New mavlink logging support

- Logging now always on to temp file - User prompted to save temp file after disconnect - Orphaned temp logs checked for on boot - Logs saved to new save file location - Log file starts/stops with first and last connnection

New mavlink logging support
- Logging now always on to temp file - User prompted to save temp file after disconnect - Orphaned temp logs checked for on boot - Logs saved to new save file location - Log file starts/stops with first and last connnection
6d7fb36a · Don Gagne · 84fb1ad7 · 6d7fb36a · 6d7fb36a · 6d7fb36a
Commit 6d7fb36a authored Nov 23, 2014 by Don Gagne
12 changed files
--- a/src/comm/MAVLinkProtocol.cc
+++ b/src/comm/MAVLinkProtocol.cc
@@ -30,9 +30,13 @@
 #include "QGCMAVLink.h"
 #include "QGCMAVLinkUASFactory.h"
 #include "QGC.h"
+#include "QGCCore.h"
 Q_DECLARE_METATYPE(mavlink_message_t)
+const char* MAVLinkProtocol::_tempLogFileTemplate = "FlightDataXXXXXX"; ///< Template for temporary log file
+const char* MAVLinkProtocol::_logFileExtension = "mavlink";             ///< Extension for log files
 /**
 * The default constructor will create a new MAVLink object sending heartbeats at
 * the MAVLINK_HEARTBEAT_DEFAULT_RATE to all connected links.
@@ -43,8 +47,6 @@ MAVLinkProtocol::MAVLinkProtocol() :
    m_heartbeatsEnabled(true),
    m_multiplexingEnabled(false),
    m_authEnabled(false),
-    m_loggingEnabled(false),
-    m_logfile(NULL),
    m_enable_version_check(true),
    m_paramRetransmissionTimeout(350),
    m_paramRewriteTimeout(500),
@@ -53,9 +55,17 @@ MAVLinkProtocol::MAVLinkProtocol() :
    m_actionRetransmissionTimeout(100),
    versionMismatchIgnore(false),
    systemId(QGC::defaultSystemId),
-    _should_exit(false)
+    _should_exit(false),
+    _logSuspendError(false),
+    _logSuspendReplay(false),
+    _protocolStatusMessageConnected(false),
+    _saveTempFlightDataLogConnected(false)
 {
    qRegisterMetaType<mavlink_message_t>("mavlink_message_t");
+    _tempLogFile.setFileTemplate(QString("%1/%2.%3").arg(QStandardPaths::writableLocation(QStandardPaths::TempLocation)).arg(_tempLogFileTemplate).arg(_logFileExtension));
+    _tempLogFile.setAutoRemove(false);
    m_authKey = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
    loadSettings();
@@ -88,18 +98,6 @@ void MAVLinkProtocol::loadSettings()
    enableVersionCheck(settings.value("VERSION_CHECK_ENABLED", m_enable_version_check).toBool());
    enableMultiplexing(settings.value("MULTIPLEXING_ENABLED", m_multiplexingEnabled).toBool());
-    // Only set logfile if there is a name present in settings
-    if (settings.contains("LOGFILE_NAME") && m_logfile == NULL)
-    {
-        m_logfile = new QFile(settings.value("LOGFILE_NAME").toString());
-    }
-    else if (m_logfile == NULL)
-    {
-        m_logfile = new QFile(QStandardPaths::writableLocation(QStandardPaths::HomeLocation) + "/qgroundcontrol_packetlog.mavlink");
-    }
-    // Enable logging
-    enableLogging(settings.value("LOGGING_ENABLED", m_loggingEnabled).toBool());
    // Only set system id if it was valid
    int temp = settings.value("GCS_SYSTEM_ID", systemId).toInt();
    if (temp > 0 && temp < 256)
@@ -127,17 +125,11 @@ void MAVLinkProtocol::storeSettings()
    QSettings settings;
    settings.beginGroup("QGC_MAVLINK_PROTOCOL");
    settings.setValue("HEARTBEATS_ENABLED", m_heartbeatsEnabled);
-    settings.setValue("LOGGING_ENABLED", m_loggingEnabled);
    settings.setValue("VERSION_CHECK_ENABLED", m_enable_version_check);
    settings.setValue("MULTIPLEXING_ENABLED", m_multiplexingEnabled);
    settings.setValue("GCS_SYSTEM_ID", systemId);
    settings.setValue("GCS_AUTH_KEY", m_authKey);
    settings.setValue("GCS_AUTH_ENABLED", m_authEnabled);
-    if (m_logfile)
-    {
-        // Logfile exists, store the name
-        settings.setValue("LOGFILE_NAME", m_logfile->fileName());
-    }
    // Parameter interface settings
    settings.setValue("PARAMETER_RETRANSMISSION_TIMEOUT", m_paramRetransmissionTimeout);
    settings.setValue("PARAMETER_REWRITE_TIMEOUT", m_paramRewriteTimeout);
@@ -150,16 +142,8 @@ void MAVLinkProtocol::storeSettings()
 MAVLinkProtocol::~MAVLinkProtocol()
 {
    storeSettings();
-    if (m_logfile)
-    {
+    _closeLogFile();
-        if (m_logfile->isOpen())
-        {
-            m_logfile->flush();
-            m_logfile->close();
-        }
-        delete m_logfile;
-        m_logfile = NULL;
-    }
    // Tell the thread to exit
    _should_exit = true;
@@ -192,18 +176,6 @@ void MAVLinkProtocol::run()
    }
 }
-QString MAVLinkProtocol::getLogfileName()
-{
-    if (m_logfile)
-    {
-        return m_logfile->fileName();
-    }
-    else
-    {
-        return QStandardPaths::writableLocation(QStandardPaths::HomeLocation) + "/qgroundcontrol_packetlog.mavlink";
-    }
-}
 void MAVLinkProtocol::resetMetadataForLink(const LinkInterface *link)
 {
    int linkId = link->getId();
@@ -217,17 +189,47 @@ void MAVLinkProtocol::resetMetadataForLink(const LinkInterface *link)
 void MAVLinkProtocol::linkStatusChanged(bool connected)
 {
    LinkInterface* link = qobject_cast<LinkInterface*>(QObject::sender());
+    if (link == NULL) {
+        Q_ASSERT(false);
+        return;
+    }
+    if (connected) {
+        Q_ASSERT(!_connectedLinks.contains(link));
+        _connectedLinks.append(link);
+        if (_connectedLinks.count() == 1) {
+            // This is the first link, we need to start logging
+            _startLogging();
+        }
+        // Send command to start MAVLink
+        // XXX hacky but safe
+        // Start NSH
+        const char init[] = {0x0d, 0x0d, 0x0d};
+        link->writeBytes(init, sizeof(init));
+        const char* cmd = "sh /etc/init.d/rc.usb\n";
+        link->writeBytes(cmd, strlen(cmd));
+        link->writeBytes(init, 4);
+    } else {
+        Q_ASSERT(_connectedLinks.contains(link));
+        _connectedLinks.removeOne(link);
+        if (_connectedLinks.count() == 0) {
+            // Last link is gone, close out logging
+            _stopLogging();
+        }
+    }
+    // Track the links which are connected to the protocol
+    QList<LinkInterface*> _connectedLinks;  ///< List of all links connected to protocol
+    qDebug() << "linkStatusChanged" << connected;
    if (link) {
        if (connected) {
-            // Send command to start MAVLink
-            // XXX hacky but safe
-            // Start NSH
-            const char init[] = {0x0d, 0x0d, 0x0d};
-            link->writeBytes(init, sizeof(init));
-            const char* cmd = "sh /etc/init.d/rc.usb\n";
-            link->writeBytes(cmd, strlen(cmd));
-            link->writeBytes(init, 4);
        }
    }
 }
@@ -314,8 +316,10 @@ void MAVLinkProtocol::receiveBytes(LinkInterface* link, QByteArray b)
            }
            // Log data
-            if (m_loggingEnabled && m_logfile)
-            {
+            Q_ASSERT(_logSuspendError || _logSuspendReplay || _tempLogFile.isOpen());
+            if (!_logSuspendError && !_logSuspendReplay) {
                uint8_t buf[MAVLINK_MAX_PACKET_LEN+sizeof(quint64)];
                // Write the uint64 time in microseconds in big endian format before the message.
@@ -332,11 +336,12 @@ void MAVLinkProtocol::receiveBytes(LinkInterface* link, QByteArray b)
                // Now write this timestamp/message pair to the log.
                QByteArray b((const char*)buf, len);
-                if(m_logfile->write(b) != len)
+                if(_tempLogFile.write(b) != len)
                {
                    // If there's an error logging data, raise an alert and stop logging.
-                    emit protocolStatusMessage(tr("MAVLink Logging failed"), tr("Could not write to file %1, disabling logging.").arg(m_logfile->fileName()));
+                    emit protocolStatusMessage(tr("MAVLink Logging failed"), tr("Could not write to file %1, logging disabled.").arg(_tempLogFile.fileName()));
-                    enableLogging(false);
+                    _stopLogging();
+                    _logSuspendError = true;
                }
            }
@@ -633,62 +638,6 @@ void MAVLinkProtocol::setActionRetransmissionTimeout(int ms)
    }
 }
-void MAVLinkProtocol::enableLogging(bool enabled)
-{
-    bool changed = false;
-    if (enabled != m_loggingEnabled) changed = true;
-    if (enabled)
-    {
-        if (m_logfile && m_logfile->isOpen())
-        {
-            m_logfile->flush();
-            m_logfile->close();
-        }
-        if (m_logfile)
-        {
-            if (!m_logfile->open(QIODevice::WriteOnly | QIODevice::Append))
-            {
-                emit protocolStatusMessage(tr("Opening MAVLink logfile for writing failed"), tr("MAVLink cannot log to the file %1, please choose a different file. Stopping logging.").arg(m_logfile->fileName()));
-                m_loggingEnabled = false;
-            }
-        }
-        else
-        {
-            emit protocolStatusMessage(tr("Opening MAVLink logfile for writing failed"), tr("MAVLink cannot start logging, no logfile selected."));
-        }
-    }
-    else if (!enabled)
-    {
-        if (m_logfile)
-        {
-            if (m_logfile->isOpen())
-            {
-                m_logfile->flush();
-                m_logfile->close();
-            }
-        }
-    }
-    m_loggingEnabled = enabled;
-    if (changed) emit loggingChanged(enabled);
-}
-void MAVLinkProtocol::setLogfileName(const QString& filename)
-{
-    if (!m_logfile)
-    {
-        m_logfile = new QFile(filename);
-    }
-    else
-    {
-        m_logfile->flush();
-        m_logfile->close();
-    }
-    m_logfile->setFileName(filename);
-    enableLogging(m_loggingEnabled);
-}
 void MAVLinkProtocol::enableVersionCheck(bool enabled)
 {
    m_enable_version_check = enabled;
@@ -711,3 +660,103 @@ int MAVLinkProtocol::getHeartbeatRate()
 {
    return heartbeatRate;
 }
+/// @brief Closes the log file if it is open
+bool MAVLinkProtocol::_closeLogFile(void)
+{
+    if (_tempLogFile.isOpen()) {
+        if (_tempLogFile.size() == 0) {
+            // Don't save zero byte files
+            _tempLogFile.remove();
+            return false;
+        } else {
+            _tempLogFile.flush();
+            _tempLogFile.close();
+            return true;
+        }
+    }
+    return false;
+}
+void MAVLinkProtocol::_startLogging(void)
+{
+    Q_ASSERT(!_tempLogFile.isOpen());
+    if (!_logSuspendReplay) {
+        if (!_tempLogFile.open()) {
+            emit protocolStatusMessage(tr("Opening Flight Data file for writing failed"),
+                                       tr("Unable to write to %1. Please choose a different file location.").arg(_tempLogFile.fileName()));
+            _closeLogFile();
+            _logSuspendError = true;
+            return;
+        }
+        qDebug() << "Temp log" << _tempLogFile.fileName();
+        _logSuspendError = false;
+    }
+}
+void MAVLinkProtocol::_stopLogging(void)
+{
+    if (_closeLogFile()) {
+        emit saveTempFlightDataLog(_tempLogFile.fileName());
+    }
+}
+/// @brief We override this virtual from QObject so that we can track when the
+///         protocolStatusMessage and saveTempFlightDataLog signals are connected.
+///         Once both are connected we can check for lost log files.
+void MAVLinkProtocol::connectNotify(const QMetaMethod& signal)
+{
+    if (signal == QMetaMethod::fromSignal(&MAVLinkProtocol::protocolStatusMessage)) {
+        _protocolStatusMessageConnected = true;
+        if (_saveTempFlightDataLogConnected) {
+            _checkLostLogFiles();
+        }
+    } else if (signal == QMetaMethod::fromSignal(&MAVLinkProtocol::saveTempFlightDataLog)) {
+        _saveTempFlightDataLogConnected = true;
+        if (_protocolStatusMessageConnected) {
+            _checkLostLogFiles();
+        }
+    }
+}
+/// @brief Checks the temp directory for log files which may have been left there.
+///         This could happen if QGC crashes without the temp log file being saved.
+///         Give the user an option to save these orphaned files.
+void MAVLinkProtocol::_checkLostLogFiles(void)
+{
+    QDir tempDir(QStandardPaths::writableLocation(QStandardPaths::TempLocation));
+    QString filter(QString("*.%1").arg(_logFileExtension));
+    QFileInfoList fileInfoList = tempDir.entryInfoList(QStringList(filter), QDir::Files);
+    qDebug() << "Orphaned log file count" << fileInfoList.count();
+    foreach(const QFileInfo fileInfo, fileInfoList) {
+        qDebug() << "Orphaned log file" << fileInfo.filePath();
+        if (fileInfo.size() == 0) {
+            // Delete all zero length files
+            QFile::remove(fileInfo.filePath());
+            continue;
+        }
+        // Give the user a chance to save the orphaned log file
+        emit protocolStatusMessage(tr("Found unsaved Flight Data"),
+                                   tr("This can happen if QGroundControl crashes during Flight Data collection. "
+                                      "If you want to save the unsaved Flight Data, select the file you want to save it to. "
+                                      "If you do not want to keep the Flight Data, select 'Cancel' on the next dialog."));
+        emit saveTempFlightDataLog(fileInfo.filePath());
+    }
+}
+void MAVLinkProtocol::suspendLogForReplay(bool suspend)
+{
+    // This must come through a slot so that we handle this on the right thread. This will
+    // also cause the signal to be queued behind any bytesReady signals which must be flushed
+    // out of the queue before we change suspend state.
+    Q_ASSERT(QThread::currentThread() == this);
+    _logSuspendReplay = suspend;
+}
--- a/src/comm/MAVLinkProtocol.h
+++ b/src/comm/MAVLinkProtocol.h
@@ -37,6 +37,8 @@ This file is part of the QGROUNDCONTROL project
 #include <QFile>
 #include <QMap>
 #include <QByteArray>
+#include <QTemporaryFile>
 #include "ProtocolInterface.h"
 #include "LinkInterface.h"
 #include "QGCMAVLink.h"
@@ -69,10 +71,7 @@ public:
    bool heartbeatsEnabled() const {
        return m_heartbeatsEnabled;
    }
-    /** @brief Get logging state */
-    bool loggingEnabled() const {
-        return m_loggingEnabled;
-    }
    /** @brief Get protocol version check state */
    bool versionCheckEnabled() const {
        return m_enable_version_check;
@@ -93,8 +92,6 @@ public:
    QString getAuthKey() {
        return m_authKey;
    }
-    /** @brief Get the name of the packet log file */
-    QString getLogfileName();
    /** @brief Get state of parameter retransmission */
    bool paramGuardEnabled() {
        return m_paramGuardEnabled;
@@ -140,7 +137,7 @@ public:
     * Reset the counters for all metadata for this link.
     */
    virtual void resetMetadataForLink(const LinkInterface *link);
    void run();
 public slots:
@@ -161,9 +158,6 @@ public slots:
    /** @brief Enable / disable the heartbeat emission */
    void enableHeartbeats(bool enabled);
-    /** @brief Enable/disable binary packet logging */
-    void enableLogging(bool enabled);
    /** @brief Enabled/disable packet multiplexing */
    void enableMultiplexing(bool enabled);
@@ -182,9 +176,6 @@ public slots:
    /** @brief Set parameter read timeout */
    void setActionRetransmissionTimeout(int ms);
-    /** @brief Set log file name */
-    void setLogfileName(const QString& filename);
    /** @brief Enable / disable version check */
    void enableVersionCheck(bool enabled);
@@ -203,16 +194,22 @@ public slots:
    void loadSettings();
    /** @brief Store protocol settings */
    void storeSettings();
+    /// @brief Suspend/Restart logging during replay. This must be emitted as a signal
+    ///         and not called directly in order to synchronize with the bytesReady signal
+    ///         which may be ahead of it in the signal queue.
+    void suspendLogForReplay(bool suspend);
+protected:    
+    // Override from QObject
+    virtual void connectNotify(const QMetaMethod& signal);
-protected:
    QTimer *heartbeatTimer;    ///< Timer to emit heartbeats
    int heartbeatRate;         ///< Heartbeat rate, controls the timer interval
    bool m_heartbeatsEnabled;  ///< Enabled/disable heartbeat emission
    bool m_multiplexingEnabled; ///< Enable/disable packet multiplexing
    bool m_authEnabled;        ///< Enable authentication token broadcast
    QString m_authKey;         ///< Authentication key
-    bool m_loggingEnabled;     ///< Enable/disable packet logging
-    QFile* m_logfile;           ///< Logfile
    bool m_enable_version_check; ///< Enable checking of version match of MAV and QGC
    int m_paramRetransmissionTimeout; ///< Timeout for parameter retransmission
    int m_paramRewriteTimeout;    ///< Timeout for sending re-write request
@@ -235,8 +232,6 @@ signals:
    void messageReceived(LinkInterface* link, mavlink_message_t message);
    /** @brief Emitted if heartbeat emission mode is changed */
    void heartbeatChanged(bool heartbeats);
-    /** @brief Emitted if logging is started / stopped */
-    void loggingChanged(bool enabled);
    /** @brief Emitted if multiplexing is started / stopped */
    void multiplexingChanged(bool enabled);
    /** @brief Emitted if authentication support is enabled / disabled */
@@ -272,6 +267,27 @@ signals:
     */
    void radioStatusChanged(LinkInterface* link, unsigned rxerrors, unsigned fixed, unsigned rssi, unsigned remrssi,
    unsigned txbuf, unsigned noise, unsigned remnoise);
+    /// @brief Emitted when a temporary log file is ready for saving
+    void saveTempFlightDataLog(QString tempLogfile);
+private:
+    bool _closeLogFile(void);
+    void _startLogging(void);
+    void _stopLogging(void);
+    void _checkLostLogFiles(void);
+    QList<LinkInterface*> _connectedLinks;  ///< List of all links connected to protocol
+    bool _logSuspendError;      ///< true: Logging suspended due to error
+    bool _logSuspendReplay;     ///< true: Logging suspended due to replay
+    QTemporaryFile _tempLogFile;                ///< File to log to
+    static const char* _tempLogFileTemplate;    ///< Template for temporary log file
+    static const char* _logFileExtension;       ///< Extension for log files
+    bool _protocolStatusMessageConnected;   ///< true: protocolStatusMessage signal has been connected
+    bool _saveTempFlightDataLogConnected;   ///< true: saveTempFlightDataLog signal has been connected
 };
 #endif // MAVLINKPROTOCOL_H_
--- a/src/ui/MAVLinkSettingsWidget.cc
+++ b/src/ui/MAVLinkSettingsWidget.cc
@@ -55,7 +55,6 @@ MAVLinkSettingsWidget::MAVLinkSettingsWidget(MAVLinkProtocol* protocol, QWidget
    // Initialize state
    m_ui->heartbeatCheckBox->setChecked(protocol->heartbeatsEnabled());
-    m_ui->loggingCheckBox->setChecked(protocol->loggingEnabled());
    m_ui->versionCheckBox->setChecked(protocol->versionCheckEnabled());
    m_ui->multiplexingCheckBox->setChecked(protocol->multiplexingEnabled());
    m_ui->systemIdSpinBox->setValue(protocol->getSystemId());
@@ -71,14 +70,9 @@ MAVLinkSettingsWidget::MAVLinkSettingsWidget(MAVLinkProtocol* protocol, QWidget
    // Heartbeat
    connect(protocol, SIGNAL(heartbeatChanged(bool)), m_ui->heartbeatCheckBox, SLOT(setChecked(bool)));
    connect(m_ui->heartbeatCheckBox, SIGNAL(toggled(bool)), protocol, SLOT(enableHeartbeats(bool)));
-    // Logging
-    connect(protocol, SIGNAL(loggingChanged(bool)), m_ui->loggingCheckBox, SLOT(setChecked(bool)));
-    connect(m_ui->loggingCheckBox, SIGNAL(toggled(bool)), protocol, SLOT(enableLogging(bool)));
    // Version check
    connect(protocol, SIGNAL(versionCheckChanged(bool)), m_ui->versionCheckBox, SLOT(setChecked(bool)));
    connect(m_ui->versionCheckBox, SIGNAL(toggled(bool)), protocol, SLOT(enableVersionCheck(bool)));
-    // Logfile
-    connect(m_ui->logFileButton, SIGNAL(clicked()), this, SLOT(chooseLogfileName()));
    // System ID
    connect(protocol, SIGNAL(systemIdChanged(int)), m_ui->systemIdSpinBox, SLOT(setValue(int)));
    connect(m_ui->systemIdSpinBox, SIGNAL(valueChanged(int)), protocol, SLOT(setSystemId(int)));
@@ -110,16 +104,10 @@ MAVLinkSettingsWidget::MAVLinkSettingsWidget(MAVLinkProtocol* protocol, QWidget
    // Update values
    m_ui->versionLabel->setText(tr("MAVLINK_VERSION: %1").arg(protocol->getVersion()));
-    updateLogfileName(protocol->getLogfileName());
    // Connect visibility updates
    connect(protocol, SIGNAL(versionCheckChanged(bool)), m_ui->versionLabel, SLOT(setVisible(bool)));
    m_ui->versionLabel->setVisible(protocol->versionCheckEnabled());
-    // Logging visibility
-    connect(protocol, SIGNAL(loggingChanged(bool)), m_ui->logFileLabel, SLOT(setVisible(bool)));
-    m_ui->logFileLabel->setVisible(protocol->loggingEnabled());
-    connect(protocol, SIGNAL(loggingChanged(bool)), m_ui->logFileButton, SLOT(setVisible(bool)));
-    m_ui->logFileButton->setVisible(protocol->loggingEnabled());
 //    // Multiplexing visibility
 //    connect(protocol, SIGNAL(multiplexingChanged(bool)), m_ui->multiplexingFilterCheckBox, SLOT(setVisible(bool)));
 //    m_ui->multiplexingFilterCheckBox->setVisible(protocol->multiplexingEnabled());
@@ -146,39 +134,6 @@ MAVLinkSettingsWidget::MAVLinkSettingsWidget(MAVLinkProtocol* protocol, QWidget
    m_ui->multiplexingFilterLineEdit->setVisible(false);
 }
-void MAVLinkSettingsWidget::updateLogfileName(const QString& fileName)
-{
-    QFileInfo file(fileName);
-    m_ui->logFileLabel->setText(file.fileName());
-}
-void MAVLinkSettingsWidget::chooseLogfileName()
-{
-    QString fileName = QFileDialog::getSaveFileName(this, tr("Specify MAVLink log file name"), QStandardPaths::writableLocation(QStandardPaths::DesktopLocation), tr("MAVLink Logfile (*.mavlink);;"));
-    if (!fileName.endsWith(".mavlink"))
-    {
-        fileName.append(".mavlink");
-    }
-    QFileInfo file(fileName);
-    if (file.exists() && !file.isWritable())
-    {
-        QMessageBox msgBox;
-        msgBox.setIcon(QMessageBox::Critical);
-        msgBox.setText(tr("The selected logfile is not writable"));
-        msgBox.setInformativeText(tr("Please make sure that the file %1 is writable or select a different file").arg(fileName));
-        msgBox.setStandardButtons(QMessageBox::Ok);
-        msgBox.setDefaultButton(QMessageBox::Ok);
-        msgBox.exec();
-    }
-    else
-    {
-        updateLogfileName(fileName);
-        protocol->setLogfileName(fileName);
-    }
-}
 void MAVLinkSettingsWidget::enableDroneOS(bool enable)
 {
    // Enable multiplexing

--- a/src/ui/MAVLinkSettingsWidget.h
+++ b/src/ui/MAVLinkSettingsWidget.h
@@ -18,10 +18,6 @@ public:
    ~MAVLinkSettingsWidget();
 public slots:
-    /** @brief Update the log file name display */
-    void updateLogfileName(const QString& fileName);
-    /** @brief Start the file select dialog for the log file */
-    void chooseLogfileName();
    /** @brief Enable DroneOS forwarding */
    void enableDroneOS(bool enable);

--- a/src/ui/MAVLinkSettingsWidget.ui
+++ b/src/ui/MAVLinkSettingsWidget.ui
@@ -7,35 +7,18 @@
    <x>0</x>
    <y>0</y>
    <width>431</width>
-    <height>530</height>
+    <height>442</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>Form</string>
  </property>
-  <layout class="QGridLayout" name="gridLayout" columnstretch="1,100,1">
+  <layout class="QGridLayout" name="gridLayout" columnstretch="1,0,0">
-   <item row="1" column="0" colspan="3">
+   <item row="16" column="0">
-    <widget class="QCheckBox" name="heartbeatCheckBox">
+    <spacer name="horizontalSpacer_4">
-     <property name="text">
-      <string>Emit heartbeat</string>
-     </property>
-    </widget>
-   </item>
-   <item row="6" column="0" colspan="3">
-    <widget class="QCheckBox" name="loggingCheckBox">
-     <property name="text">
-      <string>Log all MAVLink packets</string>
-     </property>
-    </widget>
-   </item>
-   <item row="8" column="0">
-    <spacer name="logFileSpacer">
     <property name="orientation">
      <enum>Qt::Horizontal</enum>
     </property>
-     <property name="sizeType">
-      <enum>QSizePolicy::MinimumExpanding</enum>
-     </property>
     <property name="sizeHint" stdset="0">
      <size>
       <width>8</width>
@@ -44,15 +27,8 @@
     </property>
    </spacer>
   </item>
-   <item row="9" column="0" colspan="3">
+   <item row="13" column="0">
-    <widget class="QCheckBox" name="versionCheckBox">
+    <spacer name="horizontalSpacer_3">
-     <property name="text">
-      <string>Only accept MAVs with same protocol version</string>
-     </property>
-    </widget>
-   </item>
-   <item row="10" column="0">
-    <spacer name="versionSpacer">
     <property name="orientation">
      <enum>Qt::Horizontal</enum>
     </property>
@@ -64,72 +40,28 @@
     </property>
    </spacer>
   </item>
-   <item row="10" column="1" colspan="2">
+   <item row="11" column="2">
-    <widget class="QLabel" name="versionLabel">
+    <widget class="QSpinBox" name="paramRewriteSpinBox">
-     <property name="text">
-      <string>MAVLINK_VERSION: </string>
-     </property>
-    </widget>
-   </item>
-   <item row="8" column="1">
-    <widget class="QLabel" name="logFileLabel">
-     <property name="text">
-      <string>Logfile name</string>
-     </property>
-    </widget>
-   </item>
-   <item row="8" column="2">
-    <widget class="QPushButton" name="logFileButton">
-     <property name="text">
-      <string>Select..</string>
-     </property>
-    </widget>
-   </item>
-   <item row="0" column="2">
-    <widget class="QSpinBox" name="systemIdSpinBox">
     <property name="toolTip">
-      <string>Set the groundstation number</string>
+      <string>Time in milliseconds after which a not acknowledged write request is sent again.</string>
     </property>
     <property name="statusTip">
-      <string>Set the groundstation number</string>
+      <string>Time in milliseconds after which a not acknowledged write request is sent again.</string>
+     </property>
+     <property name="suffix">
+      <string> ms</string>
     </property>
     <property name="minimum">
-      <number>1</number>
+      <number>50</number>
     </property>
     <property name="maximum">
-      <number>255</number>
+      <number>60000</number>
-     </property>
-    </widget>
-   </item>
-   <item row="0" column="0" colspan="2">
-    <widget class="QLabel" name="systemIdLabel">
-     <property name="toolTip">
-      <string>The system ID is the number the MAV associates with this computer</string>
-     </property>
-     <property name="statusTip">
-      <string>The system ID is the number the MAV associates with this computer</string>
     </property>
-     <property name="text">
+     <property name="singleStep">
-      <string>Groundstation MAVLink System ID</string>
+      <number>50</number>
     </property>
    </widget>
   </item>
-   <item row="5" column="0">
-    <spacer name="multiplexingFilterSpacer">
-     <property name="orientation">
-      <enum>Qt::Horizontal</enum>
-     </property>
-     <property name="sizeType">
-      <enum>QSizePolicy::MinimumExpanding</enum>
-     </property>
-     <property name="sizeHint" stdset="0">
-      <size>
-       <width>8</width>
-       <height>0</height>
-      </size>
-     </property>
-    </spacer>
-   </item>
   <item row="5" column="1" colspan="2">
    <widget class="QLineEdit" name="multiplexingFilterLineEdit">
     <property name="text">
@@ -137,28 +69,23 @@
     </property>
    </widget>
   </item>
-   <item row="4" column="0" colspan="3">
+   <item row="13" column="2">
-    <widget class="QCheckBox" name="multiplexingFilterCheckBox">
+    <widget class="QSpinBox" name="actionRetransmissionSpinBox">
-     <property name="text">
+     <property name="suffix">
-      <string>Filter multiplexed packets: Only forward selected IDs</string>
+      <string> ms</string>
     </property>
-    </widget>
+     <property name="minimum">
-   </item>
+      <number>20</number>
-   <item row="3" column="0" colspan="3">
-    <widget class="QCheckBox" name="multiplexingCheckBox">
-     <property name="text">
-      <string>Enable Multiplexing: Forward packets to all other links</string>
     </property>
-    </widget>
+     <property name="maximum">
-   </item>
+      <number>1000</number>
-   <item row="11" column="0" colspan="3">
+     </property>
-    <widget class="QCheckBox" name="paramGuardCheckBox">
+     <property name="singleStep">
-     <property name="text">
+      <number>10</number>
-      <string>Enable retransmission of parameter read/write requests</string>
     </property>
    </widget>
   </item>
-   <item row="12" column="0">
+   <item row="10" column="0">
    <spacer name="horizontalSpacer">
     <property name="orientation">
      <enum>Qt::Horizontal</enum>
@@ -171,34 +98,7 @@
     </property>
    </spacer>
   </item>
-   <item row="13" column="0">
+   <item row="10" column="2">
-    <spacer name="horizontalSpacer_2">
-     <property name="orientation">
-      <enum>Qt::Horizontal</enum>
-     </property>
-     <property name="sizeHint" stdset="0">
-      <size>
-       <width>8</width>
-       <height>0</height>
-      </size>
-     </property>
-    </spacer>
-   </item>
-   <item row="12" column="1">
-    <widget class="QLabel" name="paramRetransmissionLabel">
-     <property name="text">
-      <string>Read request retransmission timeout</string>
-     </property>
-    </widget>
-   </item>
-   <item row="13" column="1">
-    <widget class="QLabel" name="paramRewriteLabel">
-     <property name="text">
-      <string>Write request retransmission timeout</string>
-     </property>
-    </widget>
-   </item>
-   <item row="12" column="2">
    <widget class="QSpinBox" name="paramRetransmissionSpinBox">
     <property name="toolTip">
      <string>Time in milliseconds after which a not acknowledged read request is sent again.</string>
@@ -223,37 +123,41 @@
     </property>
    </widget>
   </item>
-   <item row="13" column="2">
+   <item row="14" column="0" colspan="3">
-    <widget class="QSpinBox" name="paramRewriteSpinBox">
+    <widget class="Line" name="line">
-     <property name="toolTip">
+     <property name="minimumSize">
-      <string>Time in milliseconds after which a not acknowledged write request is sent again.</string>
+      <size>
-     </property>
+       <width>0</width>
-     <property name="statusTip">
+       <height>0</height>
-      <string>Time in milliseconds after which a not acknowledged write request is sent again.</string>
+      </size>
-     </property>
-     <property name="suffix">
-      <string> ms</string>
-     </property>
-     <property name="minimum">
-      <number>50</number>
     </property>
-     <property name="maximum">
+     <property name="midLineWidth">
-      <number>60000</number>
+      <number>0</number>
     </property>
-     <property name="singleStep">
+     <property name="orientation">
-      <number>50</number>
+      <enum>Qt::Horizontal</enum>
     </property>
    </widget>
   </item>
-   <item row="14" column="0" colspan="3">
+   <item row="17" column="1" colspan="2">
-    <widget class="QCheckBox" name="actionGuardCheckBox">
+    <widget class="QComboBox" name="droneOSComboBox">
-     <property name="text">
+     <property name="editable">
-      <string>Enable retransmission of actions / commands</string>
+      <bool>true</bool>
     </property>
+     <item>
+      <property name="text">
+       <string>mavlink.droneos.com:14555</string>
+      </property>
+     </item>
+     <item>
+      <property name="text">
+       <string>localhost:14555</string>
+      </property>
+     </item>
    </widget>
   </item>
-   <item row="15" column="0">
+   <item row="11" column="0">
-    <spacer name="horizontalSpacer_3">
+    <spacer name="horizontalSpacer_2">
     <property name="orientation">
      <enum>Qt::Horizontal</enum>
     </property>
@@ -265,57 +169,106 @@
     </property>
    </spacer>
   </item>
-   <item row="15" column="1">
+   <item row="11" column="1">
-    <widget class="QLabel" name="actionRetransmissionLabel">
+    <widget class="QLabel" name="paramRewriteLabel">
     <property name="text">
-      <string>Action request retransmission timeout</string>
+      <string>Write request retransmission timeout</string>
     </property>
    </widget>
   </item>
-   <item row="15" column="2">
+   <item row="10" column="1">
-    <widget class="QSpinBox" name="actionRetransmissionSpinBox">
+    <widget class="QLabel" name="paramRetransmissionLabel">
-     <property name="suffix">
+     <property name="text">
-      <string> ms</string>
+      <string>Read request retransmission timeout</string>
     </property>
-     <property name="minimum">
+    </widget>
-      <number>20</number>
+   </item>
+   <item row="1" column="0" colspan="3">
+    <widget class="QCheckBox" name="heartbeatCheckBox">
+     <property name="text">
+      <string>Emit heartbeat</string>
     </property>
-     <property name="maximum">
+    </widget>
-      <number>1000</number>
+   </item>
+   <item row="3" column="0" colspan="3">
+    <widget class="QCheckBox" name="multiplexingCheckBox">
+     <property name="text">
+      <string>Enable Multiplexing: Forward packets to all other links</string>
     </property>
-     <property name="singleStep">
+    </widget>
-      <number>10</number>
+   </item>
+   <item row="13" column="1">
+    <widget class="QLabel" name="actionRetransmissionLabel">
+     <property name="text">
+      <string>Action request retransmission timeout</string>
     </property>
    </widget>
   </item>
-   <item row="16" column="0" colspan="3">
+   <item row="8" column="0">
-    <widget class="Line" name="line">
+    <spacer name="versionSpacer">
-     <property name="minimumSize">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+     <property name="sizeHint" stdset="0">
      <size>
-       <width>0</width>
+       <width>8</width>
       <height>0</height>
      </size>
     </property>
-     <property name="midLineWidth">
+    </spacer>
-      <number>0</number>
+   </item>
+   <item row="0" column="2">
+    <widget class="QSpinBox" name="systemIdSpinBox">
+     <property name="toolTip">
+      <string>Set the groundstation number</string>
     </property>
-     <property name="orientation">
+     <property name="statusTip">
-      <enum>Qt::Horizontal</enum>
+      <string>Set the groundstation number</string>
+     </property>
+     <property name="minimum">
+      <number>1</number>
+     </property>
+     <property name="maximum">
+      <number>255</number>
     </property>
    </widget>
   </item>
-   <item row="17" column="0" colspan="3">
+   <item row="15" column="0" colspan="3">
    <widget class="QCheckBox" name="droneOSCheckBox">
     <property name="text">
      <string>Forward MAVLink packets of all links to http://droneos.com</string>
     </property>
    </widget>
   </item>
-   <item row="18" column="0">
+   <item row="12" column="0" colspan="3">
-    <spacer name="horizontalSpacer_4">
+    <widget class="QCheckBox" name="actionGuardCheckBox">
+     <property name="text">
+      <string>Enable retransmission of actions / commands</string>
+     </property>
+    </widget>
+   </item>
+   <item row="4" column="0" colspan="3">
+    <widget class="QCheckBox" name="multiplexingFilterCheckBox">
+     <property name="text">
+      <string>Filter multiplexed packets: Only forward selected IDs</string>
+     </property>
+    </widget>
+   </item>
+   <item row="7" column="0" colspan="3">
+    <widget class="QCheckBox" name="versionCheckBox">
+     <property name="text">
+      <string>Only accept MAVs with same protocol version</string>
+     </property>
+    </widget>
+   </item>
+   <item row="5" column="0">
+    <spacer name="multiplexingFilterSpacer">
     <property name="orientation">
      <enum>Qt::Horizontal</enum>
     </property>
+     <property name="sizeType">
+      <enum>QSizePolicy::MinimumExpanding</enum>
+     </property>
     <property name="sizeHint" stdset="0">
      <size>
       <width>8</width>
@@ -324,7 +277,7 @@
     </property>
    </spacer>
   </item>
-   <item row="18" column="1" colspan="2">
+   <item row="16" column="1" colspan="2">
    <widget class="QLineEdit" name="droneOSLineEdit">
     <property name="text">
      <string>Enter your DroneOS API Token/Key</string>
@@ -334,21 +287,31 @@
     </property>
    </widget>
   </item>
-   <item row="19" column="1" colspan="2">
+   <item row="9" column="0" colspan="3">
-    <widget class="QComboBox" name="droneOSComboBox">
+    <widget class="QCheckBox" name="paramGuardCheckBox">
-     <property name="editable">
+     <property name="text">
-      <bool>true</bool>
+      <string>Enable retransmission of parameter read/write requests</string>
+     </property>
+    </widget>
+   </item>
+   <item row="8" column="1" colspan="2">
+    <widget class="QLabel" name="versionLabel">
+     <property name="text">
+      <string>MAVLINK_VERSION: </string>
+     </property>
+    </widget>
+   </item>
+   <item row="0" column="0" colspan="2">
+    <widget class="QLabel" name="systemIdLabel">
+     <property name="toolTip">
+      <string>The system ID is the number the MAV associates with this computer</string>
+     </property>
+     <property name="statusTip">
+      <string>The system ID is the number the MAV associates with this computer</string>
+     </property>
+     <property name="text">
+      <string>Groundstation MAVLink System ID</string>
     </property>
-     <item>
-      <property name="text">
-       <string>mavlink.droneos.com:14555</string>
-      </property>
-     </item>
-     <item>
-      <property name="text">
-       <string>localhost:14555</string>
-      </property>
-     </item>
    </widget>
   </item>
  </layout>

--- a/src/ui/MainWindow.cc
+++ b/src/ui/MainWindow.cc
@@ -70,6 +70,7 @@ This file is part of the QGROUNDCONTROL project
 #include "menuactionhelper.h"
 #include "QGCUASFileViewMulti.h"
 #include <QDesktopWidget>
+#include "QGCCore.h"
 #ifdef QGC_OSG_ENABLED
 #include "Q3DWidgetFactory.h"
@@ -80,41 +81,38 @@ This file is part of the QGROUNDCONTROL project
 #include "LogCompressor.h"
+static MainWindow* _instance = NULL;   ///< @brief MainWindow singleton
 // Set up some constants
 const QString MainWindow::defaultDarkStyle = ":files/styles/style-dark.css";
 const QString MainWindow::defaultLightStyle = ":files/styles/style-light.css";
-MainWindow* MainWindow::instance_mode(QSplashScreen* screen, enum MainWindow::CUSTOM_MODE mode)
+MainWindow* MainWindow::_create(QSplashScreen* splashScreen, enum MainWindow::CUSTOM_MODE mode)
 {
-    static MainWindow* _instance = 0;
+    Q_ASSERT(_instance == NULL);
-    if (_instance == 0)
+    Q_ASSERT(splashScreen);
-    {
-        _instance = new MainWindow();
+    new MainWindow(splashScreen, mode);
-        _instance->setCustomMode(mode);
-        if (screen)
+    // _instance is set in constructor
-        {
+    Q_ASSERT(_instance);
-            connect(_instance, SIGNAL(initStatusChanged(QString,int,QColor)),
-                    screen, SLOT(showMessage(QString,int,QColor)));
-        }
-        _instance->init();
-    }
    return _instance;
 }
-MainWindow* MainWindow::instance(QSplashScreen* screen)
+MainWindow* MainWindow::instance(void)
 {
-    return instance_mode(screen, CUSTOM_MODE_UNCHANGED);
+    // QGCAppication should have already called _create. Singleton is only created by call to _create
+    // not here.
+    Q_ASSERT(_instance);
+    return _instance;
 }
-/**
+/// @brief Private constructor for MainWindow. MainWindow singleton is only ever created
-* Create new mainwindow. The constructor instantiates all parts of the user
+///         by MainWindow::_create method. Hence no other code should have access to
-* interface. It does NOT show the mainwindow. To display it, call the show()
+///         constructor.
-* method.
+MainWindow::MainWindow(QSplashScreen* splashScreen, enum MainWindow::CUSTOM_MODE mode) :
-*
-* @see QMainWindow::show()
-**/
-MainWindow::MainWindow(QWidget *parent):
-    QMainWindow(parent),
    currentView(VIEW_FLIGHT),
    currentStyle(QGC_MAINWINDOW_STYLE_DARK),
    aboutToCloseFlag(false),
@@ -124,19 +122,25 @@ MainWindow::MainWindow(QWidget *parent):
    autoReconnect(false),
    simulationLink(NULL),
    lowPowerMode(false),
-    customMode(CUSTOM_MODE_NONE),
+    customMode(mode),
-    menuActionHelper(new MenuActionHelper())
+    menuActionHelper(new MenuActionHelper()),
+    _splashScreen(splashScreen)
 {
+    Q_ASSERT(splashScreen);
+    Q_ASSERT(_instance == NULL);
+    _instance = this;
+    connect(this, &MainWindow::initStatusChanged, splashScreen, &QSplashScreen::showMessage);
    this->setAttribute(Qt::WA_DeleteOnClose);
    connect(menuActionHelper, SIGNAL(needToShowDockWidget(QString,bool)),SLOT(showDockWidget(QString,bool)));
-    //TODO:  move protocol outside UI
-    connect(mavlink, SIGNAL(protocolStatusMessage(QString,QString)), this, SLOT(showCriticalMessage(QString,QString)), Qt::QueuedConnection);
+    connect(mavlink, &MAVLinkProtocol::protocolStatusMessage, this, &MainWindow::showCriticalMessage);
+    connect(mavlink, &MAVLinkProtocol::saveTempFlightDataLog, this, &MainWindow::_saveTempFlightDataLog);
    loadSettings();
-}
-void MainWindow::init()
-{
    emit initStatusChanged(tr("Loading style"), Qt::AlignLeft | Qt::AlignBottom, QColor(62, 93, 141));
    qApp->setStyle("plastique");
    loadStyle(currentStyle);
@@ -261,11 +265,15 @@ void MainWindow::init()
    // Connect link
    if (autoReconnect)
    {
+        LinkManager* linkMgr = LinkManager::instance();
+        Q_ASSERT(linkMgr);
        SerialLink* link = new SerialLink();
        // Add to registry
-        LinkManager::instance()->add(link);
+        linkMgr->add(link);
-        LinkManager::instance()->addProtocol(link, mavlink);
+        linkMgr->addProtocol(link, mavlink);
-        link->connect();
+        linkMgr->connectLink(link);
    }
    // Set low power mode
@@ -1122,24 +1130,16 @@ void MainWindow::showStatusMessage(const QString& status)
 void MainWindow::showCriticalMessage(const QString& title, const QString& message)
 {
-    QMessageBox msgBox(this);
+    _hideSplashScreen();
-    msgBox.setIcon(QMessageBox::Critical);
+    qDebug() << "Critical" << title << message;
-    msgBox.setText(title);
+    QMessageBox::critical(this, title, message);
-    msgBox.setInformativeText(message);
-    msgBox.setStandardButtons(QMessageBox::Ok);
-    msgBox.setDefaultButton(QMessageBox::Ok);
-    msgBox.exec();
 }
 void MainWindow::showInfoMessage(const QString& title, const QString& message)
 {
-    QMessageBox msgBox(this);
+    _hideSplashScreen();
-    msgBox.setIcon(QMessageBox::Information);
+    qDebug() << "Information" << title << message;
-    msgBox.setText(title);
+    QMessageBox::information(this, title, message);
-    msgBox.setInformativeText(message);
-    msgBox.setStandardButtons(QMessageBox::Ok);
-    msgBox.setDefaultButton(QMessageBox::Ok);
-    msgBox.exec();
 }
 /**
@@ -1276,52 +1276,37 @@ void MainWindow::connectCommonActions()
    connect(ui.actionSimulate, SIGNAL(triggered(bool)), this, SLOT(simulateLink(bool)));
 }
-void MainWindow::showHelp()
+void MainWindow::_openUrl(const QString& url, const QString& errorMessage)
 {
-    if(!QDesktopServices::openUrl(QUrl("http://qgroundcontrol.org/users/start")))
+    if(!QDesktopServices::openUrl(QUrl(url))) {
-    {
+        QMessageBox::critical(this,
-        QMessageBox msgBox;
+                              tr("Could not open information in browser"),
-        msgBox.setIcon(QMessageBox::Critical);
+                              errorMessage);
-        msgBox.setText("Could not open help in browser");
-        msgBox.setInformativeText("To get to the online help, please open http://qgroundcontrol.org/user_guide in a browser.");
-        msgBox.setStandardButtons(QMessageBox::Ok);
-        msgBox.setDefaultButton(QMessageBox::Ok);
-        msgBox.exec();
    }
 }
+void MainWindow::showHelp()
+{
+    _openUrl("http://qgroundcontrol.org/users/start",
+             tr("To get to the online help, please open http://qgroundcontrol.org/user_guide in a browser."));
+}
 void MainWindow::showCredits()
 {
-    if(!QDesktopServices::openUrl(QUrl("http://qgroundcontrol.org/credits")))
+    _openUrl("http://qgroundcontrol.org/credits",
-    {
+             tr("To get to the credits, please open http://qgroundcontrol.org/credits in a browser."));
-        QMessageBox msgBox;
-        msgBox.setIcon(QMessageBox::Critical);
-        msgBox.setText("Could not open credits in browser");
-        msgBox.setInformativeText("To get to the online help, please open http://qgroundcontrol.org/credits in a browser.");
-        msgBox.setStandardButtons(QMessageBox::Ok);
-        msgBox.setDefaultButton(QMessageBox::Ok);
-        msgBox.exec();
-    }
 }
 void MainWindow::showRoadMap()
 {
-    if(!QDesktopServices::openUrl(QUrl("http://qgroundcontrol.org/dev/roadmap")))
+    _openUrl("http://qgroundcontrol.org/dev/roadmap",
-    {
+             tr("To get to the online help, please open http://qgroundcontrol.org/roadmap in a browser."));
-        QMessageBox msgBox;
-        msgBox.setIcon(QMessageBox::Critical);
-        msgBox.setText("Could not open roadmap in browser");
-        msgBox.setInformativeText("To get to the online help, please open http://qgroundcontrol.org/roadmap in a browser.");
-        msgBox.setStandardButtons(QMessageBox::Ok);
-        msgBox.setDefaultButton(QMessageBox::Ok);
-        msgBox.exec();
-    }
 }
 void MainWindow::showSettings()
 {
-    QGCSettingsWidget* settings = new QGCSettingsWidget(joystick, this);
+    SettingsDialog settings(joystick, this);
-    settings->show();
+    settings.exec();
 }
 LinkInterface* MainWindow::addLink()
@@ -1412,9 +1397,16 @@ void MainWindow::addLink(LinkInterface *link)
 }
 void MainWindow::simulateLink(bool simulate) {
-    if (!simulationLink)
+    if (simulate) {
-        simulationLink = new MAVLinkSimulationLink(":/demo-log.txt");
+        if (!simulationLink) {
-    simulationLink->connectLink(simulate);
+            simulationLink = new MAVLinkSimulationLink(":/demo-log.txt");
+            Q_CHECK_PTR(simulationLink);
+        }
+        LinkManager::instance()->connectLink(simulationLink);
+    } else {
+        Q_ASSERT(simulationLink);
+        LinkManager::instance()->disconnectLink(simulationLink);
+    }
 }
 void MainWindow::commsWidgetDestroyed(QObject *obj)
@@ -1700,6 +1692,9 @@ void MainWindow::handleMisconfiguration(UASInterface* uas)
            return;
        }
    }
+    _hideSplashScreen();
    // Ask user if he wants to handle this now
    QMessageBox msgBox(this);
    msgBox.setIcon(QMessageBox::Information);
@@ -1826,6 +1821,31 @@ bool MainWindow::dockWidgetTitleBarsEnabled() const
    return menuActionHelper->dockWidgetTitleBarsEnabled();
 }
+void MainWindow::_saveTempFlightDataLog(QString tempLogfile)
+{
+    if (qgcApp()->promptFlightDataSave()) {
+        _hideSplashScreen();
+        QString saveFilename = QFileDialog::getSaveFileName(this,
+                                                            tr("Select file to save Flight Data Log"),
+                                                            qgcApp()->mavlinkLogFilesLocation(),
+                                                            tr("Flight Data Log (*.mavlink)"));
+        if (!saveFilename.isEmpty()) {
+            QFile::copy(tempLogfile, saveFilename);
+        }
+    }
+    QFile::remove(tempLogfile);
+}
+/// @brief Hides the spash screen if it is currently being shown
+void MainWindow::_hideSplashScreen(void)
+{
+    if (_splashScreen) {
+        _splashScreen->hide();
+        _splashScreen = NULL;
+    }
+}
 #ifdef QGC_MOUSE_ENABLED_LINUX
 bool MainWindow::x11Event(XEvent *event)
 {

--- a/src/ui/MainWindow.h
+++ b/src/ui/MainWindow.h
@@ -100,31 +100,18 @@ public:
        CUSTOM_MODE_WIFI
    };
-    /**
+    /// @brief Returns the MainWindow singleton. Will not create the MainWindow if it has not already
-     * A static function for obtaining the sole instance of the MainWindow. The screen
+    ///         been created.
-     * argument is only important on the FIRST call to this function. The provided splash
+    static MainWindow* instance(void);
-     * screen is updated with some status messages that are emitted during init(). This
-     * function cannot be used within the MainWindow constructor!
+    /// @brief Creates the MainWindow singleton. Should only be called once by QGCApplication.
-     */
+    static MainWindow* _create(QSplashScreen* splashScreen, enum MainWindow::CUSTOM_MODE mode);
-    static MainWindow* instance(QSplashScreen* screen = 0);
-    static MainWindow* instance_mode(QSplashScreen* screen = 0, enum MainWindow::CUSTOM_MODE mode = MainWindow::CUSTOM_MODE_NONE);
+    /// @brief Called to indicate that splash screen is no longer being displayed.
+    void splashScreenFinished(void) { _splashScreen = NULL; }
-    /**
-     * Initializes the MainWindow. Some variables are initialized and the widget is hidden.
-     * Initialization of the MainWindow class really occurs in init(), which loads the UI
-     * and does everything important. The constructor is split in two like this so that
-     * the instance() is available for all classes.
-     */
-    MainWindow(QWidget *parent = NULL);
    ~MainWindow();
-    /**
-     * This function actually performs the non-trivial initialization of the MainWindow
-     * class. This is separate from the constructor because instance() won't work within
-     * code executed in the MainWindow constructor.
-     */
-    void init();
    enum QGC_MAINWINDOW_STYLE
    {
        QGC_MAINWINDOW_STYLE_DARK,
@@ -272,7 +259,7 @@ public slots:
    void configureWindowName();
    void commsWidgetDestroyed(QObject *obj);
 protected slots:
    void showDockWidget(const QString &name, bool show);
    /**
@@ -475,8 +462,18 @@ protected:
    QGCFlightGearLink* fgLink;
    QTimer windowNameUpdateTimer;
    CUSTOM_MODE customMode;
+private slots:
+    /// @brief Save the specified Flight Data Log
+    void _saveTempFlightDataLog(QString tempLogfile);
 private:
+    /// Constructor is private since all creation should be through MainWindow::instance.
+    MainWindow(QSplashScreen* splashScreen, enum MainWindow::CUSTOM_MODE mode);
+    void _hideSplashScreen(void);
+    void _openUrl(const QString& url, const QString& errorMessage);
    QList<QObject*> commsWidgetList;
    QMap<QString,QString> customWidgetNameToFilenameMap;
    MenuActionHelper *menuActionHelper;
@@ -489,6 +486,8 @@ private:
    QString getWindowStateKey();
    QString getWindowGeometryKey();
+    QSplashScreen* _splashScreen;   ///< Splash screen, NULL is splash screen not currently being shown
    friend class MenuActionHelper; //For VIEW_SECTIONS
 };

--- a/src/ui/QGCMAVLinkLogPlayer.cc
+++ b/src/ui/QGCMAVLinkLogPlayer.cc
@@ -8,6 +8,8 @@
 #include "QGCMAVLinkLogPlayer.h"
 #include "QGC.h"
 #include "ui_QGCMAVLinkLogPlayer.h"
+#include "QGCCore.h"
+#include "LinkManager.h"
 QGCMAVLinkLogPlayer::QGCMAVLinkLogPlayer(MAVLinkProtocol* mavlink, QWidget *parent) :
    QWidget(parent),
@@ -22,9 +24,10 @@ QGCMAVLinkLogPlayer::QGCMAVLinkLogPlayer(MAVLinkProtocol* mavlink, QWidget *pare
    binaryBaudRate(defaultBinaryBaudRate),
    isPlaying(false),
    currPacketCount(0),
-    lastLogDirectory(QStandardPaths::writableLocation(QStandardPaths::DesktopLocation)),
    ui(new Ui::QGCMAVLinkLogPlayer)
 {
+    Q_ASSERT(mavlink);
    ui->setupUi(this);
    ui->horizontalLayout->setAlignment(Qt::AlignTop);
@@ -32,14 +35,18 @@ QGCMAVLinkLogPlayer::QGCMAVLinkLogPlayer(MAVLinkProtocol* mavlink, QWidget *pare
    connect(this, SIGNAL(bytesReady(LinkInterface*,QByteArray)), mavlink, SLOT(receiveBytes(LinkInterface*,QByteArray)));
    // Setup timer
-    connect(&loopTimer, SIGNAL(timeout()), this, SLOT(logLoop()));
+    connect(&loopTimer, &QTimer::timeout, this, &QGCMAVLinkLogPlayer::logLoop);
    // Setup buttons
-    connect(ui->selectFileButton, SIGNAL(clicked()), this, SLOT(selectLogFile()));
+    connect(ui->selectFileButton, &QPushButton::clicked, this, &QGCMAVLinkLogPlayer::_selectLogFileForPlayback);
-    connect(ui->playButton, SIGNAL(clicked()), this, SLOT(playPauseToggle()));
+    connect(ui->playButton, &QPushButton::clicked, this, &QGCMAVLinkLogPlayer::playPauseToggle);
-    connect(ui->speedSlider, SIGNAL(valueChanged(int)), this, SLOT(setAccelerationFactorInt(int)));
+    connect(ui->speedSlider, &QSlider::valueChanged, this, &QGCMAVLinkLogPlayer::setAccelerationFactorInt);
-    connect(ui->positionSlider, SIGNAL(valueChanged(int)), this, SLOT(jumpToSliderVal(int)));
+    connect(ui->positionSlider, &QSlider::valueChanged, this, &QGCMAVLinkLogPlayer::jumpToSliderVal);
-    connect(ui->positionSlider, SIGNAL(sliderPressed()), this, SLOT(pause()));
+    connect(ui->positionSlider, &QSlider::sliderPressed, this, &QGCMAVLinkLogPlayer::pause);
+    // We use this to queue the signal over to mavlink. This way it will be behind any remaining
+    // bytesReady signals in the queue.
+    connect(this, &QGCMAVLinkLogPlayer::suspendLogForReplay, mavlink, &MAVLinkProtocol::suspendLogForReplay);
    setAccelerationFactorInt(49);
    ui->speedSlider->setValue(49);
@@ -53,29 +60,14 @@ QGCMAVLinkLogPlayer::QGCMAVLinkLogPlayer(MAVLinkProtocol* mavlink, QWidget *pare
    ui->logStatsLabel->setEnabled(false);
    // Monitor for when the end of the log file is reached. This is done using signals because the main work is in a timer.
-    connect(this, SIGNAL(logFileEndReached()), &loopTimer, SLOT(stop()));
+    connect(this,  &QGCMAVLinkLogPlayer::logFileEndReached, &loopTimer, &QTimer::stop);
-    loadSettings();
 }
 QGCMAVLinkLogPlayer::~QGCMAVLinkLogPlayer()
 {
-    storeSettings();
    delete ui;
 }
-void QGCMAVLinkLogPlayer::playPause(bool enabled)
-{
-    if (enabled)
-    {
-        play();
-    }
-    else
-    {
-        pause();
-    }
-}
 void QGCMAVLinkLogPlayer::playPauseToggle()
 {
    if (isPlaying)
@@ -90,55 +82,49 @@ void QGCMAVLinkLogPlayer::playPauseToggle()
 void QGCMAVLinkLogPlayer::play()
 {
-    if (logFile.isOpen())
+    Q_ASSERT(logFile.isOpen());
+    LinkManager::instance()->setConnectionsSuspended(tr("Connect not allowed during Flight Data replay."));
+    emit suspendLogForReplay(true);
+    // Disable the log file selector button
+    ui->selectFileButton->setEnabled(false);
+    // Make sure we aren't at the end of the file, if we are, reset to the beginning and play from there.
+    if (logFile.atEnd())
    {
-        // Disable the log file selector button
+        reset();
-        ui->selectFileButton->setEnabled(false);
+    }
-        // Make sure we aren't at the end of the file, if we are, reset to the beginning and play from there.
-        if (logFile.atEnd())
-        {
-            reset();
-        }
-        // Always correct the current start time such that the next message will play immediately at playback.
+    // Always correct the current start time such that the next message will play immediately at playback.
-        // We do this by subtracting the current file playback offset  from now()
+    // We do this by subtracting the current file playback offset  from now()
-        playbackStartTime = (quint64)QDateTime::currentMSecsSinceEpoch() - (logCurrentTime - logStartTime) / 1000;
+    playbackStartTime = (quint64)QDateTime::currentMSecsSinceEpoch() - (logCurrentTime - logStartTime) / 1000;
-        // Start timer
+    // Start timer
-        if (mavlinkLogFormat)
+    if (mavlinkLogFormat)
-        {
+    {
-            loopTimer.start(1);
+        loopTimer.start(1);
-        }
-        else
-        {
-            // Read len bytes at a time
-            int len = 100;
-            // Calculate the number of times to read 100 bytes per second
-            // to guarantee the baud rate, then divide 1000 by the number of read
-            // operations to obtain the interval in milliseconds
-            int interval = 1000 / ((binaryBaudRate / 10) / len);
-            loopTimer.start(interval / accelerationFactor);
-        }
-        isPlaying = true;
-        ui->playButton->setChecked(true);
-        ui->playButton->setIcon(QIcon(":files/images/actions/media-playback-pause.svg"));
    }
    else
    {
-        ui->playButton->setChecked(false);
+        // Read len bytes at a time
-        QMessageBox msgBox;
+        int len = 100;
-        msgBox.setIcon(QMessageBox::Information);
+        // Calculate the number of times to read 100 bytes per second
-        msgBox.setText(tr("No logfile selected"));
+        // to guarantee the baud rate, then divide 1000 by the number of read
-        msgBox.setInformativeText(tr("Please select first a MAVLink log file before playing it."));
+        // operations to obtain the interval in milliseconds
-        msgBox.setStandardButtons(QMessageBox::Ok);
+        int interval = 1000 / ((binaryBaudRate / 10) / len);
-        msgBox.setDefaultButton(QMessageBox::Ok);
+        loopTimer.start(interval / accelerationFactor);
-        msgBox.exec();
    }
+    isPlaying = true;
+    ui->playButton->setChecked(true);
+    ui->playButton->setIcon(QIcon(":files/images/actions/media-playback-pause.svg"));
 }
 void QGCMAVLinkLogPlayer::pause()
 {
+    LinkManager::instance()->setConnectionsAllowed();
+    emit suspendLogForReplay(false);
    loopTimer.stop();
    isPlaying = false;
    ui->playButton->setIcon(QIcon(":files/images/actions/media-playback-start.svg"));
@@ -258,51 +244,33 @@ void QGCMAVLinkLogPlayer::updatePositionSliderUi(float percent)
    ui->positionSlider->blockSignals(false);
 }
-void QGCMAVLinkLogPlayer::loadSettings()
+/// @brief Displays a file dialog to allow the user to select a log file to play back.
+void QGCMAVLinkLogPlayer::_selectLogFileForPlayback(void)
 {
-    QSettings settings;
+    // Disallow replay when any links are connected
-    settings.beginGroup("QGC_MAVLINKLOGPLAYER");
-    lastLogDirectory = settings.value("LAST_LOG_DIRECTORY", lastLogDirectory).toString();
+    bool foundConnection = false;
-    settings.endGroup();
+    LinkManager* linkMgr = LinkManager::instance();
-}
+    QList<LinkInterface*> links = linkMgr->getLinks();
+    foreach(LinkInterface* link, links) {
-void QGCMAVLinkLogPlayer::storeSettings()
+        if (link->isConnected()) {
-{
+            foundConnection = true;
-    QSettings settings;
+            break;
-    settings.beginGroup("QGC_MAVLINKLOGPLAYER");
+        }
-    settings.setValue("LAST_LOG_DIRECTORY", lastLogDirectory);
-    settings.endGroup();
-    settings.sync();
-}
-/**
- * @brief Select a log file
- * @param startDirectory Directory where the file dialog will be opened
- * @return filename of the logFile
- */
-bool QGCMAVLinkLogPlayer::selectLogFile()
-{
-    // Prompt the user for a new file using the last directory they searched.
-    return selectLogFile(lastLogDirectory);
-}
-/**
- * @brief Select a log file
- * @param startDirectory Directory where the file dialog will be opened
- * @return filename of the logFile
- */
-bool QGCMAVLinkLogPlayer::selectLogFile(const QString startDirectory)
-{
-    QString fileName = QFileDialog::getOpenFileName(this, tr("Specify MAVLink log file name to replay"), startDirectory, tr("MAVLink or Binary Logfile (*.mavlink *.bin *.log)"));
-    if (fileName == "")
-    {
-        return false;
    }
-    else
-    {
+    if (foundConnection) {
-        lastLogDirectory = fileName;
+        MainWindow::instance()->showInfoMessage(tr("Log Replay"), tr("You must close all connections prior to replaying a log."));
-        return loadLogFile(fileName);
+        return;
+    }
+    QString logFile = QFileDialog::getOpenFileName(this,
+                                                    tr("Specify MAVLink log file name to replay"),
+                                                    qgcApp()->mavlinkLogFilesLocation(),
+                                                    tr("MAVLink or Binary Logfile (*.mavlink *.bin *.log)"));
+    if (!logFile.isEmpty()) {
+        loadLogFile(logFile);
    }
 }
@@ -341,157 +309,125 @@ void QGCMAVLinkLogPlayer::setAccelerationFactorInt(int factor)
 bool QGCMAVLinkLogPlayer::loadLogFile(const QString& file)
 {
-    // Enable controls
-    ui->playButton->setEnabled(true);
-    ui->speedSlider->setEnabled(true);
-    ui->positionSlider->setEnabled(true);
-    ui->speedLabel->setEnabled(true);
-    ui->logFileNameLabel->setEnabled(true);
-    ui->logStatsLabel->setEnabled(true);
-    // Disable logging while replaying a log file.
-    if (mavlink->loggingEnabled())
-    {
-        mavlink->enableLogging(false);
-        MainWindow::instance()->showInfoMessage(tr("MAVLink Logging Stopped during Replay"), tr("MAVLink logging has been stopped during the log replay. To re-enable logging, use the link properties in the communication menu."));
-    }
    // Make sure to stop the logging process and reset everything.
    reset();
+    logFile.close();
-    // And that the old file is closed nicely.
-    if (logFile.isOpen())
-    {
-        logFile.close();
-    }
    // Now load the new file.
    logFile.setFileName(file);
-    if (!logFile.open(QFile::ReadOnly))
+    if (!logFile.open(QFile::ReadOnly)) {
-    {
+        MainWindow::instance()->showCriticalMessage(tr("The selected file is unreadable"), tr("Please make sure that the file %1 is readable or select a different file").arg(file));
-        MainWindow::instance()->showCriticalMessage(tr("The selected logfile is unreadable"), tr("Please make sure that the file %1 is readable or select a different file").arg(file));
+        _playbackError();
-        logFile.setFileName("");
        return false;
    }
-    else
-    {
+    QFileInfo logFileInfo(file);
-        QFileInfo logFileInfo(file);
+    ui->logFileNameLabel->setText(tr("File: %1").arg(logFileInfo.fileName()));
-        logFile.reset();
-        ui->logFileNameLabel->setText(tr("Logfile: %1").arg(logFileInfo.fileName()));
-        // If there's an existing MAVLinkSimulationLink() being used for an old file,
-        // we replace it.
-        if (logLink)
-        {
-            logLink->disconnect();
-            LinkManager::instance()->removeLink(logLink);
-            delete logLink;
-        }
-        logLink = new MAVLinkSimulationLink("");
+    // If there's an existing MAVLinkSimulationLink() being used for an old file,
+    // we replace it.
+    if (logLink)
+    {
+        LinkManager::instance()->disconnectLink(logLink);
+        LinkManager::instance()->removeLink(logLink);
+        logLink->deleteLater();
+    }
+    logLink = new MAVLinkSimulationLink("");
-        // Select if binary or MAVLink log format is used
+    // Select if binary or MAVLink log format is used
-        mavlinkLogFormat = file.endsWith(".mavlink");
+    mavlinkLogFormat = file.endsWith(".mavlink");
-        if (mavlinkLogFormat)
-        {
-            // Get the first timestamp from the logfile
-            // This should be a big-endian uint64.
-            QByteArray timestamp = logFile.read(timeLen);
-            quint64 starttime = parseTimestamp(timestamp);
-            // Now find the last timestamp by scanning for the last MAVLink packet and
-            // find the timestamp before it. To do this we start searchin a little before
-            // the end of the file, specifically the maximum MAVLink packet size + the
-            // timestamp size. This guarantees that we will hit a MAVLink packet before
-            // the end of the file. Unfortunately, it basically guarantees that we will
-            // hit more than one. This is why we have to search for a bit.
-            qint64 fileLoc = logFile.size() - MAVLINK_MAX_PACKET_LEN - timeLen;
-            logFile.seek(fileLoc);
-            quint64 endtime = starttime; // Set a sane default for the endtime
-            mavlink_message_t msg;
-            quint64 newTimestamp;
-            while ((newTimestamp = findNextMavlinkMessage(&msg)) > endtime) {
-                endtime = newTimestamp;
-            }
-            if (endtime == starttime) {
+    if (mavlinkLogFormat)
-                MainWindow::instance()->showCriticalMessage(tr("The selected logfile cannot be processed"), tr("No valid timestamps were found at the end of the logfile.").arg(file));
+    {
-                logFile.setFileName("");
+        // Get the first timestamp from the logfile
-                ui->logFileNameLabel->setText(tr("No logfile selected"));
+        // This should be a big-endian uint64.
-                return false;
+        QByteArray timestamp = logFile.read(timeLen);
-            }
+        quint64 starttime = parseTimestamp(timestamp);
+        // Now find the last timestamp by scanning for the last MAVLink packet and
+        // find the timestamp before it. To do this we start searchin a little before
+        // the end of the file, specifically the maximum MAVLink packet size + the
+        // timestamp size. This guarantees that we will hit a MAVLink packet before
+        // the end of the file. Unfortunately, it basically guarantees that we will
+        // hit more than one. This is why we have to search for a bit.
+        qint64 fileLoc = logFile.size() - MAVLINK_MAX_PACKET_LEN - timeLen;
+        logFile.seek(fileLoc);
+        quint64 endtime = starttime; // Set a sane default for the endtime
+        mavlink_message_t msg;
+        quint64 newTimestamp;
+        while ((newTimestamp = findNextMavlinkMessage(&msg)) > endtime) {
+            endtime = newTimestamp;
+        }
-            // Remember the start and end time so we can move around this logfile with the slider.
+        if (endtime == starttime) {
-            logEndTime = endtime;
+            MainWindow::instance()->showCriticalMessage(tr("The selected file is corrupt"), tr("No valid timestamps were found at the end of the file.").arg(file));
-            logStartTime = starttime;
+            _playbackError();
-            logCurrentTime = logStartTime;
+            return false;
+        }
-            // Reset our log file so when we go to read it for the first time, we start at the beginning.
+        // Remember the start and end time so we can move around this logfile with the slider.
-            logFile.reset();
+        logEndTime = endtime;
+        logStartTime = starttime;
+        logCurrentTime = logStartTime;
-            // Calculate the runtime in hours:minutes:seconds
+        // Reset our log file so when we go to read it for the first time, we start at the beginning.
-            // WARNING: Order matters in this computation
+        logFile.reset();
-            quint32 seconds = (endtime - starttime)/1000000;
-            quint32 minutes = seconds / 60;
-            quint32 hours = minutes / 60;
-            seconds -= 60*minutes;
-            minutes -= 60*hours;
-            // And show the user the details we found about this file.
+        // Calculate the runtime in hours:minutes:seconds
-            QString timelabel = tr("%1h:%2m:%3s").arg(hours, 2).arg(minutes, 2).arg(seconds, 2);
+        // WARNING: Order matters in this computation
-            currPacketCount = logFileInfo.size()/(32 + MAVLINK_NUM_NON_PAYLOAD_BYTES + sizeof(quint64)); // Count packets by assuming an average payload size of 32 bytes
+        quint32 seconds = (endtime - starttime)/1000000;
-            ui->logStatsLabel->setText(tr("%2 MB, ~%3 packets, %4").arg(logFileInfo.size()/1000000.0f, 0, 'f', 2).arg(currPacketCount).arg(timelabel));
+        quint32 minutes = seconds / 60;
-        }
+        quint32 hours = minutes / 60;
-        else
+        seconds -= 60*minutes;
+        minutes -= 60*hours;
+        // And show the user the details we found about this file.
+        QString timelabel = tr("%1h:%2m:%3s").arg(hours, 2).arg(minutes, 2).arg(seconds, 2);
+        currPacketCount = logFileInfo.size()/(32 + MAVLINK_NUM_NON_PAYLOAD_BYTES + sizeof(quint64)); // Count packets by assuming an average payload size of 32 bytes
+        ui->logStatsLabel->setText(tr("%2 MB, ~%3 packets, %4").arg(logFileInfo.size()/1000000.0f, 0, 'f', 2).arg(currPacketCount).arg(timelabel));
+    }
+    else
+    {
+        // Load in binary mode. In this mode, files should be have a filename postfix
+        // of the baud rate they were recorded at, like `test_run_115200.bin`. Then on
+        // playback, the datarate is equal to set to this value.
+        // Set baud rate if any present. Otherwise we default to 57600.
+        QStringList parts = logFileInfo.baseName().split("_");
+        binaryBaudRate = defaultBinaryBaudRate;
+        if (parts.count() > 1)
        {
-            // Load in binary mode. In this mode, files should be have a filename postfix
+            bool ok;
-            // of the baud rate they were recorded at, like `test_run_115200.bin`. Then on
+            int rate = parts.last().toInt(&ok);
-            // playback, the datarate is equal to set to this value.
+            // 9600 baud to 100 MBit
+            if (ok && (rate > 9600 && rate < 100000000))
-            // Set baud rate if any present. Otherwise we default to 57600.
-            QStringList parts = logFileInfo.baseName().split("_");
-            binaryBaudRate = defaultBinaryBaudRate;
-            if (parts.count() > 1)
            {
-                bool ok;
+                // Accept this as valid baudrate
-                int rate = parts.last().toInt(&ok);
+                binaryBaudRate = rate;
-                // 9600 baud to 100 MBit
-                if (ok && (rate > 9600 && rate < 100000000))
-                {
-                    // Accept this as valid baudrate
-                    binaryBaudRate = rate;
-                }
            }
-            int seconds = logFileInfo.size() / (binaryBaudRate / 10);
-            int minutes = seconds / 60;
-            int hours = minutes / 60;
-            seconds -= 60*minutes;
-            minutes -= 60*hours;
-            QString timelabel = tr("%1h:%2m:%3s").arg(hours, 2).arg(minutes, 2).arg(seconds, 2);
-            ui->logStatsLabel->setText(tr("%2 MB, %4 at %5 KB/s").arg(logFileInfo.size()/1000000.0f, 0, 'f', 2).arg(timelabel).arg(binaryBaudRate/10.0f/1024.0f, 0, 'f', 2));
        }
-        // Check if a serial link is connected
+        int seconds = logFileInfo.size() / (binaryBaudRate / 10);
+        int minutes = seconds / 60;
-        bool linkWarning = false;
+        int hours = minutes / 60;
-        foreach (LinkInterface* link, LinkManager::instance()->getLinks())
+        seconds -= 60*minutes;
-        {
+        minutes -= 60*hours;
-            SerialLink* s = dynamic_cast<SerialLink*>(link);
-            if (s && s->isConnected())
-                linkWarning = true;
-        }
-        if (linkWarning)
+        QString timelabel = tr("%1h:%2m:%3s").arg(hours, 2).arg(minutes, 2).arg(seconds, 2);
-            MainWindow::instance()->showInfoMessage(tr("Active MAVLink links found"), tr("Currently other links are connected. It is recommended to disconnect any active link before replaying a log."));
+        ui->logStatsLabel->setText(tr("%2 MB, %4 at %5 KB/s").arg(logFileInfo.size()/1000000.0f, 0, 'f', 2).arg(timelabel).arg(binaryBaudRate/10.0f/1024.0f, 0, 'f', 2));
+    }
-        play();
+    // Enable controls
+    ui->playButton->setEnabled(true);
+    ui->speedSlider->setEnabled(true);
+    ui->positionSlider->setEnabled(true);
+    ui->speedLabel->setEnabled(true);
+    ui->logFileNameLabel->setEnabled(true);
+    ui->logStatsLabel->setEnabled(true);
+    play();
-        return true;
+    return true;
-    }
 }
 quint64 QGCMAVLinkLogPlayer::parseTimestamp(const QByteArray &data)
@@ -593,17 +529,8 @@ void QGCMAVLinkLogPlayer::logLoop()
            emit bytesReady(logLink, message);
            // If we've reached the end of the of the file, make sure we handle that well
-            if (logFile.atEnd())
+            if (logFile.atEnd()) {
-            {
+                _finishPlayback();
-                // For some reason calling pause() here doesn't work, so we update the UI manually here.
-                isPlaying = false;
-                ui->playButton->setIcon(QIcon(":files/images/actions/media-playback-start.svg"));
-                ui->playButton->setChecked(false);
-                ui->selectFileButton->setEnabled(true);
-                // Note that we explicitly set the slider to 100%, as it may not hit that by itself depending on log file size.
-                updatePositionSliderUi(100.0f);
-                emit logFileEndReached();
                return;
            }
@@ -633,12 +560,7 @@ void QGCMAVLinkLogPlayer::logLoop()
        // Check if reached end of file before reading next timestamp
        if (chunk.length() < len || logFile.atEnd())
        {
-            // Reached end of file
+            _finishPlayback();
-            reset();
-            QString status = tr("Reached end of binary log file.");
-            ui->logStatsLabel->setText(status);
-            MainWindow::instance()->showStatusMessage(status);
            return;
        }
    }
@@ -707,3 +629,40 @@ void QGCMAVLinkLogPlayer::paintEvent(QPaintEvent *)
    QPainter p(this);
    style()->drawPrimitive(QStyle::PE_Widget, &opt, &p, this);
 }
+/// @brief Called when playback is complete
+void QGCMAVLinkLogPlayer::_finishPlayback(void)
+{
+    pause();
+    QString status = tr("Flight Data replay complete");
+    ui->logStatsLabel->setText(status);
+    MainWindow::instance()->showStatusMessage(status);
+    // Note that we explicitly set the slider to 100%, as it may not hit that by itself depending on log file size.
+    updatePositionSliderUi(100.0f);
+    emit logFileEndReached();
+    emit suspendLogForReplay(false);
+    LinkManager::instance()->setConnectionsAllowed();
+}
+/// @brief Called when an error occurs during playback to reset playback system state.
+void QGCMAVLinkLogPlayer::_playbackError(void)
+{
+    pause();
+    logFile.close();
+    logFile.setFileName("");
+    ui->logFileNameLabel->setText(tr("No Flight Data selected"));    
+    // Disable playback controls
+    ui->playButton->setEnabled(false);
+    ui->speedSlider->setEnabled(false);
+    ui->positionSlider->setEnabled(false);
+    ui->speedLabel->setEnabled(false);
+    ui->logFileNameLabel->setEnabled(false);
+    ui->logStatsLabel->setEnabled(false);
+}
--- a/src/ui/QGCMAVLinkLogPlayer.h
+++ b/src/ui/QGCMAVLinkLogPlayer.h
@@ -37,29 +37,15 @@ public:
        return logFile.isOpen();
    }
-    /**
-     * @brief Set the last log file name
-     * @param filename
-     */
-    void setLastLogFile(const QString& filename) {
-        lastLogDirectory = filename;
-    }
 public slots:
    /** @brief Toggle between play and pause */
    void playPauseToggle();
-    /** @brief Play / pause the log */
-    void playPause(bool play);
    /** @brief Replay the logfile */
    void play();
    /** @brief Pause the log player. */
    void pause();
    /** @brief Reset the internal log player state, including the UI */
    void reset();
-    /** @brief Select logfile */
-    bool selectLogFile(const QString startDirectory);
-    /** @brief Select logfile */
-    bool selectLogFile();
    /** @brief Load log file */
    bool loadLogFile(const QString& file);
    /** @brief Jump to a position in the logfile */
@@ -73,6 +59,9 @@ signals:
    /** @brief Send ready bytes */
    void bytesReady(LinkInterface* link, const QByteArray& bytes);
    void logFileEndReached();
+    /// @brief Connected to the MAVLinkProtocol::suspendLogForReplay
+    void suspendLogForReplay(bool suspend);
 protected:
    quint64 playbackStartTime;     ///< The time when the logfile was first played back. This is used to pace out replaying the messages to fix long-term drift/skew. 0 indicates that the player hasn't initiated playback of this log file. In units of milliseconds since epoch UTC.
@@ -92,11 +81,10 @@ protected:
    unsigned int currPacketCount;
    static const int packetLen = MAVLINK_MAX_PACKET_LEN;
    static const int timeLen = sizeof(quint64);
-    QString lastLogDirectory;
    void changeEvent(QEvent *e);
-    void loadSettings();
+private slots:
-    void storeSettings();
+    void _selectLogFileForPlayback(void);
 private:
    Ui::QGCMAVLinkLogPlayer *ui;
@@ -130,6 +118,9 @@ private:
     * @return True if the new file position was successfully jumped to, false otherwise
     */
    bool jumpToPlaybackLocation(float percentage);
+    void _finishPlayback(void);
+    void _playbackError(void);
 };
 #endif // QGCMAVLINKLOGPLAYER_H
--- a/src/ui/QGCMAVLinkLogPlayer.ui
+++ b/src/ui/QGCMAVLinkLogPlayer.ui
@@ -36,13 +36,13 @@
   <item>
    <widget class="QToolButton" name="playButton">
     <property name="toolTip">
-      <string>Start to replay the logfile</string>
+      <string>Start to replay Flight Data</string>
     </property>
     <property name="statusTip">
-      <string>Start to replay the logfile</string>
+      <string>Start to replay Flight Data</string>
     </property>
     <property name="whatsThis">
-      <string>Start to replay the logfile</string>
+      <string>Start to replay Flight Data</string>
     </property>
     <property name="text">
      <string>...</string>
@@ -129,23 +129,23 @@
   <item>
    <widget class="QLabel" name="logFileNameLabel">
     <property name="text">
-      <string>No logfile selected..</string>
+      <string>No Flight Data selected..</string>
     </property>
    </widget>
   </item>
   <item>
    <widget class="QPushButton" name="selectFileButton">
     <property name="toolTip">
-      <string>Select the logfile to replay</string>
+      <string>Select the Flight Data to replay</string>
     </property>
     <property name="statusTip">
-      <string>Select the logfile to replay</string>
+      <string>Select the Flight Data to replay</string>
     </property>
     <property name="whatsThis">
-      <string>Select the logfile to replay</string>
+      <string>Select the Flight Data to replay</string>
     </property>
     <property name="text">
-      <string>Replay Logfile</string>
+      <string>Replay Flight Data</string>
     </property>
    </widget>
   </item>

--- a/src/ui/QGCStatusBar.cc
+++ b/src/ui/QGCStatusBar.cc
@@ -27,21 +27,15 @@ This file is part of the QGROUNDCONTROL project
 #include "QGCStatusBar.h"
 #include "UASManager.h"
 #include "MainWindow.h"
+#include "QGCCore.h"
 QGCStatusBar::QGCStatusBar(QWidget *parent) :
    QStatusBar(parent),
-    toggleLoggingButton(NULL),
    player(NULL),
    changed(true),
    lastLogDirectory(QStandardPaths::writableLocation(QStandardPaths::DesktopLocation))
 {
    setObjectName("QGC_STATUSBAR");
-    toggleLoggingButton = new QPushButton(tr("Log to file"), this);
-    toggleLoggingButton->setCheckable(true);
-    addPermanentWidget(toggleLoggingButton);
    loadSettings();
 }
@@ -58,58 +52,6 @@ void QGCStatusBar::setLogPlayer(QGCMAVLinkLogPlayer* player)
 {
    this->player = player;
    addPermanentWidget(player);
-    connect(toggleLoggingButton, SIGNAL(clicked(bool)), this, SLOT(logging(bool)));
-}
-void QGCStatusBar::logging(bool checked)
-{
-    // Stop logging in any case
-    MainWindow::instance()->getMAVLink()->enableLogging(false);
-    if (!checked && player)
-    {
-        player->setLastLogFile(lastLogDirectory);
-    }
-	// If the user is enabling logging
-    if (checked)
-    {
-		// Prompt the user for a filename/location to save to
-        QString fileName = QFileDialog::getSaveFileName(this, tr("Specify MAVLink log file to save to"), lastLogDirectory, tr("MAVLink Logfile (*.mavlink *.log *.bin);;"));
-		// Check that they didn't cancel out
-		if (fileName.isNull())
-		{
-            toggleLoggingButton->setChecked(false);
-			return;
-		}
-		// Make sure the file's named properly
-        if (!fileName.endsWith(".mavlink"))
-        {
-            fileName.append(".mavlink");
-        }
-		// Check that we can save the logfile
-        QFileInfo file(fileName);
-        if ((file.exists() && !file.isWritable()))
-        {
-            QMessageBox msgBox;
-            msgBox.setIcon(QMessageBox::Critical);
-            msgBox.setText(tr("The selected logfile is not writable"));
-            msgBox.setInformativeText(tr("Please make sure that the file %1 is writable or select a different file").arg(fileName));
-            msgBox.setStandardButtons(QMessageBox::Ok);
-            msgBox.setDefaultButton(QMessageBox::Ok);
-            msgBox.exec();
-        }
-		// Otherwise we're off and logging
-        else
-        {
-            MainWindow::instance()->getMAVLink()->setLogfileName(fileName);
-            MainWindow::instance()->getMAVLink()->enableLogging(true);
-            lastLogDirectory = file.absoluteDir().absolutePath(); //save last log directory
-        }
-    }
 }
 void QGCStatusBar::loadSettings()
@@ -132,5 +74,4 @@ void QGCStatusBar::storeSettings()
 QGCStatusBar::~QGCStatusBar()
 {
    storeSettings();
-    if (toggleLoggingButton) toggleLoggingButton->deleteLater();
 }
--- a/src/ui/QGCStatusBar.h
+++ b/src/ui/QGCStatusBar.h
@@ -43,8 +43,6 @@ public:
    ~QGCStatusBar();
 public slots:
-    /** @brief Start / stop logging */
-    void logging(bool checked);
    /** @brief Set log playing component */
    void setLogPlayer(QGCMAVLinkLogPlayer* player);
    virtual void paintEvent(QPaintEvent * event);
@@ -53,7 +51,6 @@ protected:
    void storeSettings();
    void loadSettings();
-    QPushButton* toggleLoggingButton;
    QGCMAVLinkLogPlayer* player;
    bool changed;
    QString lastLogDirectory;