Replace usage of QMessageBox with a QML window.

qgroundcontrol.qrc

@@ -28,6 +28,7 @@
         <file alias="DebugWindow.qml">src/ui/preferences/DebugWindow.qml</file>
         <file alias="ESP8266Component.qml">src/AutoPilotPlugins/Common/ESP8266Component.qml</file>
         <file alias="ESP8266ComponentSummary.qml">src/AutoPilotPlugins/Common/ESP8266ComponentSummary.qml</file>
+        <file alias="ExitWithErrorWindow.qml">src/ui/ExitWithErrorWindow.qml</file>
         <file alias="FirmwareUpgrade.qml">src/VehicleSetup/FirmwareUpgrade.qml</file>
         <file alias="FlightDisplayViewDummy.qml">src/FlightDisplay/FlightDisplayViewDummy.qml</file>
         <file alias="FlightDisplayViewUVC.qml">src/FlightDisplay/FlightDisplayViewUVC.qml</file>

src/QGCApplication.cc

@@ -26,11 +26,6 @@
 #include <QStringListModel>
 #include <QRegularExpression>
 #include <QFontDatabase>
-#ifdef Q_OS_LINUX
-#ifndef __mobile__
-    #include <QMessageBox>
-#endif
-#endif
 
 #ifdef QGC_ENABLE_BLUETOOTH
 #include <QBluetoothLocalDevice>
@@ -164,42 +159,33 @@ QGCApplication::QGCApplication(int &argc, char* argv[], bool unitTesting)
     , _runningUnitTests         (unitTesting)
 {
     _app = this;
-    // Setup for network proxy support
-    QNetworkProxyFactory::setUseSystemConfiguration(true);
-
 #ifdef Q_OS_LINUX
 #ifndef __mobile__
     if (!_runningUnitTests) {
         if (getuid() == 0) {
-            QMessageBox msgBox;
-            msgBox.setInformativeText(tr("You are running %1 as root. "
-                                         "You should not do this since it will cause other issues with %1. "
-                                         "%1 will now exit. "
-                                         "If you are having serial port issues on Ubuntu, execute the following commands to fix most issues:\n"
-                                         "sudo usermod -a -G dialout $USER\n"
-                                         "sudo apt-get remove modemmanager").arg(qgcApp()->applicationName()));
-            msgBox.setStandardButtons(QMessageBox::Ok);
-            msgBox.setDefaultButton(QMessageBox::Ok);
-            msgBox.exec();
-            _exit(0);
+            _exitWithError(QString(
+                tr("You are running %1 as root. "
+                    "You should not do this since it will cause other issues with %1."
+                    "%1 will now exit.<br/><br/>"
+                    "If you are having serial port issues on Ubuntu, execute the following commands to fix most issues:<br/>"
+                    "<pre>sudo usermod -a -G dialout $USER<br/>"
+                    "sudo apt-get remove modemmanager</pre>").arg(qgcApp()->applicationName())));
+            return;
         }
-
         // Determine if we have the correct permissions to access USB serial devices
         QFile permFile("/etc/group");
         if(permFile.open(QIODevice::ReadOnly)) {
             while(!permFile.atEnd()) {
                 QString line = permFile.readLine();
                 if (line.contains("dialout") && !line.contains(getenv("USER"))) {
-                    QMessageBox msgBox;
-                    msgBox.setInformativeText("The current user does not have the correct permissions to access serial devices. "
-                                              "You should also remove modemmanager since it also interferes. "
-                                              "If you are using Ubuntu, execute the following commands to fix these issues:\n"
-                                              "sudo usermod -a -G dialout $USER\n"
-                                              "sudo apt-get remove modemmanager");
-                    msgBox.setStandardButtons(QMessageBox::Ok);
-                    msgBox.setDefaultButton(QMessageBox::Ok);
-                    msgBox.exec();
-                    break;
+                    permFile.close();
+                    _exitWithError(QString(
+                        tr("The current user does not have the correct permissions to access serial devices. "
+                           "You should also remove modemmanager since it also interferes.<br/><br/>"
+                           "If you are using Ubuntu, execute the following commands to fix these issues:<br/>"
+                           "<pre>sudo usermod -a -G dialout $USER<br/>"
+                           "sudo apt-get remove modemmanager</pre>")));
+                    return;
                 }
             }
             permFile.close();
@@ -208,6 +194,9 @@ QGCApplication::QGCApplication(int &argc, char* argv[], bool unitTesting)
 #endif
 #endif
 
+    // Setup for network proxy support
+    QNetworkProxyFactory::setUseSystemConfiguration(true);
+
     // Parse command line options
 
     bool fClearSettingsOptions = false; // Clear stored settings
@@ -348,6 +337,17 @@ QGCApplication::QGCApplication(int &argc, char* argv[], bool unitTesting)
     _checkForNewVersion();
 }
 
+void QGCApplication::_exitWithError(QString errorMessage)
+{
+    _error = true;
+    QQmlApplicationEngine* pEngine = new QQmlApplicationEngine(this);
+    pEngine->addImportPath("qrc:/qml");
+    pEngine->rootContext()->setContextProperty("errorMessage", errorMessage);
+    pEngine->load(QUrl(QStringLiteral("qrc:/qml/ExitWithErrorWindow.qml")));
+    // Exit main application when last window is closed
+    connect(this, &QGCApplication::lastWindowClosed, this, QGCApplication::quit);
+}
+
 void QGCApplication::setLanguage()
 {
     _locale = QLocale::system();

src/QGCApplication.h

@@ -145,6 +145,8 @@ public:
 
     static QGCApplication*  _app;   ///< Our own singleton. Should be reference directly by qgcApp
 
+    bool    isErrorState()  { return _error; }
+
 public:
     // Although public, these methods are internal and should only be called by UnitTest code
 
@@ -166,6 +168,7 @@ private slots:
 private:
     QObject*    _rootQmlObject          ();
     void        _checkForNewVersion     ();
+    void        _exitWithError          (QString errorMessage);
 
 
     bool _runningUnitTests; ///< true: running unit tests, false: normal app
@@ -190,6 +193,7 @@ private:
     QTranslator         _QGCTranslator;
     QTranslator         _QGCTranslatorQt;
     QLocale             _locale;
+    bool                _error                  = false;
 
     static const char* _settingsVersionKey;             ///< Settings key which hold settings version
     static const char* _deleteAllSettingsKey;           ///< If this settings key is set on boot, all settings will be deleted

src/main.cc

@@ -328,6 +328,10 @@ int main(int argc, char *argv[])
     QCoreApplication::setAttribute(Qt::AA_UseHighDpiPixmaps);
     QGCApplication* app = new QGCApplication(argc, argv, runUnitTests);
     Q_CHECK_PTR(app);
+    if(app->isErrorState()) {
+        app->exec();
+        return -1;
+    }
 
 #ifdef Q_OS_LINUX
     QApplication::setWindowIcon(QIcon(":/res/resources/icons/qgroundcontrol.ico"));

src/ui/ExitWithErrorWindow.qml

@@ -0,0 +1,54 @@
+/****************************************************************************
+ *
+ *   (c) 2009-2016 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+ *
+ * QGroundControl is licensed according to the terms in the file
+ * COPYING.md in the root of the source code directory.
+ *
+ ****************************************************************************/
+
+import QtQuick          2.11
+import QtQuick.Controls 2.4
+import QtQuick.Dialogs  1.3
+import QtQuick.Layouts  1.11
+import QtQuick.Window   2.11
+
+ApplicationWindow {
+    id:             errorWindow
+    minimumWidth:   messageArea.width  + 60
+    minimumHeight:  messageArea.height + 60
+    width:          messageArea.width  + 60
+    height:         messageArea.height + 60
+    visible:        true
+
+    //-------------------------------------------------------------------------
+    //-- Main, full window background (Fly View)
+    background: Item {
+        id:             rootBackground
+        anchors.fill:   parent
+        Rectangle {
+            anchors.fill:   parent
+            color:          "#000000"
+        }
+    }
+
+    Column {
+        id:                 messageArea
+        spacing:            20
+        anchors.centerIn:   parent
+        Label {
+            width:          600
+            text:           errorMessage
+            color:          "#eecc44"
+            wrapMode:       Text.WordWrap
+            anchors.horizontalCenter: parent.horizontalCenter
+        }
+        Button {
+            text:           qsTr("Close")
+            highlighted:    true
+            onClicked:      errorWindow.close()
+            anchors.horizontalCenter: parent.horizontalCenter
+        }
+    }
+
+}