Android - Google Drive SDK - 打开文件

Question

I am used to opening my files in my apps using the next code:

public void openFile(@NonNull String uri) {
        checkNotNull(uri);
        File file = new File(uri);

        String dataType = null;
        if (ContentTypeUtils.isPdf(uri)) dataType = "application/pdf";
        else if (ContentTypeUtils.isImage(uri)) dataType = "image/*";

        if (file.exists() && dataType != null) {
            Intent target = new Intent(Intent.ACTION_VIEW);

            target.setDataAndType(Uri.fromFile(file), dataType);
            target.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);

            Intent intent = Intent.createChooser(target, "Open file");
            try {
                startActivity(intent);
            } catch (ActivityNotFoundException e) {
                e.printStackTrace();
                Log.e(TAG, "There is a problem when opening the file :(");
            }
        } else {
            Toast.makeText(getContext(), "Invalido", Toast.LENGTH_LONG).show();
        }
    }

I had always used static files so this was enough, but now I am using the Google Drive SDK for Android. I possess the driveId of the file I want to open but the problem is I cannot find a clean way to open the file contents I obtain by doing this:

Drive.DriveApi.fetchDriveId(mGoogleApiClient, documentFile.getDriveId())
            .setResultCallback(driveIdResult -> {
                PendingResult<DriveApi.DriveContentsResult> open =
                        driveIdResult.getDriveId().asDriveFile().open(
                        mGoogleApiClient,
                        DriveFile.MODE_READ_ONLY,
                        null);

                open.setResultCallback(result -> {
                    DriveContents contents = result.getDriveContents();
                    InputStream inputStream = contents.getInputStream();
                    // I know I can get the input stream, and use it to write a new file.

                });
            });

So the only thing that comes to my mind is creating a static route to create a file every time I have to open it, and erasing it every time I have to open a new file.

What I have understood up until now is that the Google Drive API for Android already saves an instance of the file so what I have in mind sounds unnecessary, I would like to know if there is a better way to achieve this. Is there a way I can open the file and do something similar to what I do with the Intent.ACTION_VIEW in a cleaner way?

Thanks in advance.

Answer 1

Well since it seems this will not be answered I will post what I did. All I did was create a temp file where I put my contents to be read. I still don't know if it was the best choice so this question will still be opened for a better answer.

open.setResultCallback(result -> {
                    DriveContents contents = result.getDriveContents();
                    InputStream inputStream = contents.getInputStream();
                    writeTempFile(inputStream);
                });

And here the implementation of the `writeTempFile`:

    private synchronized File writeTempFile(@NonNull InputStream inputStream) {
        checkNotNull(inputStream);
        File filePath = new File(mActivity.getFilesDir(), "TempFiles");
        if (!filePath.exists()) filePath.mkdirs();
        File file = new File(filePath, TEMP_FILE);
        try {
            OutputStream outputStream = new FileOutputStream(file);
            IOUtils.copyLarge(inputStream, outputStream);
            IOUtils.closeQuietly(inputStream);
            IOUtils.closeQuietly(outputStream);
        } catch (IOException e) {
            e.printStackTrace();
        }

        return file;
    }