Qt 5.11 | Qt Quick Controls | Qt Quick Controls - File System Browser Example | main.cpp Example File

Qt 5.11.3 Reference Documentation

# main.cpp Example File

filesystembrowser/main.cpp

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      #include <QApplication>
      #include <QQmlApplicationEngine>
      #include <QtQml>
      #include <QFileSystemModel>
      #include <QDateTime>
      #include <QDesktopServices>
      #include <QUrl>

      static inline QString permissionString(const QFileInfo &fi)
      {
          const QFile::Permissions permissions = fi.permissions();
          QString result = QLatin1String("----------");
          if (fi.isSymLink())
              result[0] = QLatin1Char('l');
          else if (fi.isDir())
              result[0] = QLatin1Char('d');
          if (permissions & QFileDevice::ReadUser)
              result[1] = QLatin1Char('r');
          if (permissions & QFileDevice::WriteUser)
              result[2] = QLatin1Char('w');
          if (permissions & QFileDevice::ExeUser)
              result[3] = QLatin1Char('x');
          if (permissions & QFileDevice::ReadGroup)
              result[4] = QLatin1Char('r');
          if (permissions & QFileDevice::WriteGroup)
              result[5] = QLatin1Char('w');
          if (permissions & QFileDevice::ExeGroup)
              result[6] = QLatin1Char('x');
          if (permissions & QFileDevice::ReadOther)
              result[7] = QLatin1Char('r');
          if (permissions & QFileDevice::WriteOther)
              result[8] = QLatin1Char('w');
          if (permissions & QFileDevice::ExeOther)
              result[9] = QLatin1Char('x');
          return result;
      }

      static inline QString sizeString(const QFileInfo &fi)
      {
          if (!fi.isFile())
              return QString();
          const qint64 size = fi.size();
          if (size > 1024 * 1024 * 10)
              return QString::number(size / (1024 * 1024)) + QLatin1Char('M');
          if (size > 1024 * 10)
              return QString::number(size / 1024) + QLatin1Char('K');
          return QString::number(size);
      }

      class DisplayFileSystemModel : public QFileSystemModel {
          Q_OBJECT
      public:
          explicit DisplayFileSystemModel(QObject *parent = nullptr)
              : QFileSystemModel(parent) {}

          enum Roles  {
              SizeRole = Qt::UserRole + 4,
              DisplayableFilePermissionsRole = Qt::UserRole + 5,
              LastModifiedRole = Qt::UserRole + 6,
              UrlStringRole = Qt::UserRole + 7
          };
          Q_ENUM(Roles)

          QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override
          {
              if (index.isValid() && role >= SizeRole) {
                  switch (role) {
                  case SizeRole:
                      return QVariant(sizeString(fileInfo(index)));
                  case DisplayableFilePermissionsRole:
                      return QVariant(permissionString(fileInfo(index)));
                  case LastModifiedRole:
                      return QVariant(fileInfo(index).lastModified().toString(Qt::SystemLocaleShortDate));
                  case UrlStringRole:
                      return QVariant(QUrl::fromLocalFile(filePath(index)).toString());
                  default:
                      break;
                  }
              }
              return QFileSystemModel::data(index, role);
          }

          QHash<int,QByteArray> roleNames() const override
          {
               QHash<int, QByteArray> result = QFileSystemModel::roleNames();
               result.insert(SizeRole, QByteArrayLiteral("size"));
               result.insert(DisplayableFilePermissionsRole, QByteArrayLiteral("displayableFilePermissions"));
               result.insert(LastModifiedRole, QByteArrayLiteral("lastModified"));
               return result;
          }
      };

      int main(int argc, char *argv[])
      {
          QApplication app(argc, argv);

          QQmlApplicationEngine engine;
          qmlRegisterUncreatableType<DisplayFileSystemModel>("io.qt.examples.quick.controls.filesystembrowser", 1, 0,
                                                             "FileSystemModel", "Cannot create a FileSystemModel instance.");
          QFileSystemModel *fsm = new DisplayFileSystemModel(&engine);
          fsm->setRootPath(QDir::homePath());
          fsm->setResolveSymlinks(true);
          engine.rootContext()->setContextProperty("fileSystemModel", fsm);
          engine.rootContext()->setContextProperty("rootPathIndex", fsm->index(fsm->rootPath()));
          engine.load(QUrl(QStringLiteral("qrc:///main.qml")));
          if (engine.rootObjects().isEmpty())
              return -1;

          return app.exec();
      }

      #include "main.moc"