gistfile1.txt

Q_GLOBAL_STATIC(QVariantMap, settingsCache);
AgentSettings::AgentSettings()
    : QSettings(/* detos.json using JSONSettings */)
{
}

QVariant AgentSettings::value(const QString &key, const QVariant &default)
{
    if (settingsCache().contains(key))
        return settingsCache().value(key);
    QSettings::value(key, default)
}

void AgentSettings::setValue(const QString &key, const QVariant &value)
{
    settingsCache().insert(key, value);
}