Using Google Drive Api on android studio? - api

Question

i am working on app that integrates google drive api to upload/download files from the user's Google Drive account. i am using
this documentation google drive api v3, but it dont work,
i got this error ->
'java.net.MalformedURLException: Attempt to invoke virtual method 'int java.lang.String.length()' on a null object reference', i can login into google account and log out, but cant uplodad files
public Task<String> newFile(String filepath) {
return Tasks.call(executor, () -> {
File fmdt = new File();
fmdt.setName("contents.json");
java.io.File fp = new java.io.File(filepath);
FileContent mediaContent = new FileContent("application/json",fp);
File mf = null;
try {
mf = driveService.files().create(fmdt, mediaContent).setFields("id").execute();
} catch (Exception e) {
e.printStackTrace();
Log.d("usr","drive-> "+e.getMessage() );
}
if (mf == null) {
throw new IOException("null result");
}
return mf.getId();
});
}

Answer 1

this is how i solve, i guest you re actualli singin on goggle
//the class that handle upload request
public class GoogleDriveHelper {
private final Executor executor = Executors.newSingleThreadExecutor();
private final Drive driveService;
public GoogleDriveHelper(Drive mDriveService) {
this.driveService = mDriveService;
}
public Task<String> newFile(String fileName, String path, String parentId, File file) {
return Tasks.call(executor, () -> {
//use parent to save in especific folder
File fmdt = new File()
.setParents(Collections.singletonList(parentId))
.setMimeType("application/octet-stream")
.setName(nfileName);
File mf = null;
FileContent mediaContent = new FileContent("application/octet-stream", file);
try {
mf = driveService.files().create(fmdt, mediaContent).setFields("id").execute();
} catch (Exception e) {
e.printStackTrace();
}
if (mf == null) {
throw new IOException("null result");
}
return mf.getId();
});
}}
//inicialize google drive service
val credential =
GoogleAccountCredential.usingOAuth2(
ctx,
Collections.singleton(DriveScopes.DRIVE_FILE)
)
credential.selectedAccount = account!!.account
gService = Drive.Builder(
AndroidHttp.newCompatibleTransport(),
GsonFactory(),
credential
).
setApplicationName(APPLICATION_NAME).build();
gDrivehelper = GoogleDriveHelper(gService)