Add initial gauge widget

src/UI/Dashboard.cpp

@@ -92,6 +92,14 @@ JSON::Dataset *Dashboard::getBar(const int index)
     return nullptr;
 }
 
+JSON::Dataset *Dashboard::getGauge(const int index)
+{
+    if (index < m_gaugeWidgets.count())
+        return m_gaugeWidgets.at(index);
+
+    return nullptr;
+}
+
 JSON::Dataset *Dashboard::getCompass(const int index)
 {
     if (index < m_compassWidgets.count())

src/UI/Dashboard.h

@@ -127,6 +127,7 @@ public:
     QFont monoFont() const;
     JSON::Group *getGroup(const int index);
     JSON::Dataset *getBar(const int index);
+    JSON::Dataset *getGauge(const int index);
     JSON::Dataset *getCompass(const int index);
 
     QString title();

src/Widgets/Compass.cpp

@@ -51,9 +51,11 @@ Compass::Compass(const int index)
     m_compass.setNeedle(
         new QwtCompassMagnetNeedle(QwtCompassMagnetNeedle::TriangleStyle));
 
-    // Set stylesheet
-    auto qss = QSS("background-color:%1", theme->datasetWindowBackground());
-    setStyleSheet(qss);
+    // Set window palette
+    QPalette windowPalette;
+    windowPalette.setColor(QPalette::Base, theme->datasetWindowBackground());
+    windowPalette.setColor(QPalette::Window, theme->datasetWindowBackground());
+    setPalette(windowPalette);
 
     // Add compass to layout
     m_layout.addWidget(&m_compass);

src/Widgets/Gauge.cpp

@@ -21,3 +21,118 @@
  */
 
 #include "Gauge.h"
+#include "UI/Dashboard.h"
+#include "Misc/ThemeManager.h"
+
+#include <QPainter>
+#include <QwtDialNeedle>
+#include <QwtRoundScaleDraw>
+#include <qwt_dial_needle.h>
+
+using namespace Widgets;
+
+//--------------------------------------------------------------------------------------------------
+// Gauge/Speedometer implementation (based on Qwt examples)
+//--------------------------------------------------------------------------------------------------
+
+GaugeObject::GaugeObject(QWidget *parent)
+    : QwtDial(parent)
+{
+    setReadOnly(true);
+    setWrapping(false);
+
+    // Set gauge origin & min/max angles
+    setOrigin(135);
+    setScaleArc(0, 270);
+
+    QwtDialSimpleNeedle *needle = new QwtDialSimpleNeedle(
+        QwtDialSimpleNeedle::Arrow, true, Qt::red, QColor(Qt::gray).lighter(130));
+    setNeedle(needle);
+}
+
+QString GaugeObject::label() const
+{
+    return m_label;
+}
+
+void GaugeObject::setLabel(const QString &label)
+{
+    m_label = label;
+    update();
+}
+
+void GaugeObject::drawScaleContents(QPainter *painter, const QPointF &center,
+                                    double radius) const
+{
+    QRectF rect(0.0, 0.0, 2.0 * radius, 2.0 * radius - 10.0);
+    rect.moveCenter(center);
+
+    const QColor color = palette().color(QPalette::Text);
+    painter->setPen(color);
+
+    const int flags = Qt::AlignBottom | Qt::AlignHCenter;
+    painter->drawText(rect, flags, m_label);
+}
+
+//--------------------------------------------------------------------------------------------------
+// Gauge widget implementation
+//--------------------------------------------------------------------------------------------------
+
+Gauge::Gauge(const int index)
+    : m_index(index)
+{
+    // Get pointers to Serial Studio modules
+    auto dash = UI::Dashboard::getInstance();
+    auto theme = Misc::ThemeManager::getInstance();
+
+    // Invalid index, abort initialization
+    if (m_index < 0 || m_index >= dash->gaugeCount())
+        return;
+
+    // Configure gauge
+    m_gauge.setFont(dash->monoFont());
+
+    // Set gauge scale (lazy widgets only)
+#ifdef LAZY_WIDGETS
+    auto dataset = dash->getGauge(m_index);
+    if (dataset)
+    {
+        m_gauge.setScale(dataset->min(), dataset->max());
+        if (!dataset->units().isEmpty())
+            m_gauge.setLabel(dataset->units());
+    }
+#endif
+
+    // Set window palette
+    QPalette windowPalette;
+    windowPalette.setColor(QPalette::Base, theme->datasetWindowBackground());
+    windowPalette.setColor(QPalette::Window, theme->datasetWindowBackground());
+    setPalette(windowPalette);
+
+    // Add gauge to layout
+    m_layout.addWidget(&m_gauge);
+    m_layout.setContentsMargins(8, 8, 8, 8);
+    setLayout(&m_layout);
+
+    // React to dashboard events
+    connect(dash, SIGNAL(updated()), this, SLOT(update()));
+}
+
+void Gauge::update()
+{
+    // Widget not enabled, do nothing
+    if (!isEnabled())
+        return;
+
+    // Update compass heading
+    auto dataset = UI::Dashboard::getInstance()->getGauge(m_index);
+    if (dataset)
+    {
+#ifndef LAZY_WIDGETS
+        m_gauge.setScale(dataset->min(), dataset->max());
+        if (!dataset->units().isEmpty())
+            m_gauge.setLabel(dataset->units());
+#endif
+        m_gauge.setValue(dataset->value().toDouble());
+    }
+}

src/Widgets/Gauge.h

@@ -26,12 +26,40 @@
 #include <QWidget>
 #include <QwtDial>
 #include <QwtDialNeedle>
+#include <QVBoxLayout>
 
 namespace Widgets
 {
+class GaugeObject : public QwtDial
+{
+public:
+    GaugeObject(QWidget *parent = nullptr);
+
+    QString label() const;
+    void setLabel(const QString &label);
+
+protected:
+    virtual void drawScaleContents(QPainter *painter, const QPointF &center,
+                                   double radius) const QWT_OVERRIDE;
+
+private:
+    QString m_label;
+};
+
 class Gauge : public QWidget
 {
     Q_OBJECT
+
+public:
+    Gauge(const int index = -1);
+
+private slots:
+    void update();
+
+private:
+    int m_index;
+    GaugeObject m_gauge;
+    QVBoxLayout m_layout;
 };
 }
 

src/Widgets/WidgetLoader.cpp

@@ -249,7 +249,8 @@ void WidgetLoader::setWidgetIndex(const int index)
                 m_window.setCentralWidget(new Bar(relativeIndex()));
                 break;
             case UI::Dashboard::WidgetType::Gauge:
-                m_widget = new QPushButton("Gauge");
+                m_widget = new Gauge(relativeIndex());
+                m_window.setCentralWidget(new Gauge(relativeIndex()));
                 break;
             case UI::Dashboard::WidgetType::Thermometer:
                 m_widget = new QPushButton("Thermometer");