Add dark UI theme and custom theme support

src/app/resources/zeal.qrc

@@ -244,5 +244,6 @@
         <file>icons/logo/128x128.png</file>
         <file>icons/logo/icon.png</file>
         <file>icons/logo/icon@2x.png</file>
+        <file>css/darkorange.stylesheet</file>
     </qresource>
 </RCC>

src/libs/core/settings.cpp

@@ -51,6 +51,7 @@ Settings::Settings(QObject *parent) :
     QObject(parent)
 {
     qRegisterMetaTypeStreamOperators<ExternalLinkPolicy>("ExternalLinkPolicy");
+    qRegisterMetaTypeStreamOperators<UiStyle>("UiStyle");
 
     // Enable local storage due to https://github.com/zealdocs/zeal/issues/872.
     QWebSettings *webSettings = QWebSettings::globalSettings();
@@ -135,6 +136,9 @@ void Settings::load()
     darkModeEnabled = settings->value(QStringLiteral("dark_mode"), false).toBool();
     highlightOnNavigateEnabled = settings->value(QStringLiteral("highlight_on_navigate"), true).toBool();
     customCssFile = settings->value(QStringLiteral("custom_css_file")).toString();
+    uiStyle = settings->value(QStringLiteral("ui_style"),
+                                         QVariant::fromValue(UiStyle::SystemDefault)).value<UiStyle>();
+    customUiCssFile = settings->value(QStringLiteral("custom_ui_css_file")).toString();
     externalLinkPolicy = settings->value(QStringLiteral("external_link_policy"),
                                          QVariant::fromValue(ExternalLinkPolicy::Ask)).value<ExternalLinkPolicy>();
     isSmoothScrollingEnabled = settings->value(QStringLiteral("smooth_scrolling"), false).toBool();
@@ -224,6 +228,8 @@ void Settings::save()
     settings->setValue(QStringLiteral("dark_mode"), darkModeEnabled);
     settings->setValue(QStringLiteral("highlight_on_navigate"), highlightOnNavigateEnabled);
     settings->setValue(QStringLiteral("custom_css_file"), customCssFile);
+    settings->setValue(QStringLiteral("ui_style"), QVariant::fromValue(uiStyle));
+    settings->setValue(QStringLiteral("custom_ui_css_file"), customUiCssFile);
     settings->setValue(QStringLiteral("external_link_policy"), QVariant::fromValue(externalLinkPolicy));
     settings->setValue(QStringLiteral("smooth_scrolling"), isSmoothScrollingEnabled);
     settings->endGroup();
@@ -347,3 +353,17 @@ QDataStream &operator>>(QDataStream &in, Settings::ExternalLinkPolicy &policy)
     policy = static_cast<Settings::ExternalLinkPolicy>(value);
     return in;
 }
+
+QDataStream &operator<<(QDataStream &out, Settings::UiStyle uiStyle)
+{
+    out << static_cast<std::underlying_type<Settings::UiStyle>::type>(uiStyle);
+    return out;
+}
+
+QDataStream &operator>>(QDataStream &in, Settings::UiStyle &uiStyle)
+{
+    std::underlying_type<Settings::UiStyle>::type value;
+    in >> value;
+    uiStyle = static_cast<Settings::UiStyle>(value);
+    return in;
+}

src/libs/core/settings.h

@@ -83,6 +83,15 @@ class Settings final : public QObject
     QString customCssFile;
     bool isSmoothScrollingEnabled;
 
+    enum class UiStyle {
+        SystemDefault,
+        Dark,
+        CustomCssFile
+    };
+    Q_ENUM(UiStyle)
+    UiStyle uiStyle = UiStyle::SystemDefault;
+    QString customUiCssFile;
+
     // Network
     enum ProxyType : unsigned int {
         None = 0,

src/libs/ui/mainwindow.cpp

@@ -516,6 +516,24 @@ void MainWindow::keyPressEvent(QKeyEvent *keyEvent)
     }
 }
 
+namespace
+{
+    void addFileContent(QByteArray& destinationArray, const QString& filename)
+    {
+        if (filename.isEmpty()) {
+            return;
+        }
+        if (QFileInfo::exists(filename)) {
+            QFile file(filename);
+            if (file.open(QIODevice::ReadOnly)) {
+                destinationArray += file.readAll();
+            }
+        } else {
+            qWarning("File does not exists: %s", filename.toUtf8().data());
+        }
+    }
+}
+
 void MainWindow::applySettings()
 {
     m_globalShortcut->setShortcut(m_settings->showShortcut);
@@ -525,27 +543,33 @@ void MainWindow::applySettings()
     else
         removeTrayIcon();
 
+    // UI style
+    QByteArray uiCsssContent;
+    switch (m_settings->uiStyle) {
+    case Core::Settings::UiStyle::SystemDefault:
+        // system style = no css content
+        break;
+    case Core::Settings::UiStyle::Dark:
+        addFileContent(uiCsssContent, ":/css/darkorange.stylesheet");
+        break;
+    case Core::Settings::UiStyle::CustomCssFile:
+        addFileContent(uiCsssContent, m_settings->customUiCssFile);
+        break;
+    }
+    qApp->setStyleSheet(QString::fromUtf8(uiCsssContent));
+
     // Content
     QByteArray ba = QByteArrayLiteral("body { background-color: white; }");
     if (m_settings->darkModeEnabled) {
-        QScopedPointer<QFile> file(new QFile(DarkModeCssUrl));
-        if (file->open(QIODevice::ReadOnly)) {
-            ba += file->readAll();
-        }
+        addFileContent(ba, DarkModeCssUrl);
     }
 
     if (m_settings->highlightOnNavigateEnabled) {
-        QScopedPointer<QFile> file(new QFile(HighlightOnNavigateCssUrl));
-        if (file->open(QIODevice::ReadOnly)) {
-            ba += file->readAll();
-        }
+        addFileContent(ba, HighlightOnNavigateCssUrl);
     }
 
     if (QFileInfo::exists(m_settings->customCssFile)) {
-        QScopedPointer<QFile> file(new QFile(m_settings->customCssFile));
-        if (file->open(QIODevice::ReadOnly)) {
-            ba += file->readAll();
-        }
+        addFileContent(ba, m_settings->customCssFile);
     }
 
     const QString cssUrl = QLatin1String("data:text/css;charset=utf-8;base64,") + ba.toBase64();

src/libs/ui/searchitemdelegate.cpp

@@ -123,14 +123,19 @@ void SearchItemDelegate::paint(QPainter *painter, const QStyleOptionViewItem &op
     const QString elidedText = fm.elidedText(opt.text, opt.textElideMode, textRect.width());
 
     if (!m_highlight.isEmpty()) {
+        QColor highlightColor = QColor::fromRgb(255, 255, 100);
+        if(painter->pen().color().toHsv().value() > 127)
+            highlightColor = QColor::fromRgb(100, 100, 0);;
+
+        if(opt.state & (QStyle::State_Selected | QStyle::State_HasFocus))
+            highlightColor.setAlpha(20);
+        else
+            highlightColor.setAlpha(120);
+
         painter->save();
         painter->setRenderHint(QPainter::Antialiasing);
         painter->setPen(QColor::fromRgb(255, 253, 0));
 
-        const QColor highlightColor
-                = (opt.state & (QStyle::State_Selected | QStyle::State_HasFocus))
-                ? QColor::fromRgb(255, 255, 100, 20) : QColor::fromRgb(255, 255, 100, 120);
-
         for (int i = 0;;) {
             const int matchIndex = opt.text.indexOf(m_highlight, i, Qt::CaseInsensitive);
             if (matchIndex == -1 || matchIndex >= elidedText.length() - 1)

src/libs/ui/settingsdialog.cpp

@@ -141,6 +141,17 @@ void SettingsDialog::chooseCustomCssFile()
     ui->customCssFileEdit->setText(QDir::toNativeSeparators(file));
 }
 
+void SettingsDialog::chooseCustomUiCssFile()
+{
+    const QString file = QFileDialog::getOpenFileName(this, tr("Choose UI CSS File"),
+                                                      ui->customCssFileEdit->text(),
+                                                      tr("CSS Files (*.css);;All Files (*.*)"));
+    if (file.isEmpty())
+        return;
+
+    ui->customUiCssFileEdit->setText(QDir::toNativeSeparators(file));
+}
+
 void SettingsDialog::chooseDocsetStoragePath()
 {
     QString path = QFileDialog::getExistingDirectory(this, tr("Open Directory"),
@@ -201,6 +212,19 @@ void SettingsDialog::loadSettings()
     ui->highlightOnNavigateCheckBox->setChecked(settings->highlightOnNavigateEnabled);
     ui->customCssFileEdit->setText(QDir::toNativeSeparators(settings->customCssFile));
 
+    switch (settings->uiStyle) {
+    case Core::Settings::UiStyle::SystemDefault:
+        ui->radioUiStyleSystemDefault->setChecked(true);
+        break;
+    case Core::Settings::UiStyle::Dark:
+        ui->radioUiStyleDark->setChecked(true);
+        break;
+    case Core::Settings::UiStyle::CustomCssFile:
+        ui->radioUiStyleCustomCssFile->setChecked(true);
+        break;
+    }
+    ui->customUiCssFileEdit->setText(QDir::toNativeSeparators(settings->customUiCssFile));
+
     switch (settings->externalLinkPolicy) {
     case Core::Settings::ExternalLinkPolicy::Ask:
         ui->radioExternalLinkAsk->setChecked(true);
@@ -276,6 +300,15 @@ void SettingsDialog::saveSettings()
     settings->highlightOnNavigateEnabled = ui->highlightOnNavigateCheckBox->isChecked();
     settings->customCssFile = QDir::fromNativeSeparators(ui->customCssFileEdit->text());
 
+    if (ui->radioUiStyleSystemDefault->isChecked()) {
+        settings->uiStyle = Core::Settings::UiStyle::SystemDefault;
+    } else if (ui->radioUiStyleDark->isChecked()) {
+        settings->uiStyle = Core::Settings::UiStyle::Dark;
+    } else if (ui->radioUiStyleCustomCssFile->isChecked()) {
+        settings->uiStyle = Core::Settings::UiStyle::CustomCssFile;
+    }
+    settings->customUiCssFile = QDir::fromNativeSeparators(ui->customUiCssFileEdit->text());
+
     if (ui->radioExternalLinkAsk->isChecked()) {
         settings->externalLinkPolicy = Core::Settings::ExternalLinkPolicy::Ask;
     } else if (ui->radioExternalLinkOpen->isChecked()) {

src/libs/ui/settingsdialog.h

@@ -42,6 +42,7 @@ class SettingsDialog : public QDialog
 
 private slots:
     void chooseCustomCssFile();
+    void chooseCustomUiCssFile();
     void chooseDocsetStoragePath();
 
 private: