+ * This happens when a download or upload is started or ended for a file.
+ *
+ * This method is necessary by now to update the user interface of the double-pane layout in tablets
+ * because methods {@link FileDownloaderBinder#isDownloading(Account, OCFile)} and {@link FileUploaderBinder#isUploading(Account, OCFile)}
+ * won't provide the needed response before the method where this is called finishes.
+ *
+ * TODO Remove this when the transfer state of a file is kept in the database (other thing TODO)
+ *
+ * @param file OCFile which state changed.
+ * @param downloading Flag signaling if the file is now downloading.
+ * @param uploading Flag signaling if the file is now uploading.