I followed all the steps mentioned in google drive sdk. I created a sample application on my device(android, running jelly bean) and am able to upload a file on to drive. Wh
I have answered this question, and all related Drive on Android questions, over here:
Android Open and Save files to/from Google Drive SDK
In that answer, I posted code for a method that I used to download files from Google Drive (if the following code by itself isn't clear, have a look at the complete answer that I linked to.)
private java.io.File downloadGFileToJFolder(Drive drive, String token, File gFile, java.io.File jFolder) throws IOException {
if (gFile.getDownloadUrl() != null && gFile.getDownloadUrl().length() > 0 ) {
if (jFolder == null) {
jFolder = Environment.getExternalStorageDirectory();
jFolder.mkdirs();
}
try {
HttpClient client = new DefaultHttpClient();
HttpGet get = new HttpGet(gFile.getDownloadUrl());
get.setHeader("Authorization", "Bearer " + token);
HttpResponse response = client.execute(get);
InputStream inputStream = response.getEntity().getContent();
jFolder.mkdirs();
java.io.File jFile = new java.io.File(jFolder.getAbsolutePath() + "/" + getGFileName(gFile)); // getGFileName() is my own method... it just grabs originalFilename if it exists or title if it doesn't.
FileOutputStream fileStream = new FileOutputStream(jFile);
byte buffer[] = new byte[1024];
int length;
while ((length=inputStream.read(buffer))>0) {
fileStream.write(buffer, 0, length);
}
fileStream.close();
inputStream.close();
return jFile;
} catch (IOException e) {
// Handle IOExceptions here...
return null;
}
} else {
// Handle the case where the file on Google Drive has no length here.
return null;
}
}