QT恢复上一次窗口退出状态，代码

{

    QSettings settings("1321235", "123");

    QRect geom = this->rect();

    QPoint pos = settings.value("pos", QPoint(200, 200)).toPoint();

    QSize sz = settings.value("size", QSize(2 * geom.width() / 3, 2 * geom.height() / 3)).toSize();

    move(pos);

    resize(sz);

}

void MainWindow::writSetting()

{

    QSettings settings("1321235", "123");

    settings.setValue("pos", pos());

    settings.setValue("size", size());

}

void MainWindow::closeEvent(QCloseEvent* event)

{

    writSetting();

}

使用QSetting记录上次窗口退出大小位置，窗口关闭时执行writeSetting()函数，在界面构造函数里执行readSetting（）函数；