScan) which need discovery time
if (status != SANE_STATUS_GOOD || !device_list || (device_list && !device_list[0])) {

Check warning on line 153 in src/device/scannerdevice.cpp

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Condition 'device_list' is always true
qCInfo(app) << "First attempt returned no devices, waiting for network discovery...";
QThread::msleep(2000); // Wait 2 seconds for network device discovery

qCDebug(app) << "Retrying: Getting ALL devices (including network devices)";
status = sane_get_devices(&device_list, SANE_FALSE);
qCDebug(app) << "Device list retry status:" << sane_strstatus(status);

if (status != SANE_STATUS_GOOD || !device_list || (device_list && !device_list[0])) {

Check warning on line 161 in src/device/scannerdevice.cpp

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Condition 'device_list' is always true
qCDebug(app) << "Still no devices, trying local devices only";
status = sane_get_devices(&device_list, SANE_TRUE);
qCDebug(app) << "Local devices only status:" << sane_strstatus(status);
}
}

if (status != SANE_STATUS_GOOD) {
Expand Down Expand Up @@ -193,14 +205,22 @@
}

qCDebug(app) << "Enumerating available scanner devices";
int deviceCount = 0;

// First count devices
for (int i = 0; device_list[i] != nullptr; ++i) {
deviceCount++;
}
qCInfo(app) << "Found" << deviceCount << "SANE devices total";

for (int i = 0; device_list[i] != nullptr; ++i) {
const SANE_Device *dev = device_list[i];
if (dev) {
qCDebug(app) << "Device found:";
qCDebug(app) << " Name:" << (dev->name ? dev->name : "null");
qCDebug(app) << " Vendor:" << (dev->vendor ? dev->vendor : "null");
qCDebug(app) << " Model:" << (dev->model ? dev->model : "null");
qCDebug(app) << " Type:" << (dev->type ? dev->type : "null");
qCInfo(app) << "Device" << (i+1) << "/" << deviceCount << ":";
qCInfo(app) << " Name:" << (dev->name ? dev->name : "null");
qCInfo(app) << " Vendor:" << (dev->vendor ? dev->vendor : "null");
qCInfo(app) << " Model:" << (dev->model ? dev->model : "null");
qCInfo(app) << " Type:" << (dev->type ? dev->type : "null");

if (dev->name) {
deviceNames.append(QString::fromUtf8(dev->name));
Expand All @@ -211,10 +231,16 @@
.arg(dev->model ? QString::fromUtf8(dev->model) : "Unknown")
.arg(dev->type ? QString::fromUtf8(dev->type) : "Unknown");

qCDebug(app) << "Added device:" << dev->name << "-" << deviceInfo;
qCInfo(app) << "✅ Successfully added device:" << dev->name << "-" << deviceInfo;
} else {
qCWarning(app) << "❌ Device has null name, skipping";
}
} else {
qCWarning(app) << "❌ Device at index" << i << "is null";
}
}

qCInfo(app) << "Final device list contains" << deviceNames.size() << "devices:" << deviceNames;

#if ADD_TEST_DEVICE
// If no devices found, add a virtual test device
Expand Down
31 changes: 24 additions & 7 deletions src/mainwindow.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -27,9 +27,10 @@ MainWindow::MainWindow(QWidget *parent)
: DMainWindow(parent)
{
// --- Initialize Devices ---
QSharedPointer<ScannerDevice> scannerDevice(new ScannerDevice(this));
// Note: Don't pass 'this' as parent when using QSharedPointer to avoid double-deletion
QSharedPointer<ScannerDevice> scannerDevice(new ScannerDevice(nullptr));
scannerDevice->initialize();
QSharedPointer<WebcamDevice> webcamDevice(new WebcamDevice(this));
QSharedPointer<WebcamDevice> webcamDevice(new WebcamDevice(nullptr));
webcamDevice->initialize();

// Store devices in map
Expand Down Expand Up @@ -106,14 +107,30 @@ void MainWindow::updateDeviceList()
auto webcam = qSharedPointerCast<WebcamDevice>(m_devices["webcam"]);

if (scanner && webcam) {
// 更新ScannersWidget中的设备列表
m_scannersWidget->updateDeviceList(scanner, webcam);
// 给网络设备发现预留更多时间（特别是首次启动）
static bool firstRun = true;
int delay = firstRun ? 3000 : 500; // 首次启动等待3秒，后续等待0.5秒

if (firstRun) {
qCInfo(app) << "First device list update, allowing extra time for network device discovery...";
firstRun = false;
}

// 使用定时器延迟更新设备列表
QTimer::singleShot(delay, this, [this]() {
// 重新获取设备指针，避免捕获过期指针
auto scanner = qSharedPointerCast<ScannerDevice>(m_devices["scanner"]);
auto webcam = qSharedPointerCast<WebcamDevice>(m_devices["webcam"]);

if (scanner && webcam) {
m_scannersWidget->updateDeviceList(scanner, webcam);
}
QTimer::singleShot(500, this, &MainWindow::hideLoading);
});
} else {
qDebug(app) << "Error: Failed to cast device pointers";
QTimer::singleShot(500, this, &MainWindow::hideLoading);
}


QTimer::singleShot(500, this, &MainWindow::hideLoading);
}

void MainWindow::showScanView(const QString &device, bool isScanner)
Expand Down