C++ G_DRIVE_GET_IFACE函数代码示例

/**
 * g_drive_stop:
 * @drive: a #GDrive.
 * @flags: flags affecting the unmount if required for stopping.
 * @mount_operation: (allow-none): a #GMountOperation or %NULL to avoid
 *     user interaction.
 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 * @callback: (allow-none): a #GAsyncReadyCallback, or %NULL.
 * @user_data: user data to pass to @callback
 *
 * Asynchronously stops a drive.
 *
 * When the operation is finished, @callback will be called.
 * You can then call g_drive_stop_finish() to obtain the
 * result of the operation.
 *
 * Since: 2.22
 */
void
g_drive_stop (GDrive               *drive,
              GMountUnmountFlags    flags,
              GMountOperation      *mount_operation,
              GCancellable         *cancellable,
              GAsyncReadyCallback   callback,
              gpointer              user_data)
{
  GDriveIface *iface;

  g_return_if_fail (G_IS_DRIVE (drive));

  iface = G_DRIVE_GET_IFACE (drive);

  if (iface->stop == NULL)
    {
      g_task_report_new_error (drive, callback, user_data,
                               g_drive_start,
                               G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
                               _("drive doesn't implement stop"));
      return;
    }

  (* iface->stop) (drive, flags, mount_operation, cancellable, callback, user_data);
}

/**
 * g_drive_eject_with_operation:
 * @drive: a #GDrive.
 * @flags: flags affecting the unmount if required for eject
 * @mount_operation: (allow-none): a #GMountOperation or %NULL to avoid
 *     user interaction.
 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 * @callback: (allow-none): a #GAsyncReadyCallback, or %NULL.
 * @user_data: user data passed to @callback.
 *
 * Ejects a drive. This is an asynchronous operation, and is
 * finished by calling g_drive_eject_with_operation_finish() with the @drive
 * and #GAsyncResult data returned in the @callback.
 *
 * Since: 2.22
 **/
void
g_drive_eject_with_operation (GDrive              *drive,
                              GMountUnmountFlags   flags,
                              GMountOperation     *mount_operation,
                              GCancellable        *cancellable,
                              GAsyncReadyCallback  callback,
                              gpointer             user_data)
{
  GDriveIface *iface;

  g_return_if_fail (G_IS_DRIVE (drive));

  iface = G_DRIVE_GET_IFACE (drive);

  if (iface->eject == NULL && iface->eject_with_operation == NULL)
    {
      g_task_report_new_error (drive, callback, user_data,
                               g_drive_eject_with_operation,
                               G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
                               /* Translators: This is an error
                                * message for drive objects that
                                * don't implement any of eject or eject_with_operation. */
                               _("drive doesn't implement eject or eject_with_operation"));
      return;
    }

  if (iface->eject_with_operation != NULL)
    (* iface->eject_with_operation) (drive, flags, mount_operation, cancellable, callback, user_data);
  else
    (* iface->eject) (drive, flags, cancellable, callback, user_data);
}

/**
 * g_drive_has_media:
 * @drive: a #GDrive.
 * 
 * Checks if the @drive has media. Note that the OS may not be polling
 * the drive for media changes; see g_drive_is_media_check_automatic()
 * for more details.
 * 
 * Returns: %TRUE if @drive has media, %FALSE otherwise.
 **/
gboolean
g_drive_has_media (GDrive *drive)
{
  GDriveIface *iface;

  g_return_val_if_fail (G_IS_DRIVE (drive), FALSE);

  iface = G_DRIVE_GET_IFACE (drive);

  return (* iface->has_media) (drive);
}

/**
 * g_drive_is_media_removable:
 * @drive: a #GDrive.
 * 
 * Checks if the @drive supports removable media.
 * 
 * Returns: %TRUE if @drive supports removable media, %FALSE otherwise.
 **/
gboolean
g_drive_is_media_removable (GDrive *drive)
{
  GDriveIface *iface;

  g_return_val_if_fail (G_IS_DRIVE (drive), FALSE);

  iface = G_DRIVE_GET_IFACE (drive);

  return (* iface->is_media_removable) (drive);
}

/**
 * g_drive_is_media_check_automatic:
 * @drive: a #GDrive.
 * 
 * Checks if @drive is capabable of automatically detecting media changes.
 * 
 * Returns: %TRUE if the @drive is capabable of automatically detecting 
 *     media changes, %FALSE otherwise.
 **/
gboolean
g_drive_is_media_check_automatic (GDrive *drive)
{
  GDriveIface *iface;

  g_return_val_if_fail (G_IS_DRIVE (drive), FALSE);

  iface = G_DRIVE_GET_IFACE (drive);

  return (* iface->is_media_check_automatic) (drive);
}

/**
 * g_drive_get_volumes:
 * @drive: a #GDrive.
 * 
 * Get a list of mountable volumes for @drive.
 *
 * The returned list should be freed with g_list_free(), after
 * its elements have been unreffed with g_object_unref().
 * 
 * Returns: (element-type GVolume) (transfer full): #GList containing any #GVolume objects on the given @drive.
 **/
GList *
g_drive_get_volumes (GDrive *drive)
{
  GDriveIface *iface;

  g_return_val_if_fail (G_IS_DRIVE (drive), NULL);

  iface = G_DRIVE_GET_IFACE (drive);

  return (* iface->get_volumes) (drive);
}

/**
 * g_drive_get_icon:
 * @drive: a #GDrive.
 * 
 * Gets the icon for @drive.
 * 
 * Returns: (transfer full): #GIcon for the @drive.
 *    Free the returned object with g_object_unref().
 **/
GIcon *
g_drive_get_icon (GDrive *drive)
{
  GDriveIface *iface;
  
  g_return_val_if_fail (G_IS_DRIVE (drive), NULL);

  iface = G_DRIVE_GET_IFACE (drive);

  return (* iface->get_icon) (drive);
}

/**
 * g_drive_is_removable:
 * @drive: a #GDrive.
 *
 * Checks if the #GDrive and/or its media is considered removable by the user.
 * See g_drive_is_media_removable().
 *
 * Returns: %TRUE if @drive and/or its media is considered removable, %FALSE otherwise.
 *
 * Since: 2.50
 **/
gboolean
g_drive_is_removable (GDrive *drive)
{
  GDriveIface *iface;

  g_return_val_if_fail (G_IS_DRIVE (drive), FALSE);

  iface = G_DRIVE_GET_IFACE (drive);
  if (iface->is_removable != NULL)
    return iface->is_removable (drive);

  return FALSE;
}

/**
 * g_drive_can_poll_for_media:
 * @drive: a #GDrive.
 * 
 * Checks if a drive can be polled for media changes.
 * 
 * Returns: %TRUE if the @drive can be polled for media changes,
 *     %FALSE otherwise.
 **/
gboolean
g_drive_can_poll_for_media (GDrive *drive)
{
  GDriveIface *iface;

  g_return_val_if_fail (G_IS_DRIVE (drive), FALSE);

  iface = G_DRIVE_GET_IFACE (drive);

  if (iface->poll_for_media == NULL)
    return FALSE;

  return (* iface->can_poll_for_media) (drive);
}

/**
 * g_drive_get_sort_key:
 * @drive: A #GDrive.
 *
 * Gets the sort key for @drive, if any.
 *
 * Returns: Sorting key for @drive or %NULL if no such key is available.
 *
 * Since: 2.32
 */
const gchar *
g_drive_get_sort_key (GDrive  *drive)
{
  const gchar *ret = NULL;
  GDriveIface *iface;

  g_return_val_if_fail (G_IS_DRIVE (drive), NULL);

  iface = G_DRIVE_GET_IFACE (drive);
  if (iface->get_sort_key != NULL)
    ret = iface->get_sort_key (drive);

  return ret;
}

/**
 * g_drive_can_stop:
 * @drive: a #GDrive.
 *
 * Checks if a drive can be stopped.
 *
 * Returns: %TRUE if the @drive can be stopped, %FALSE otherwise.
 *
 * Since: 2.22
 */
gboolean
g_drive_can_stop (GDrive *drive)
{
  GDriveIface *iface;

  g_return_val_if_fail (G_IS_DRIVE (drive), FALSE);

  iface = G_DRIVE_GET_IFACE (drive);

  if (iface->can_stop == NULL)
    return FALSE;

  return (* iface->can_stop) (drive);
}

/**
 * g_drive_get_start_stop_type:
 * @drive: a #GDrive.
 *
 * Gets a hint about how a drive can be started/stopped.
 *
 * Returns: A value from the #GDriveStartStopType enumeration.
 *
 * Since: 2.22
 */
GDriveStartStopType
g_drive_get_start_stop_type (GDrive *drive)
{
  GDriveIface *iface;

  g_return_val_if_fail (G_IS_DRIVE (drive), FALSE);

  iface = G_DRIVE_GET_IFACE (drive);

  if (iface->get_start_stop_type == NULL)
    return G_DRIVE_START_STOP_TYPE_UNKNOWN;

  return (* iface->get_start_stop_type) (drive);
}

/**
 * g_drive_get_identifier:
 * @drive: a #GDrive
 * @kind: the kind of identifier to return
 *
 * Gets the identifier of the given kind for @drive.
 *
 * Returns: a newly allocated string containing the
 *     requested identfier, or %NULL if the #GDrive
 *     doesn't have this kind of identifier.
 */
char *
g_drive_get_identifier (GDrive     *drive,
			const char *kind)
{
  GDriveIface *iface;

  g_return_val_if_fail (G_IS_DRIVE (drive), NULL);
  g_return_val_if_fail (kind != NULL, NULL);

  iface = G_DRIVE_GET_IFACE (drive);

  if (iface->get_identifier == NULL)
    return NULL;
  
  return (* iface->get_identifier) (drive, kind);
}

/**
 * g_drive_get_symbolic_icon:
 * @drive: a #GDrive.
 * 
 * Gets the icon for @drive.
 * 
 * Returns: (transfer full): symbolic #GIcon for the @drive.
 *    Free the returned object with g_object_unref().
 *
 * Since: 2.34
 **/
GIcon *
g_drive_get_symbolic_icon (GDrive *drive)
{
  GDriveIface *iface;
  GIcon *ret;

  g_return_val_if_fail (G_IS_DRIVE (drive), NULL);

  iface = G_DRIVE_GET_IFACE (drive);

  if (iface->get_symbolic_icon != NULL)
    ret = iface->get_symbolic_icon (drive);
  else
    ret = g_themed_icon_new_with_default_fallbacks ("drive-removable-media-symbolic");

  return ret;
}

/**
 * g_drive_stop_finish:
 * @drive: a #GDrive.
 * @result: a #GAsyncResult.
 * @error: a #GError, or %NULL
 *
 * Finishes stopping a drive.
 *
 * Returns: %TRUE if the drive has been stopped successfully,
 *     %FALSE otherwise.
 *
 * Since: 2.22
 */
gboolean
g_drive_stop_finish (GDrive        *drive,
                     GAsyncResult  *result,
                     GError       **error)
{
  GDriveIface *iface;

  g_return_val_if_fail (G_IS_DRIVE (drive), FALSE);
  g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE);

  if (g_async_result_legacy_propagate_error (result, error))
    return FALSE;
  else if (g_async_result_is_tagged (result, g_drive_start))
    return g_task_propagate_boolean (G_TASK (result), error);

  iface = G_DRIVE_GET_IFACE (drive);

  return (* iface->stop_finish) (drive, result, error);
}