Qt:QFileDialog打开文件对话框记住上次打开路径

调用QFileDialog打开文件对话框时，第二次打开文件对话框直接定位到上次打开文件位置

  QSettings setting("./Setting.ini", QSettings::IniFormat);
    QString lastPath = setting.value("LastFilePath").toString();
    QString openFile = QFileDialog::getOpenFileName(this,"选择需要打开的文件", lastPath,
                                                    "文件类型(*.ppt;*.pptx;*.Jpg;*.jpeg;*.png;*.bmp;*.gif;*.Png;*.txt)");
    if (QFile::exists(openFile))
    {
        QFile file(openFile);
        file.setPermissions(QFile::ReadOther | QFile::WriteOther | QFile::ExeOther);
    }