Allow replacing instrument widget with custom widget

src/FlightDisplay/FlightDisplayViewWidgets.qml

@@ -48,6 +48,21 @@ Item {
     }
 
     function _setInstrumentWidget() {
+        if(QGroundControl.corePlugin.options.instrumentWidget.source.toString().length) {
+            instrumentsLoader.source = QGroundControl.corePlugin.options.instrumentWidget.source
+            switch(QGroundControl.corePlugin.options.instrumentWidget.widgetPosition) {
+            case CustomInstrumentWidget.POS_TOP_RIGHT:
+                instrumentsLoader.state  = "topMode"
+                break;
+            case CustomInstrumentWidget.POS_BOTTOM_RIGHT:
+                instrumentsLoader.state  = "bottomMode"
+                break;
+            case CustomInstrumentWidget.POS_CENTER_RIGHT:
+            default:
+                instrumentsLoader.state  = "centerMode"
+                break;
+            }
+        } else {
             var useAlternateInstruments = QGroundControl.virtualTabletJoystick || ScreenTools.isTinyScreen
             if(useAlternateInstruments) {
                 instrumentsLoader.source = "qrc:/qml/QGCInstrumentWidgetAlternate.qml"
@@ -57,6 +72,7 @@ Item {
                 instrumentsLoader.state  = "centerMode"
             }
         }
+    }
 
     Connections {
         target: QGroundControl
@@ -108,6 +124,7 @@ Item {
                 AnchorChanges {
                     target:                 instrumentsLoader
                     anchors.verticalCenter: undefined
+                    anchors.bottom:         undefined
                     anchors.top:            _root ? _root.top : undefined
                 }
             },
@@ -116,8 +133,18 @@ Item {
                 AnchorChanges {
                     target:                 instrumentsLoader
                     anchors.top:            undefined
+                    anchors.bottom:         undefined
                     anchors.verticalCenter: _root ? _root.verticalCenter : undefined
                 }
+            },
+            State {
+                name:   "bottomMode"
+                AnchorChanges {
+                    target:                 instrumentsLoader
+                    anchors.top:            undefined
+                    anchors.verticalCenter: undefined
+                    anchors.bottom:         _root ? _root.bottom : undefined
+                }
             }
         ]
     }

src/api/QGCOptions.cc

@@ -8,6 +8,7 @@
  ****************************************************************************/
 
 #include "QGCOptions.h"
+#include <QtQml>
 
 /// @file
 ///     @brief Core Plugin Interface for QGroundControl - Application Options
@@ -15,5 +16,23 @@
 
 QGCOptions::QGCOptions(QObject* parent)
     : QObject(parent)
+    , _defaultInstrumentWidget(NULL)
 {
+    qmlRegisterUncreatableType<CustomInstrumentWidget>("QGroundControl", 1, 0, "CustomInstrumentWidget", "Reference only");
 }
+
+CustomInstrumentWidget*
+QGCOptions::instrumentWidget()
+{
+    if(!_defaultInstrumentWidget) {
+        _defaultInstrumentWidget = new CustomInstrumentWidget(this);
+    }
+    return _defaultInstrumentWidget;
+}
+
+CustomInstrumentWidget::CustomInstrumentWidget(QObject* parent)
+    : QObject(parent)
+{
+}
+
+

src/api/QGCOptions.h

@@ -11,11 +11,13 @@
 
 #include <QObject>
 #include <QString>
+#include <QUrl>
 
 /// @file
 ///     @brief Core Plugin Interface for QGroundControl - Application Options
 ///     @author Gus Grubba <mavlink@grubba.com>
 
+class CustomInstrumentWidget;
 class QGCOptions : public QObject
 {
     Q_OBJECT
@@ -32,6 +34,8 @@ public:
     Q_PROPERTY(double   toolbarHeightMultiplier     READ toolbarHeightMultiplier    CONSTANT)
     Q_PROPERTY(double   defaultFontPointSize        READ defaultFontPointSize       CONSTANT)
     Q_PROPERTY(bool     enablePlanViewSelector      READ enablePlanViewSelector     CONSTANT)
+    Q_PROPERTY(CustomInstrumentWidget*  instrumentWidget READ instrumentWidget      CONSTANT)
+
 
     //! Should QGC hide its settings menu and colapse it into one single menu (Settings and Vehicle Setup)?
     /*!
@@ -83,4 +87,32 @@ public:
         @return True or false
     */
     virtual bool        enablePlanViewSelector      () { return true; }
+    //! Provides an alternate instrument widget for the Fly View
+    /*!
+        @return An alternate widget (see QGCInstrumentWidget.qml, the default widget)
+    */
+    virtual CustomInstrumentWidget* instrumentWidget();
+private:
+    CustomInstrumentWidget* _defaultInstrumentWidget;
+};
+
+//-----------------------------------------------------------------------------
+class CustomInstrumentWidget : public QObject
+{
+    Q_OBJECT
+public:
+    //-- Widget Position
+    enum Pos {
+        POS_TOP_RIGHT           = 0,
+        POS_CENTER_RIGHT        = 1,
+        POS_BOTTOM_RIGHT        = 2,
+    };
+    Q_ENUMS(Pos)
+    CustomInstrumentWidget(QObject* parent = NULL);
+    Q_PROPERTY(QUrl     source  READ source CONSTANT)
+    Q_PROPERTY(Pos      widgetPosition              READ widgetPosition             NOTIFY widgetPositionChanged)
+    virtual QUrl        source                      () { return QUrl(); }
+    virtual Pos         widgetPosition              () { return POS_CENTER_RIGHT; }
+signals:
+    void widgetPositionChanged  ();
 };

src/ui/AppSettings.qml

@@ -35,8 +35,8 @@ Rectangle {
     QGCPalette { id: qgcPal }
 
     Component.onCompleted: {
-        //-- Default to General Settings
-        __rightPanel.source = "GeneralSettings.qml"
+        //-- Default Settings
+        __rightPanel.source = QGroundControl.corePlugin.settings[QGroundControl.corePlugin.defaltSettings].url
     }
 
     QGCFlickable {