Support dynamic change of font family

src/controls/Theme.qml

@@ -56,6 +56,7 @@ QtObject {
     property color visitedLinkBackgroundColor: "#2196F3"
 
     property real fontSize: FishUICore.ThemeManager.fontSize
+    property string fontFamily: FishUICore.ThemeManager.fontFamily
 
     property real smallRadius: 8.0
     property real mediumRadius: 10.0

src/fish-style/Label.qml

@@ -13,7 +13,7 @@ T.Label {
     renderType: Window.devicePixelRatio % 1 !== 0 ? Text.QtRendering : Text.NativeRendering
 
     font.capitalization: FishUI.Theme.defaultFont.capitalization
-    font.family: FishUI.Theme.defaultFont.family
+    font.family: FishUI.Theme.fontFamily
     font.italic: FishUI.Theme.defaultFont.italic
     font.letterSpacing: FishUI.Theme.defaultFont.letterSpacing
     font.pointSize: FishUI.Theme.fontSize

src/thememanager.cpp

@@ -36,6 +36,7 @@ ThemeManager::ThemeManager(QObject *parent)
     , m_accentColorIndex(-1)
     , m_accentColor(m_blueColor) // The default is blue
     , m_fontSize(9.0)
+    , m_fontFamily("Noto Sans")
 {
     QDBusServiceWatcher *serviceWatcher = new QDBusServiceWatcher(Service, QDBusConnection::sessionBus(),
                                                                   QDBusServiceWatcher::WatchForRegistration);
@@ -65,6 +66,9 @@ void ThemeManager::initData()
         m_fontSize = iface.property("systemFontPointSize").toReal();
         emit fontSizeChanged();
 
+        m_fontFamily = iface.property("systemFont").toString();
+        emit fontFamilyChanged();
+
         emit darkModeChanged();
     }
 }
@@ -80,6 +84,8 @@ void ThemeManager::initDBusSignals()
                                               this, SLOT(onDBusAccentColorChanged(int)));
         QDBusConnection::sessionBus().connect(Service, ObjectPath, Interface, "systemFontPointSizeChanged",
                                               this, SLOT(onDBusFontSizeChanged()));
+        QDBusConnection::sessionBus().connect(Service, ObjectPath, Interface, "systemFontChanged",
+                                              this, SLOT(onDBusFontFamilyChanged()));
     }
 }
 
@@ -107,6 +113,17 @@ void ThemeManager::onDBusFontSizeChanged()
     }
 }
 
+void ThemeManager::onDBusFontFamilyChanged()
+{
+    QDBusInterface iface(Service, ObjectPath, Interface, QDBusConnection::sessionBus(), this);
+
+    QString family = iface.property("systemFont").toString();
+    if (family != m_fontFamily) {
+        m_fontFamily = family;
+        emit fontFamilyChanged();
+    }
+}
+
 void ThemeManager::setAccentColor(int accentColorID)
 {
     if (m_accentColorIndex == accentColorID)

src/thememanager.h

@@ -46,6 +46,7 @@ class ThemeManager : public QObject
     Q_PROPERTY(QColor greyColor READ greyColor CONSTANT)
     Q_PROPERTY(qreal devicePixelRatio READ devicePixelRatio CONSTANT)
     Q_PROPERTY(qreal fontSize READ fontSize NOTIFY fontSizeChanged)
+    Q_PROPERTY(QString fontFamily READ fontFamily NOTIFY fontFamilyChanged)
 
 public:
     explicit ThemeManager(QObject *parent = nullptr);
@@ -56,6 +57,7 @@ public:
     QColor accentColor() { return m_accentColor; }
 
     qreal fontSize() { return m_fontSize; }
+    QString fontFamily() { return m_fontFamily; }
 
     QColor blueColor() { return m_blueColor; }
     QColor redColor() { return m_redColor; }
@@ -69,6 +71,7 @@ signals:
     void darkModeChanged();
     void accentColorChanged();
     void fontSizeChanged();
+    void fontFamilyChanged();
 
 private slots:
     void initData();
@@ -76,6 +79,7 @@ private slots:
     void onDBusDarkModeChanged(bool darkMode);
     void onDBusAccentColorChanged(int accentColorID);
     void onDBusFontSizeChanged();
+    void onDBusFontFamilyChanged();
 
 private:
     void setAccentColor(int accentColorID);
@@ -94,6 +98,7 @@ private:
 
     QColor m_accentColor;
     qreal m_fontSize;
+    QString m_fontFamily;
 };
 
 #endif // THEMEMANAGER_H