Make monitor detection more robust for fullscreen mode

src/dialogs/kdenlivesettingsdialog.cpp

@@ -752,30 +752,44 @@ void KdenliveSettingsDialog::initDevices()
     m_configSdl.group_sdl->setEnabled(KdenliveSettings::audiobackend().startsWith(QLatin1String("sdl")));
     
     // Fill monitors data
+    fillMonitorData();
+    connect(qApp, &QApplication::screenAdded, this, &KdenliveSettingsDialog::fillMonitorData);
+    connect(qApp, &QApplication::screenRemoved, this, &KdenliveSettingsDialog::fillMonitorData);
+    loadCurrentV4lProfileInfo();
+}
+
+
+
+void KdenliveSettingsDialog::fillMonitorData()
+{
     QSignalBlocker bk(m_configSdl.fullscreen_monitor);
     m_configSdl.fullscreen_monitor->clear();
     m_configSdl.fullscreen_monitor->addItem(i18n("auto"));
     int ix = 0;
     for (const QScreen* screen : qApp->screens()) {
-#ifdef Q_OS_WIN
-        // Screen manufacturer, model and serial don't work under Windows
-        m_configSdl.fullscreen_monitor->addItem(QString("%1: %2").arg(QString::number(ix), screen->name()), QString::number(ix));
+        QString screenName = screen->name().isEmpty() ? i18n("Monitor %1", ix + 1) : QString("%1: %2").arg(ix + 1).arg(screen->name());
+        if (!screen->model().isEmpty()) {
+            screenName.append(QString(" - %1").arg(screen->model()));
+        }
+        if (!screen->manufacturer().isEmpty()) {
+            screenName.append(QString(" (%1)").arg(screen->manufacturer()));
+        }
+        m_configSdl.fullscreen_monitor->addItem(screenName, QString("%1:%2").arg(QString::number(ix), screen->serialNumber()));
         ix++;
-#else
-        m_configSdl.fullscreen_monitor->addItem(QString("%1 %2 (%3)").arg(screen->manufacturer(), screen->model(), screen->name()), screen->serialNumber());
-#endif
-
     }
     if (!KdenliveSettings::fullscreen_monitor().isEmpty()) {
         int ix = m_configSdl.fullscreen_monitor->findData(KdenliveSettings::fullscreen_monitor());
         if (ix > -1) {
             m_configSdl.fullscreen_monitor->setCurrentIndex(ix);
+        } else {
+            // Monitor not found, reset
+            m_configSdl.fullscreen_monitor->setCurrentIndex(0);
+            KdenliveSettings::setFullscreen_monitor(QString());
         }
     }
-
-    loadCurrentV4lProfileInfo();
 }
 
+
 void KdenliveSettingsDialog::slotReadAudioDevices()
 {
     QString result = QString(m_readProcess.readAllStandardOutput());

src/dialogs/kdenlivesettingsdialog.h

@@ -98,6 +98,8 @@ private slots:
     void downloadModelFinished(KJob* job);
     void processArchive(const QString &path);
     void doShowSpeechMessage(const QString &message, int messageType);
+    /** @brief fill list of connected monitors */
+    void fillMonitorData();
     
 private:
     KPageWidgetItem *m_page1;

src/monitor/monitor.cpp

@@ -991,13 +991,15 @@ void Monitor::slotSwitchFullScreen(bool minimizeOnly)
             bool screenFound = false;
             int ix = -1;
             if (!KdenliveSettings::fullscreen_monitor().isEmpty()) {
+                // If the platform does now provide screen serial number, use indexes
                 for (const QScreen* screen : qApp->screens()) {
-#ifdef Q_OS_WIN
                     ix++;
-                    if (QString::number(ix) == KdenliveSettings::fullscreen_monitor()) {
-#else
-                    if (screen->serialNumber() == KdenliveSettings::fullscreen_monitor()) {
-#endif
+                    bool match = KdenliveSettings::fullscreen_monitor() == QString("%1:%2").arg(QString::number(ix),screen->serialNumber());
+                    // Check if monitor's index changed
+                    if (!match && !screen->serialNumber().isEmpty()) {
+                        match = KdenliveSettings::fullscreen_monitor().section(QLatin1Char(':'), 1) == screen->serialNumber();
+                    }
+                    if (match) {
                         // Match
                         m_glWidget->setParent(nullptr);
                         m_glWidget->move(screen->geometry().topLeft());