Settings class converted to singleton pattern.

CMakeLists.txt

@@ -174,6 +174,7 @@ set(APP_HEADERS
   # GUI headers.
   src/gui/formmain.h
   src/gui/systemtrayicon.cpp
+  src/gui/themefactory.cpp
 
   # CORE headers.
 )

src/core/settings.cpp

@@ -26,7 +26,16 @@
 #include "core/defs.h"
 
 
-QPointer<QSettings> Settings::s_instance;
+QPointer<Settings> Settings::s_instance;
+
+Settings::Settings(const QString &file_name, Format format, QObject *parent)
+  : QSettings(file_name, format, parent) {
+}
+
+Settings::~Settings() {
+  checkSettings();
+  qDebug("Deleting Settings instance.");
+}
 
 QSettings::Status Settings::checkSettings() {
   qDebug("Syncing settings.");
@@ -35,28 +44,24 @@ QSettings::Status Settings::checkSettings() {
   return s_instance->status();
 }
 
-QVariant Settings::value(const QString &section,
-                         const QString &key,
-                         const QVariant &default_value) {
+Settings &Settings::getInstance() {
   if (s_instance.isNull()) {
     setupSettings();
   }
-  return s_instance->value(QString("%1/%2").arg(section, key), default_value);
+
+  return *s_instance;
+}
+
+QVariant Settings::value(const QString &section,
+                         const QString &key,
+                         const QVariant &default_value) {
+  return QSettings::value(QString("%1/%2").arg(section, key), default_value);
 }
 
 void Settings::setValue(const QString &section,
                         const QString &key,
                         const QVariant &value) {
-  if (s_instance.isNull()) {
-    setupSettings();
-  }
-  s_instance->setValue(QString("%1/%2").arg(section, key), value);
-}
-
-void Settings::deleteSettings() {
-  checkSettings();
-  qDebug("Deleting global settings.");
-  delete s_instance.data();
+  QSettings::setValue(QString("%1/%2").arg(section, key), value);
 }
 
 QSettings::Status Settings::setupSettings() {
@@ -70,15 +75,15 @@ QSettings::Status Settings::setupSettings() {
                      APP_CFG_PATH;
 
   if (QFile(app_path).exists()) {
-    s_instance = new QSettings(app_path, QSettings::IniFormat);
+    s_instance = new Settings(app_path, QSettings::IniFormat, qApp);
     qDebug("Initializing settings in %s.",
            qPrintable(QDir::toNativeSeparators(app_path)));
   }
   else {
-    s_instance = new QSettings(home_path, QSettings::IniFormat);
+    s_instance = new Settings(home_path, QSettings::IniFormat, qApp);
     qDebug("Initializing settings in %s.",
            qPrintable(QDir::toNativeSeparators(home_path)));
   }
 
-  return checkSettings();
+  return (*s_instance).checkSettings();
 }

src/core/settings.h

@@ -4,27 +4,31 @@
 #include <QSettings>
 
 
-class Settings {
+class Settings : public QSettings {
   private:
     // We use QPointer instead of QScopedPointer
     // because of late s_instance usage in QApplication::aboutToQuit() listeners.
-    static QPointer<QSettings> s_instance;
+    static QPointer<Settings> s_instance;
 
   public:
+    // Singleton getter.
+    static Settings &getInstance();
+
+    // Constructor and destructor.
+    Settings(const QString & file_name, Format format, QObject * parent = 0);
+    ~Settings();
+
     // Getter/setter for settings values.
-    static QVariant value(const QString &section,
-                          const QString &key,
-                          const QVariant &default_value = QVariant());
+    QVariant value(const QString &section,
+                   const QString &key,
+                   const QVariant &default_value = QVariant());
 
-    static void setValue(const QString &section,
-                         const QString &key,
-                         const QVariant &value);
-
-    // It's better to cleanup settings manually via this function.
-    static void deleteSettings();
+    void setValue(const QString &section,
+                  const QString &key,
+                  const QVariant &value);
 
     // Synchronises settings.
-    static QSettings::Status checkSettings();
+    QSettings::Status checkSettings();
 
   protected:
     // Creates settings file in correct location.

src/gui/formmain.cpp

@@ -19,10 +19,19 @@ void FormMain::processExecutionMessage(const QString &message) {
          qPrintable(message));
 }
 
+void FormMain::quit() {
+  qDebug("Quitting the application.");
+  qApp->quit();
+}
+
 void FormMain::cleanupResources() {
-  Settings::deleteSettings();
+  qDebug("Cleaning up resources before the application exits.");
 }
 
 void FormMain::createConnections() {
+  // Menu "File" connections.
+  connect(m_ui->m_actionQuit, &QAction::triggered, this, &FormMain::quit);
+
+  // General connections.
   connect(qApp, &QCoreApplication::aboutToQuit, this, &FormMain::cleanupResources);
 }

src/gui/formmain.h

@@ -18,6 +18,7 @@ class FormMain : public QMainWindow {
 
   public slots:
     void processExecutionMessage(const QString &message);
+    void quit();
 
   protected slots:
     void cleanupResources();

src/gui/formmain.ui

@@ -14,17 +14,54 @@
    <string>MainWindow</string>
   </property>
   <widget class="QWidget" name="centralwidget"/>
-  <widget class="QMenuBar" name="menubar">
+  <widget class="QMenuBar" name="m_menuBar">
    <property name="geometry">
     <rect>
      <x>0</x>
      <y>0</y>
      <width>800</width>
-     <height>21</height>
+     <height>19</height>
     </rect>
    </property>
+   <widget class="QMenu" name="m_menuFile">
+    <property name="title">
+     <string>&amp;File</string>
+    </property>
+    <addaction name="m_actionImport"/>
+    <addaction name="m_actionExport"/>
+    <addaction name="separator"/>
+    <addaction name="m_actionQuit"/>
+   </widget>
+   <widget class="QMenu" name="m_menuHelp">
+    <property name="title">
+     <string>&amp;Help</string>
+    </property>
+   </widget>
+   <widget class="QMenu" name="menu_View">
+    <property name="title">
+     <string>&amp;View</string>
+    </property>
+   </widget>
+   <addaction name="m_menuFile"/>
+   <addaction name="menu_View"/>
+   <addaction name="m_menuHelp"/>
   </widget>
   <widget class="QStatusBar" name="statusbar"/>
+  <action name="m_actionImport">
+   <property name="text">
+    <string>&amp;Import</string>
+   </property>
+  </action>
+  <action name="m_actionExport">
+   <property name="text">
+    <string>E&amp;xport</string>
+   </property>
+  </action>
+  <action name="m_actionQuit">
+   <property name="text">
+    <string>&amp;Quit</string>
+   </property>
+  </action>
  </widget>
  <resources/>
  <connections/>

src/gui/themefactory.cpp

@@ -0,0 +1,5 @@
+#include "themefactory.h"
+
+
+ThemeFactory::ThemeFactory() {
+}

src/gui/themefactory.h

@@ -0,0 +1,10 @@
+#ifndef THEMEFACTORY_H
+#define THEMEFACTORY_H
+
+
+class ThemeFactory {
+  private:
+    ThemeFactory();
+};
+
+#endif // THEMEFACTORY_H

src/main.cpp

@@ -63,9 +63,9 @@ int main(int argc, char *argv[]) {
 
   window.show();
 
-  if (Settings::value(APP_CFG_GEN, "first_start", true).toBool()) {
+  if (Settings::getInstance().value(APP_CFG_GEN, "first_start", true).toBool()) {
     // TODO: Open initial "Welcome" dialog here.
-    Settings::setValue(APP_CFG_GEN, "first_start", false);
+    Settings::getInstance().setValue(APP_CFG_GEN, "first_start", false);
   }