Load fonts using QML FontLoader instead of adding to font db

This should fix the case for loading fonts via URL in the wasm case.

CMakeLists.txt

@@ -225,6 +225,7 @@ set (VENUS_QML_MODULE_SOURCES
     components/ToastNotification.qml
     components/Utils.js
     components/ValueRange.qml
+    components/VenusFontLoader.qml
     components/VerticalGauge.qml
     components/ViewGradient.qml
     components/ClassAndVrmInstance.qml

Global.qml

@@ -18,6 +18,7 @@ QtObject {
 	property VeQItemTableModel dataServiceModel: null
 	property var firmwareUpdate
 
+	property var fontLoader
 	property var inputPanel
 	property var dialogLayer
 	property var notificationLayer

Main.qml

@@ -182,6 +182,12 @@ Window {
 				}
 			}
 		}
+
+		VenusFontLoader {
+			id: fontLoader
+
+			Component.onCompleted: Global.fontLoader = fontLoader
+		}
 	}
 
 	FrameRateVisualizer {}

components/ControlCard.qml

@@ -29,7 +29,7 @@ Rectangle {
 		display: C.AbstractButton.TextBesideIcon
 		icon.color: Theme.color_font_primary
 
-		font.family: Language.fontFamily
+		font.family: Global.fontLoader.name
 		font.pixelSize: Theme.font_size_body1
 		color: Theme.color_font_primary
 	}

components/VenusFontLoader.qml

@@ -0,0 +1,11 @@
+/*
+** Copyright (C) 2023 Victron Energy B.V.
+** See LICENSE.txt for license information.
+*/
+
+import QtQuick
+import Victron.VenusOS
+
+FontLoader {
+	source: Language.fontFileUrl
+}

components/controls/Button.qml

@@ -36,7 +36,7 @@ CT.Button {
 
 	icon.color: root.color
 
-	font.family: Language.fontFamily
+	font.family: Global.fontLoader.name
 	font.pixelSize: Theme.font_size_body1
 	flat: true
 

components/controls/Label.qml

@@ -9,6 +9,6 @@ import Victron.VenusOS
 
 C.Label {
 	color: Theme.color_font_primary
-	font.family: Language.fontFamily
+	font.family: Global.fontLoader.name
 	font.pixelSize: Theme.font_size_body1
 }

components/controls/TextField.qml

@@ -10,7 +10,7 @@ import Victron.VenusOS
 CT.TextField {
 	id: root
 
-	font.family: Language.fontFamily
+	font.family: Global.fontLoader.name
 	font.pixelSize: Theme.font_size_body2
 
 	leftPadding: Theme.geometry_textField_horizontalMargin

components/listitems/ListRadioButtonGroup.qml

@@ -101,8 +101,8 @@ ListNavigationItem {
 						  ? !modelData.readOnly
 						  : !model.readOnly)
 					primaryLabel.font.family: Array.isArray(root.optionModel)
-						  ? modelData.fontFamily || Language.fontFamily
-						  : model.fontFamily || Language.fontFamily
+						  ? modelData.fontFamily || Global.fontLoader.name
+						  : model.fontFamily || Global.fontLoader.name
 
 					visible: (userHasWriteAccess && enabled) || checked
 					checked: root.currentIndex === model.index

pages/settings/PageSettingsDisplay.qml

@@ -122,6 +122,11 @@ Page {
 					model: languageModel
 					delegate: FontLoader {
 						source: model.fontFileUrl
+						onStatusChanged: {
+							if (status === FontLoader.Ready) {
+								languageModel.setFontFamily(source, name)
+							}
+						}
 					}
 				}
 

src/language.cpp

@@ -17,79 +17,31 @@ using namespace Victron::VenusOS;
 
 namespace {
 
-QString defaultFontFileName()
+QUrl fontUrlForLanguage(QLocale::Language language)
 {
-	return QStringLiteral(":/fonts/MuseoSans-500.otf");
-}
-
-QString fontFileNameForLanguage(QLocale::Language language)
-{
-	QString fileName;
-
 	static const QHash<QLocale::Language, QString> fontFileNames = {
 		{ QLocale::Arabic, QStringLiteral("DejaVuSans.ttf") },
 		{ QLocale::Chinese, QStringLiteral("DroidSansFallback.ttf") },
 		{ QLocale::Thai, QStringLiteral("NotoSansThai.ttf") },
 	};
 
 #if defined(VENUS_WEBASSEMBLY_BUILD)
-	// On wasm, the root dir contains symlinks to the required font files.
-	fileName = fontFileNames.value(language);
+	// On wasm, the server contains symlinks to the required font files in the root dir.
+	QString fileName = fontFileNames.value(language);
 	if (!fileName.isEmpty()) {
-		fileName = "/" + fileName;
+		return QUrl("http://127.0.0.1/" + fileName);
 	}
 #elif not defined(VENUS_DESKTOP_BUILD)
 	// On device, look for the system-installed font files.
-	fileName = fontFileNames.value(language);
+	QString fileName = fontFileNames.value(language);
 	if (!fileName.isEmpty()) {
-		fileName = "/usr/lib/fonts/" + fileName;
+		return QUrl::fromLocalFile("/usr/lib/fonts/" + fileName);
 	}
-#else
-	// On other platforms, use the default font for all languages.
-	Q_UNUSED(language)
-	fileName = defaultFontFileName();
 #endif
 
-	return !fileName.isEmpty() && QFile::exists(fileName) ? fileName : defaultFontFileName();
-}
-
-QUrl filePathToUrl(const QString &path)
-{
-	if (path.isEmpty()) {
-		return QUrl();
-	}
-
-	if (path.startsWith(':')) {
-		// Convert to QML-friendly "qrc:/" resource path.
-		return QUrl(QStringLiteral("qrc%1").arg(path));
-	}
-
-	return QUrl::fromLocalFile(path);
-}
-
-QString fontFamilyForLanguage(QLocale::Language language)
-{
-	static QHash<QString, int> fontIds;
-
-	const QString fontFileName = fontFileNameForLanguage(language);
-	if (!fontIds.contains(fontFileName)) {
-		fontIds.insert(fontFileName, QFontDatabase::addApplicationFont(fontFileName));
-	}
-
-	int fontId = fontIds.value(fontFileName, -1);
-	if (fontId < 0) {
-		qWarning() << "Fall back to default font, cannot load" << fontFileName << "for locale" << QLocale(language).name();
-		if (!fontIds.contains(defaultFontFileName())) {
-			fontIds.insert(fontFileName, QFontDatabase::addApplicationFont(defaultFontFileName()));
-		}
-		fontId = fontIds.value(defaultFontFileName(), -1);
-		if (fontId < 0) {
-			qWarning() << "Unable to fall back to default font!";
-			return QString();
-		}
-	}
-
-	return QFontDatabase::applicationFontFamilies(fontId).value(0);
+	// Use the default font on other platforms, or if the default font supports this language.
+	static const QUrl defaultFontUrl = QUrl("qrc:/fonts/MuseoSans-500.otf");
+	return defaultFontUrl;
 }
 
 }
@@ -168,6 +120,18 @@ int LanguageModel::languageAt(int index) const
 	return m_languages.at(index).language;
 }
 
+void LanguageModel::setFontFamily(const QUrl &fontUrl, const QString &fontFamily)
+{
+	for (int i = 0; i < m_languages.count(); ++i) {
+		if (m_languages.at(i).fontFileUrl == fontUrl) {
+			m_languages[i].fontFamily = fontFamily;
+			static const QList<int> roles = { FontFamilyRole };
+			emit dataChanged(createIndex(i, 0), createIndex(i, 0), roles);
+			break;
+		}
+	}
+}
+
 int LanguageModel::rowCount(const QModelIndex &) const
 {
 	return static_cast<int>(m_languages.count());
@@ -195,7 +159,7 @@ QVariant LanguageModel::data(const QModelIndex &index, int role) const
 
 void LanguageModel::addLanguage(const QString &name, const QString &code, const QLocale::Language &language)
 {
-	m_languages.append({name, code, filePathToUrl(fontFileNameForLanguage(language)), fontFamilyForLanguage(language), language });
+	m_languages.append({name, code, fontUrlForLanguage(language), QString(), language });
 }
 
 QHash<int, QByteArray> LanguageModel::roleNames() const
@@ -244,7 +208,6 @@ void Language::setCurrentLanguage(QLocale::Language language)
 	if (language != m_currentLanguage && installTranslatorForLanguage(language)) {
 		emit currentLanguageChanged();
 		emit fontFileUrlChanged();
-		emit fontFamilyChanged();
 	}
 }
 
@@ -253,11 +216,6 @@ QUrl Language::fontFileUrl() const
 	return m_fontFileUrl;
 }
 
-QString Language::fontFamily() const
-{
-	return m_fontFamily;
-}
-
 void Language::setCurrentLanguageCode(const QString &code)
 {
 	const QLocale::Language lang = QLocale::codeToLanguage(code);
@@ -308,8 +266,7 @@ bool Language::installTranslatorForLanguage(QLocale::Language language)
 	}
 
 	m_currentLanguage = language;
-	m_fontFileUrl = filePathToUrl(fontFileNameForLanguage(language));
-	m_fontFamily = fontFamilyForLanguage(language);
+	m_fontFileUrl = fontUrlForLanguage(language);
 
 	return true;
 }

src/language.h

@@ -46,6 +46,7 @@ class LanguageModel : public QAbstractListModel
 	QString currentDisplayText() const;
 
 	Q_INVOKABLE int languageAt(int index) const;
+	Q_INVOKABLE void setFontFamily(const QUrl &fontUrl, const QString &fontFamily);
 
 	int rowCount(const QModelIndex &parent = QModelIndex()) const override;
 	QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
@@ -82,7 +83,6 @@ class Language : public QObject
 	QML_SINGLETON
 	Q_PROPERTY(QLocale::Language current READ getCurrentLanguage WRITE setCurrentLanguage NOTIFY currentLanguageChanged FINAL)
 	Q_PROPERTY(QUrl fontFileUrl READ fontFileUrl NOTIFY fontFileUrlChanged FINAL)
-	Q_PROPERTY(QString fontFamily READ fontFamily NOTIFY fontFamilyChanged FINAL)
 
 public:
 	static Language* create(QQmlEngine *engine = nullptr, QJSEngine *jsEngine = nullptr);
@@ -102,21 +102,18 @@ class Language : public QObject
 	void setCurrentLanguage(QLocale::Language language);
 
 	QUrl fontFileUrl() const;
-	QString fontFamily() const;
 
 Q_SIGNALS:
 	void currentLanguageChanged();
 	void fontFileUrlChanged();
-	void fontFamilyChanged();
 
 private:
 	explicit Language(QQmlEngine* engine);
 	bool installTranslatorForLanguage(QLocale::Language language);
 
-	QUrl m_fontFileUrl;
-	QString m_fontFamily;
 	QLocale::Language m_currentLanguage = QLocale::AnyLanguage;
 	QHash<QLocale::Language, QTranslator*> m_loadedTranslators;
+	QUrl m_fontFileUrl;
 };
 
 } /* VenusOS */