autosaver.cpp Example File

webenginewidgets/demobrowser/autosaver.cpp
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#include "autosaver.h" #include <QtCore/QDir> #include <QtCore/QCoreApplication> #include <QtCore/QMetaObject> #include <QtDebug> #define AUTOSAVE_IN 1000 * 3 // seconds #define MAXWAIT 1000 * 15 // seconds AutoSaver::AutoSaver(QObject *parent) : QObject(parent) { Q_ASSERT(parent); } AutoSaver::~AutoSaver() { if (m_timer.isActive()) qWarning() << "AutoSaver: still active when destroyed, changes not saved."; } void AutoSaver::changeOccurred() { if (m_firstChange.isNull()) m_firstChange.start(); if (m_firstChange.elapsed() > MAXWAIT) { saveIfNeccessary(); } else { m_timer.start(AUTOSAVE_IN, this); } } void AutoSaver::timerEvent(QTimerEvent *event) { if (event->timerId() == m_timer.timerId()) { saveIfNeccessary(); } else { QObject::timerEvent(event); } } void AutoSaver::saveIfNeccessary() { if (!m_timer.isActive()) return; m_timer.stop(); m_firstChange = QTime(); if (!QMetaObject::invokeMethod(parent(), "save", Qt::DirectConnection)) { qWarning() << "AutoSaver: error invoking slot save() on parent"; } }