+class COMMON_EXPORT Settings
+{
+public:
+ enum Mode { Default, Custom };
+
+public:
+ //! Call the given slot on change of the given key
+ virtual void notify(const QString &key, QObject *receiver, const char *slot);
+
+ //! Sets up notification and calls the given slot to set the initial value
+ void initAndNotify(const QString &key, QObject *receiver, const char *slot, const QVariant &defaultValue = QVariant());
+
+ /**
+ * Get the major configuration version
+ *
+ * This indicates the backwards/forwards incompatible version of configuration.
+ *
+ * @return Major configuration version (the X in XX.YY)
+ */
+ virtual uint version();
+
+ /**
+ * Get the minor configuration version
+ *
+ * This indicates the backwards/forwards compatible version of configuration.
+ *
+ * @see Settings::setVersionMinor()
+ * @return Minor configuration version (the Y in XX.YY)
+ */
+ virtual uint versionMinor();
+
+ /**
+ * Set the minor configuration version
+ *
+ * When making backwards/forwards compatible changes, call this with the new version number.
+ * This does not implement any upgrade logic; implement that when checking Settings::version(),
+ * e.g. in Core::Core() and QtUiApplication::init().
+ *
+ * @param[in] versionMinor New minor version number
+ */
+ virtual void setVersionMinor(const uint versionMinor);
+
+ /**
+ * Persist unsaved changes to permanent storage
+ *
+ * @return true if succeeded, false otherwise
+ */
+ bool sync();
+
+ /**
+ * Check if the configuration storage is writable.
+ *
+ * @return true if writable, false otherwise
+ */
+ bool isWritable();
+
+protected:
+ inline Settings(QString group_, QString appName_) : group(group_), appName(appName_) {}
+ inline virtual ~Settings() {}
+
+ inline void setGroup(const QString &group_) { group = group_; }
+
+ virtual QStringList allLocalKeys();
+ virtual QStringList localChildKeys(const QString &rootkey = QString());
+ virtual QStringList localChildGroups(const QString &rootkey = QString());
+
+ virtual void setLocalValue(const QString &key, const QVariant &data);
+ virtual QVariant localValue(const QString &key, const QVariant &def = QVariant());
+
+ /**
+ * Gets if a key exists in settings
+ *
+ * @param[in] key ID of local settings key
+ * @returns True if key exists in settings, otherwise false
+ */
+ virtual bool localKeyExists(const QString &key);
+
+ virtual void removeLocalKey(const QString &key);
+
+ QString group;
+ QString appName;
+
+private:
+ inline QSettings::Format format()
+ {
+#ifdef Q_OS_WIN
+ return QSettings::IniFormat;
+#else
+ return QSettings::NativeFormat;