Dropbox Sync API Android - Updating Cached Files

Question

I am facing trouble in updating the existing cached file within my Android Application.

for(DbxFileInfo fInfo : fileList)
{
    Log.d(TAG, "File Path = "+fInfo.path.toString());
    String fileName = fInfo.path.getName().trim();

    try
    {
        DbxPath tempFilePath    = new DbxPath(fInfo.path.toString());
        DbxFile tempFile        = mDbFileSystem.open(tempFilePath);

        if(tempFile.getSyncStatus().isCached)
        {
            Log.v(TAG, "File is already cached !");

            if(tempFile.getSyncStatus().isLatest)
            {
                Log.v(TAG, "File's Latest Version is Cached !");
            }
            else
            {
                Log.v(TAG, "File's Latest Version is not Cached !");
            }
        }

        try
        {
            tempFile.getNewerStatus();
        }
        catch(Exception dBException)
        {
            Log.e(TAG, "Error while getting newer Status !");
        }

        InputStream input       = new BufferedInputStream(tempFile.getReadStream());
        OutputStream output     = new FileOutputStream(cntx.getFilesDir() + "/SyncedData/" + fileName);

        byte data[] = new byte[1024];
        int count;

        //total size is in Bytes
        while ((count = input.read(data)) != -1)
        {
            totalBytesDownloaded += count;
            publishProgress((int) (totalBytesDownloaded * 100/totalFileSize));
            output.write(data, 0, count);
        }

        output.flush();
        output.close();
        input.close();
        tempFile.close();
        mDbFileSystem.delete(tempFile.getPath());

        result = true;
    }
    catch(Exception e)
    {
        Log.e(TAG, "Error occured while downloading files !, Error = "+e.toString());
        result = false;
    }
}

I am putting different files with same names on my Synced Dropbox folder and after Downloading them i am getting the older version of files.
Is there any way i can update my existing cached files or Clear the Dropbox Cache (that is within my App) Any help is highly appreciated, thanks.

I have faced the same problem and for the time being accepted that it often takes two syncs in my app to update the overwritten files. Does your implementation fetch the updates on the second request? — cYrixmorten
Oh, the updates fetched by my App are very uncertain :( Sometimes a single new files arrive and the rest are previous versions. Some times i receive all the previous versions. — Salman Khakwani

user94559 user94559 · Accepted Answer · 2014-01-06T19:57:35

Here's how the Sync API works:

It constantly syncs metadata (what files exist and their revisions) and notifies you via listeners you set up on the file system.
For open files, it downloads any newer version of the file available and notifies you via the listener you set up on the file itself.

So if you want to get the latest version of a file, you need to open the file and hold it open while waiting for the listener to notify you that the newer version of the file is cached. Then you can call update to get access to that new data.

EDIT: Pasting code from https://www.dropbox.com/developers/sync/start/android#listeners:

DbxFileStatus status = testFile.getSyncStatus();
if (!status.isCached) {
    testFile.addListener(new DbxFile.Listener() {
        @Override
        public void onFileChange(DbxFile file) {
            // Check testFile.getSyncStatus() and read if it's ready
        }
    });
    // Check if testFile.getSyncStatus() is ready already to ensure nothing
    // was missed while adding the listener
}

Dropbox Sync API Android - Updating Cached Files

3 Answers