Add fonts to QPlatformTheme.

- Remove QPlatformFontDatabase::defaultFonts() returning
  a hash containing widget name ->font and the Windows
  implementation.
- Add enumeration and font accessor to QPlatformTheme. The value
  returned for the enumeration value overwrites the default font
  of the font database.
- Implement for Windows, Mac and KDE.
- Add more Windows palettes.

Task-number: QTBUG-23686

Change-Id: I8a2abdfd216df23daa7c9630c54264cdf61295db
Reviewed-by: Morten Johan Sørvig <morten.sorvig@nokia.com>

2 files changed, 64 insertions, 10 deletions

diff --git a/src/platformsupport/themes/genericunix/qgenericunixthemes.cpp b/src/platformsupport/themes/genericunix/qgenericunixthemes.cpp
index 257fe9156f..602dd6264a 100644
--- a/src/platformsupport/themes/genericunix/qgenericunixthemes.cpp
+++ b/src/platformsupport/themes/genericunix/qgenericunixthemes.cpp
@@ -43,6 +43,7 @@
 #include "../../services/genericunix/qgenericunixservices_p.h"
 
 #include <QtGui/QPalette>
+#include <QtGui/QFont>
 #include <QtGui/QGuiApplication>
 #include <QtCore/QDir>
 #include <QtCore/QFileInfo>
@@ -54,6 +55,20 @@
 
 QT_BEGIN_NAMESPACE
 
+ResourceHelper::ResourceHelper()
+{
+    qFill(palettes, palettes + QPlatformTheme::NPalettes, static_cast<QPalette *>(0));
+    qFill(fonts, fonts + QPlatformTheme::NFonts, static_cast<QFont *>(0));
+}
+
+void ResourceHelper::clear()
+{
+    qDeleteAll(palettes, palettes + QPlatformTheme::NPalettes);
+    qDeleteAll(fonts, fonts + QPlatformTheme::NFonts);
+    qFill(palettes, palettes + QPlatformTheme::NPalettes, static_cast<QPalette *>(0));
+    qFill(fonts, fonts + QPlatformTheme::NFonts, static_cast<QFont *>(0));
+}
+
 /*!
     \class QGenericX11ThemeQKdeTheme
     \brief QGenericX11Theme is a generic theme implementation for X11.
@@ -148,19 +163,40 @@ QKdeTheme::QKdeTheme(const QString &kdeHome, int kdeVersion) :
     m_kdeHome(kdeHome), m_kdeVersion(kdeVersion),
     m_toolButtonStyle(Qt::ToolButtonTextBesideIcon), m_toolBarIconSize(0)
 {
-    qFill(m_palettes, m_palettes + NPalettes, static_cast<QPalette *>(0));
     refresh();
 }
 
-void QKdeTheme::clearPalettes()
+static inline QFont *readKdeFontSetting(const QSettings &settings, const QString &key)
 {
-     qDeleteAll(m_palettes, m_palettes + NPalettes);
-     qFill(m_palettes, m_palettes + NPalettes, static_cast<QPalette *>(0));
+    const QVariant fontValue = settings.value(key);
+    if (fontValue.isValid()) {
+        // Read font value: Might be a QStringList as KDE stores fonts without quotes.
+        // Also retrieve the family for the constructor since we cannot use the
+        // default constructor of QFont, which accesses QGuiApplication::systemFont()
+        // causing recursion.
+        QString fontDescription;
+        QString fontFamily;
+        if (fontValue.type() == QVariant::StringList) {
+            const QStringList list = fontValue.toStringList();
+            if (!list.isEmpty()) {
+                fontFamily = list.first();
+                fontDescription = list.join(QStringLiteral(","));
+            }
+        } else {
+            fontDescription = fontFamily = fontValue.toString();
+        }
+        if (!fontDescription.isEmpty()) {
+            QFont font(fontFamily);
+            if (font.fromString(fontDescription))
+                return new QFont(font);
+        }
+    }
+    return 0;
 }
 
 void QKdeTheme::refresh()
 {
-    clearPalettes();
+    m_resources.clear();
 
     m_toolButtonStyle = Qt::ToolButtonTextBesideIcon;
     m_toolBarIconSize = 0;
@@ -177,7 +213,7 @@ void QKdeTheme::refresh()
 
     QPalette systemPalette;
     if (readKdeSystemPalette(kdeSettings, &systemPalette))
-        m_palettes[SystemPalette] = new QPalette(systemPalette);
+        m_resources.palettes[SystemPalette] = new QPalette(systemPalette);
     //## TODO tooltip color
 
     const QVariant styleValue = kdeSettings.value(QStringLiteral("widgetStyle"));
@@ -205,6 +241,9 @@ void QKdeTheme::refresh()
         else if (toolBarStyle == QStringLiteral("TextUnderIcon"))
             m_toolButtonStyle = Qt::ToolButtonTextUnderIcon;
     }
+
+    // Read system font, ignore 'fixed' 'smallestReadableFont'
+    m_resources.fonts[SystemFont] = readKdeFontSetting(kdeSettings, QStringLiteral("font"));
 }
 
 QString QKdeTheme::globalSettingsFile() const
diff --git a/src/platformsupport/themes/genericunix/qgenericunixthemes_p.h b/src/platformsupport/themes/genericunix/qgenericunixthemes_p.h
index 12937a205f..a9db29e8cd 100644
--- a/src/platformsupport/themes/genericunix/qgenericunixthemes_p.h
+++ b/src/platformsupport/themes/genericunix/qgenericunixthemes_p.h
@@ -50,6 +50,18 @@ QT_BEGIN_HEADER
 
 QT_BEGIN_NAMESPACE
 
+class ResourceHelper
+{
+public:
+    ResourceHelper();
+    ~ResourceHelper() { clear(); }
+
+    void clear();
+
+    QPalette *palettes[QPlatformTheme::NPalettes];
+    QFont *fonts[QPlatformTheme::NFonts];
+};
+
 class QGenericUnixTheme : public QPlatformTheme
 {
 public:
@@ -66,21 +78,24 @@ class QKdeTheme : public QPlatformTheme
 {
     QKdeTheme(const QString &kdeHome, int kdeVersion);
 public:
-    ~QKdeTheme() { clearPalettes(); }
 
     static QPlatformTheme *createKdeTheme();
     virtual QVariant themeHint(ThemeHint hint) const;
+
     virtual const QPalette *palette(Palette type = SystemPalette) const
-        { return m_palettes[type]; }
+        { return m_resources.palettes[type]; }
+
+    virtual const QFont *font(Font type) const
+        { return m_resources.fonts[type]; }
 
 private:
     QString globalSettingsFile() const;
-    void clearPalettes();
     void refresh();
 
     const QString m_kdeHome;
     const int m_kdeVersion;
-    QPalette *m_palettes[NPalettes];
+
+    ResourceHelper m_resources;
     QString m_iconThemeName;
     QString m_iconFallbackThemeName;
     QStringList m_styleNames;