diff --git a/src/GAudioOutput.cc b/src/GAudioOutput.cc
index 35aef2f..9d479bc 100644
--- a/src/GAudioOutput.cc
+++ b/src/GAudioOutput.cc
@@ -223,7 +223,7 @@ bool GAudioOutput::say(QString text, int severity)
             text = "\\" + text;
             QStdWString str = text.toStdWString();
             unsigned char str2[1024] = {};
-            memcpy(str2, text.toAscii().data(), str.length());
+            memcpy(str2, text.toLatin1().data(), str.length());
             SpeakString(str2);
             res = true;
 #endif // Q_OS_MAC
diff --git a/src/apps/qgcvideo/QGCVideoWidget.cc b/src/apps/qgcvideo/QGCVideoWidget.cc
index 8fc9b85..ba0be9c 100644
--- a/src/apps/qgcvideo/QGCVideoWidget.cc
+++ b/src/apps/qgcvideo/QGCVideoWidget.cc
@@ -151,7 +151,7 @@ QGCVideoWidget::QGCVideoWidget(QWidget* parent)
 
     // Fill with black background
     QImage fill = QImage(640, 480, QImage::Format_Indexed8);
-    fill.setNumColors(3);
+    fill.setColorCount(3);
     fill.setColor(0, qRgb(0, 0, 0));
     fill.setColor(1, qRgb(0, 0, 0));
     fill.setColor(2, qRgb(0, 0, 0));
@@ -1136,7 +1136,7 @@ void QGCVideoWidget::commitRawDataToGL()
         QImage* newImage = new QImage(rawImage, receivedWidth, receivedHeight, format);
         if (format == QImage::Format_Indexed8) {
             // Create matching color table
-            newImage->setNumColors(256);
+            newImage->setColorCount(256);
             for (int i = 0; i < 256; i++) {
                 newImage->setColor(i, qRgb(i, i, i));
                 //qDebug() << __FILE__ << __LINE__ << std::hex << i;
diff --git a/src/comm/QGCFlightGearLink.cc b/src/comm/QGCFlightGearLink.cc
index ce54a3e..f570adf 100644
--- a/src/comm/QGCFlightGearLink.cc
+++ b/src/comm/QGCFlightGearLink.cc
@@ -236,7 +236,7 @@ void QGCFlightGearLink::updateControls(quint64 time, float rollAilerons, float p
     {
         QString state("%1\t%2\t%3\t%4\t%5\n");
         state = state.arg(rollAilerons).arg(pitchElevator).arg(yawRudder).arg(true).arg(throttle);
-        writeBytes(state.toAscii().constData(), state.length());
+        writeBytes(state.toLatin1().constData(), state.length());
         //qDebug() << "Updated controls" << rollAilerons << pitchElevator << yawRudder << throttle;
         //qDebug() << "Updated controls" << state;
     }
diff --git a/src/comm/QGCJSBSimLink.cc b/src/comm/QGCJSBSimLink.cc
index 947161d..56f03d7 100644
--- a/src/comm/QGCJSBSimLink.cc
+++ b/src/comm/QGCJSBSimLink.cc
@@ -257,7 +257,7 @@ void QGCJSBSimLink::updateControls(quint64 time, float rollAilerons, float pitch
     {
         QString state("%1\t%2\t%3\t%4\t%5\n");
         state = state.arg(rollAilerons).arg(pitchElevator).arg(yawRudder).arg(true).arg(throttle);
-        writeBytes(state.toAscii().constData(), state.length());
+        writeBytes(state.toLatin1().constData(), state.length());
     }
     else
     {
diff --git a/src/comm/QGCParamID.h b/src/comm/QGCParamID.h
index 2df351f..44f9dde 100644
--- a/src/comm/QGCParamID.h
+++ b/src/comm/QGCParamID.h
@@ -72,7 +72,7 @@ public:
         return static_cast<const QString>(data);
     }
     int8_t* toInt8_t() const {
-        return (int8_t*)data.toAscii().data();
+        return (int8_t*)data.toLatin1().data();
     }
 
 protected:
diff --git a/src/comm/QGCXPlaneLink.cc b/src/comm/QGCXPlaneLink.cc
index f829b7e..106e3c6 100644
--- a/src/comm/QGCXPlaneLink.cc
+++ b/src/comm/QGCXPlaneLink.cc
@@ -226,8 +226,8 @@ void QGCXPlaneLink::run()
     }
 
     ip.index = 0;
-    strncpy(ip.str_ipad_them, localAddrStr.toAscii(), qMin((int)sizeof(ip.str_ipad_them), 16));
-    strncpy(ip.str_port_them, localPortStr.toAscii(), qMin((int)sizeof(ip.str_port_them), 6));
+    strncpy(ip.str_ipad_them, localAddrStr.toLatin1(), qMin((int)sizeof(ip.str_ipad_them), 16));
+    strncpy(ip.str_port_them, localPortStr.toLatin1(), qMin((int)sizeof(ip.str_port_them), 6));
     ip.use_ip = 1;
 
     writeBytes((const char*)&ip, sizeof(ip));
@@ -261,7 +261,6 @@ void QGCXPlaneLink::run()
 
     emit simulationDisconnected();
     emit simulationConnected(false);
-    emit finished();
 }
 
 void QGCXPlaneLink::setPort(int localPort)
diff --git a/src/comm/XbeeLink.cpp b/src/comm/XbeeLink.cpp
index 767da68..337c961 100644
--- a/src/comm/XbeeLink.cpp
+++ b/src/comm/XbeeLink.cpp
@@ -73,7 +73,7 @@ bool XbeeLink::setPortName(QString portName)
 		m_portName = new char[this->m_portNameLength];
 		for(int i=0;i<list[0].size();i++)
 		{
-			this->m_portName[i]=list[0][i].toAscii();
+			this->m_portName[i]=list[0][i].toLatin1();
 		}
 		this->m_portName[list[0].size()] = '\0';
 	}
diff --git a/src/uas/UAS.cc b/src/uas/UAS.cc
index da9c884..652ad6a 100644
--- a/src/uas/UAS.cc
+++ b/src/uas/UAS.cc
@@ -2563,7 +2563,7 @@ void UAS::setParameter(const int compId, const QString& paramId, const QVariant&
             switch ((int)value.type())
             {
             case QVariant::Char:
-                union_value.param_float = (unsigned char)value.toChar().toAscii();
+                union_value.param_float = (unsigned char)value.toChar().toLatin1();
                 p.param_type = MAV_PARAM_TYPE_INT8;
                 break;
             case QVariant::Int:
@@ -2588,7 +2588,7 @@ void UAS::setParameter(const int compId, const QString& paramId, const QVariant&
             switch ((int)value.type())
             {
             case QVariant::Char:
-                union_value.param_int8 = (unsigned char)value.toChar().toAscii();
+                union_value.param_int8 = (unsigned char)value.toChar().toLatin1();
                 p.param_type = MAV_PARAM_TYPE_INT8;
                 break;
             case QVariant::Int:
@@ -2621,7 +2621,7 @@ void UAS::setParameter(const int compId, const QString& paramId, const QVariant&
             // String characters
             if ((int)i < paramId.length())
             {
-                p.param_id[i] = paramId.toAscii()[i];
+                p.param_id[i] = paramId.toLatin1()[i];
             }
             else
             {
diff --git a/src/ui/CameraView.cc b/src/ui/CameraView.cc
index 13bc86b..f23e96f 100644
--- a/src/ui/CameraView.cc
+++ b/src/ui/CameraView.cc
@@ -49,7 +49,7 @@ CameraView::CameraView(int width, int height, int depth, int channels, QWidget*
 
     // Fill with black background
     QImage fill = QImage(width, height, QImage::Format_Indexed8);
-    fill.setNumColors(1);
+    fill.setColorCount(1);
     fill.setColor(0, qRgb(70, 200, 70));
     fill.fill(CameraView::initialColor);
     glImage = QGLWidget::convertToGLFormat(fill);
@@ -104,7 +104,7 @@ void CameraView::setImageSize(int width, int height, int depth, int channels)
         if (depth <= 8 && channels == 1) {
             image = new QImage(receivedWidth, receivedHeight, QImage::Format_Indexed8);
             // Create matching color table
-            image->setNumColors(256);
+            image->setColorCount(256);
             for (int i = 0; i < 256; i++) {
                 image->setColor(i, qRgb(i, i, i));
                 //qDebug() << __FILE__ << __LINE__ << std::hex << i;
@@ -162,7 +162,7 @@ void CameraView::commitRawDataToGL()
         QImage* newImage = new QImage(rawImage, receivedWidth, receivedHeight, format);
         if (format == QImage::Format_Indexed8) {
             // Create matching color table
-            newImage->setNumColors(256);
+            newImage->setColorCount(256);
             for (int i = 0; i < 256; i++) {
                 newImage->setColor(i, qRgb(i, i, i));
                 //qDebug() << __FILE__ << __LINE__ << std::hex << i;
diff --git a/src/ui/HUD.cc b/src/ui/HUD.cc
index 90b1ca0..2c13dc5 100644
--- a/src/ui/HUD.cc
+++ b/src/ui/HUD.cc
@@ -1212,7 +1212,7 @@ void HUD::setImageSize(int width, int height, int depth, int channels)
         if (depth <= 8 && channels == 1) {
             image = new QImage(receivedWidth, receivedHeight, QImage::Format_Indexed8);
             // Create matching color table
-            image->setNumColors(256);
+            image->setColorCount(256);
             for (int i = 0; i < 256; i++) {
                 image->setColor(i, qRgb(i, i, i));
                 //qDebug() << __FILE__ << __LINE__ << std::hex << i;
@@ -1277,7 +1277,7 @@ void HUD::commitRawDataToGL()
         QImage* newImage = new QImage(rawImage, receivedWidth, receivedHeight, format);
         if (format == QImage::Format_Indexed8) {
             // Create matching color table
-            newImage->setNumColors(256);
+            newImage->setColorCount(256);
             for (int i = 0; i < 256; i++) {
                 newImage->setColor(i, qRgb(i, i, i));
                 //qDebug() << __FILE__ << __LINE__ << std::hex << i;
diff --git a/src/ui/MainWindow.cc b/src/ui/MainWindow.cc
index eb6e525..d38db5f 100644
--- a/src/ui/MainWindow.cc
+++ b/src/ui/MainWindow.cc
@@ -71,6 +71,7 @@ This file is part of the QGROUNDCONTROL project
 #include "SerialSettingsDialog.h"
 #include "terminalconsole.h"
 #include "menuactionhelper.h"
+#include <QDesktopWidget>
 
 // Add support for the MAVLink generator UI if it's been requested.
 #ifdef QGC_MAVGEN_ENABLED
@@ -366,23 +367,23 @@ void MainWindow::init()
 
     // Set OS dependent keyboard shortcuts for the main window, non OS dependent shortcuts are set in MainWindow.ui
 #ifdef Q_OS_MACX
-    ui.actionFlightView->setShortcut(QApplication::translate("MainWindow", "Meta+1", 0, QApplication::UnicodeUTF8));
-    ui.actionMissionView->setShortcut(QApplication::translate("MainWindow", "Meta+2", 0, QApplication::UnicodeUTF8));
-    ui.actionHardwareConfig->setShortcut(QApplication::translate("MainWindow", "Meta+3", 0, QApplication::UnicodeUTF8));
-    ui.actionSimulationView->setShortcut(QApplication::translate("MainWindow", "Meta+4", 0, QApplication::UnicodeUTF8));
-    ui.actionEngineersView->setShortcut(QApplication::translate("MainWindow", "Meta+5", 0, QApplication::UnicodeUTF8));
-    ui.actionMavlinkView->setShortcut(QApplication::translate("MainWindow", "Meta+M", 0, QApplication::UnicodeUTF8));
-    ui.actionUnconnectedView->setShortcut(QApplication::translate("MainWindow", "Meta+U", 0, QApplication::UnicodeUTF8));
-    ui.actionFullscreen->setShortcut(QApplication::translate("MainWindow", "Meta+Return", 0, QApplication::UnicodeUTF8));
+    ui.actionFlightView->setShortcut(QApplication::translate("MainWindow", "Meta+1", 0));
+    ui.actionMissionView->setShortcut(QApplication::translate("MainWindow", "Meta+2", 0));
+    ui.actionHardwareConfig->setShortcut(QApplication::translate("MainWindow", "Meta+3", 0));
+    ui.actionSimulationView->setShortcut(QApplication::translate("MainWindow", "Meta+4", 0));
+    ui.actionEngineersView->setShortcut(QApplication::translate("MainWindow", "Meta+5", 0));
+    ui.actionMavlinkView->setShortcut(QApplication::translate("MainWindow", "Meta+M", 0));
+    ui.actionUnconnectedView->setShortcut(QApplication::translate("MainWindow", "Meta+U", 0));
+    ui.actionFullscreen->setShortcut(QApplication::translate("MainWindow", "Meta+Return", 0));
 #else
-    ui.actionFlightView->setShortcut(QApplication::translate("MainWindow", "Ctrl+1", 0, QApplication::UnicodeUTF8));
-    ui.actionMissionView->setShortcut(QApplication::translate("MainWindow", "Ctrl+2", 0, QApplication::UnicodeUTF8));
-    ui.actionHardwareConfig->setShortcut(QApplication::translate("MainWindow", "Ctrl+3", 0, QApplication::UnicodeUTF8));
-    ui.actionSimulationView->setShortcut(QApplication::translate("MainWindow", "Ctrl+4", 0, QApplication::UnicodeUTF8));
-    ui.actionEngineersView->setShortcut(QApplication::translate("MainWindow", "Ctrl+5", 0, QApplication::UnicodeUTF8));
-    ui.actionMavlinkView->setShortcut(QApplication::translate("MainWindow", "Ctrl+M", 0, QApplication::UnicodeUTF8));
-    ui.actionUnconnectedView->setShortcut(QApplication::translate("MainWindow", "Ctrl+U", 0, QApplication::UnicodeUTF8));
-    ui.actionFullscreen->setShortcut(QApplication::translate("MainWindow", "Ctrl+Return", 0, QApplication::UnicodeUTF8));
+    ui.actionFlightView->setShortcut(QApplication::translate("MainWindow", "Ctrl+1", 0));
+    ui.actionMissionView->setShortcut(QApplication::translate("MainWindow", "Ctrl+2", 0));
+    ui.actionHardwareConfig->setShortcut(QApplication::translate("MainWindow", "Ctrl+3", 0));
+    ui.actionSimulationView->setShortcut(QApplication::translate("MainWindow", "Ctrl+4", 0));
+    ui.actionEngineersView->setShortcut(QApplication::translate("MainWindow", "Ctrl+5", 0));
+    ui.actionMavlinkView->setShortcut(QApplication::translate("MainWindow", "Ctrl+M", 0));
+    ui.actionUnconnectedView->setShortcut(QApplication::translate("MainWindow", "Ctrl+U", 0));
+    ui.actionFullscreen->setShortcut(QApplication::translate("MainWindow", "Ctrl+Return", 0));
 #endif
 
     connect(&windowNameUpdateTimer, SIGNAL(timeout()), this, SLOT(configureWindowName()));
@@ -899,7 +900,7 @@ void MainWindow::addToCentralStackedWidget(QWidget* widget, VIEW_SECTIONS viewSe
 void MainWindow::showCentralWidget()
 {
     QAction* act = qobject_cast<QAction *>(sender());
-    QWidget* widget = qVariantValue<QWidget *>(act->data());
+    QWidget* widget = act->data().value<QWidget *>();
     centerStack->setCurrentWidget(widget);
 }
 
@@ -1185,7 +1186,7 @@ void MainWindow::saveScreen()
 
     if (!screenFileName.isEmpty())
     {
-        window.save(screenFileName, format.toAscii());
+        window.save(screenFileName, format.toLatin1());
     }
 }
 void MainWindow::enableDockWidgetTitleBars(bool enabled)
diff --git a/src/ui/QGCSettingsWidget.cc b/src/ui/QGCSettingsWidget.cc
index fa61cc7..0d7539d 100644
--- a/src/ui/QGCSettingsWidget.cc
+++ b/src/ui/QGCSettingsWidget.cc
@@ -20,7 +20,7 @@ QGCSettingsWidget::QGCSettingsWidget(QWidget *parent, Qt::WindowFlags flags) :
 
     // Center the window on the screen.
     QRect position = frameGeometry();
-    position.moveCenter(QDesktopWidget().availableGeometry().center());
+    position.moveCenter(QApplication::desktop()->availableGeometry().center());
     move(position.topLeft());
 
     // Add all protocols
diff --git a/src/ui/map3D/Q3DWidget.cc b/src/ui/map3D/Q3DWidget.cc
index 54fc876..aa8918a 100644
--- a/src/ui/map3D/Q3DWidget.cc
+++ b/src/ui/map3D/Q3DWidget.cc
@@ -254,7 +254,7 @@ Q3DWidget::handleKeyPressEvent(QKeyEvent* event)
     {
         mOsgGW->getEventQueue()->keyPress(
             static_cast<osgGA::GUIEventAdapter::KeySymbol>(
-                *(event->text().toAscii().data())));
+                *(event->text().toLatin1().data())));
     }
 }
 
@@ -274,7 +274,7 @@ Q3DWidget::handleKeyReleaseEvent(QKeyEvent* event)
     {
         mOsgGW->getEventQueue()->keyRelease(
             static_cast<osgGA::GUIEventAdapter::KeySymbol>(
-                *(event->text().toAscii().data())));
+                *(event->text().toLatin1().data())));
     }
 }
 
diff --git a/src/ui/mavlink/QGCMAVLinkMessageSender.cc b/src/ui/mavlink/QGCMAVLinkMessageSender.cc
index fabf249..6a93ed1 100644
--- a/src/ui/mavlink/QGCMAVLinkMessageSender.cc
+++ b/src/ui/mavlink/QGCMAVLinkMessageSender.cc
@@ -81,7 +81,7 @@ bool QGCMAVLinkMessageSender::sendMessage(unsigned int msgid)
                 {
                     // Single char
                     char* b = ((char*)(m+messageInfo[msgid].fields[fieldid].wire_offset));
-                    *b = field->data(1, Qt::DisplayRole).toChar().toAscii();
+                    *b = field->data(1, Qt::DisplayRole).toChar().toLatin1();
                 }
                 break;
             case MAVLINK_TYPE_UINT8_T:
@@ -100,7 +100,7 @@ bool QGCMAVLinkMessageSender::sendMessage(unsigned int msgid)
                 {
                     // Single value
                     uint8_t* u = (m+messageInfo[msgid].fields[fieldid].wire_offset);
-                    *u = field->data(1, Qt::DisplayRole).toChar().toAscii();
+                    *u = field->data(1, Qt::DisplayRole).toChar().toLatin1();
                 }
                 break;
             case MAVLINK_TYPE_INT8_T:
@@ -119,7 +119,7 @@ bool QGCMAVLinkMessageSender::sendMessage(unsigned int msgid)
                 {
                     // Single value
                     int8_t* u = reinterpret_cast<int8_t*>(m+messageInfo[msgid].fields[fieldid].wire_offset);
-                    *u = field->data(1, Qt::DisplayRole).toChar().toAscii();
+                    *u = field->data(1, Qt::DisplayRole).toChar().toLatin1();
                 }
                 break;
             case MAVLINK_TYPE_INT16_T: