In the previous blog, I have learned, File uploading to the server from an activity. Now In this article, I’m going to explain how to upload file to the server using Android Service.

In earlier, Normally We use IntentService to perform background task, it is an advanced form of background service in android. That creates a separate thread to perform background operation. But Android Oreo imposed some limitation of background execution. I have written a separate article on it you can read here. So IntentService does not work in Oreo devices and onward while app is in background . In Oreo Android introduced JobIntentService for performing background. It is the modern way of using the background service to perform background task(that run in both cases while app is foreground or background). I have written also a separate article on Working with JobIntentService also. Now we will use JobIntentService for file uploading.

Step for implementation

Create a new class and extends JobIntentService. Now override the onHandleWork() methods. Setup Retrofit instance and Expose API file upload API Place file upload logic in onHandleWork() Create a local BroadCastReceiver() that update the result of service in activity Now expose enqueueWork() to start this service Open MainActivity and starts the JobIntentService We have to pass file path with Intent so write a below code for getting file from camera and intent. Open AndroidManifest and add followings code

Upload Files to Server using Service (Demo App)

Let’s implements above one by one.

1. Create a new class and extends JobIntentService

Create a new project with Basic Template. open app/build .gradle add the dependency

implementation 'com.squareup.retrofit2:retrofit:2.4.0' implementation 'com.squareup.retrofit2:converter-gson:2.4.0' // reactive implementation 'io.reactivex.rxjava2:rxjava:2.1.10' implementation 'io.reactivex.rxjava2:rxandroid:2.0.2' implementation 'com.squareup.retrofit2:adapter-rxjava2:2.4.0' /** * dependency to request the runtime permissions. */ implementation 'com.karumi:dexter:5.0.0' implementation 'com.github.bumptech.glide:glide:4.8.0' annotationProcessor 'com.github.bumptech.glide:compiler:4.8.0'

After that create a new class in named is FileUploadService and extends JobIntentService. Then override the onHandleWork() methods.

package com.wave.fileuploadservice; import android.content.Intent; import android.support.annotation.NonNull; import android.support.v4.app.JobIntentService; /** * Created on : Mar 13, 2019 * Author : AndroidWave */ public class FileUploadService extends JobIntentService { @Override protected void onHandleWork(@NonNull Intent intent) { } }

2. Setup Retrofit instance and Expose API file upload API

Create a interface named RestApiService and expose file upload API

package com.wave.fileuploadservice.service; import io.reactivex.Single; import okhttp3.MultipartBody; import okhttp3.RequestBody; import okhttp3.ResponseBody; import retrofit2.http.Multipart; import retrofit2.http.POST; import retrofit2.http.Part; /** * Created on : Feb 25, 2019 */ public interface RestApiService { @Multipart @POST("fileUpload.php") Single<ResponseBody> onFileUpload(@Part("email") RequestBody mEmail, @Part MultipartBody.Part file); }

Now create instances of Retrofit like this

package com.wave.fileuploadservice.service; import java.util.concurrent.TimeUnit; import okhttp3.OkHttpClient; import okhttp3.Request; import retrofit2.Retrofit; import retrofit2.adapter.rxjava2.RxJava2CallAdapterFactory; import retrofit2.converter.gson.GsonConverterFactory; import static com.wave.fileuploadservice.BuildConfig.BASE_URL; /** * Created on : Feb 25, 2019 * Author : AndroidWave */ public class RetrofitInstance { private static Retrofit retrofit = null; public static RestApiService getApiService() { OkHttpClient client = new OkHttpClient.Builder() .readTimeout(2, TimeUnit.MINUTES) .writeTimeout(2, TimeUnit.MINUTES).addInterceptor(chain -> { Request original = chain.request(); Request.Builder requestBuilder = requestBuilder = original.newBuilder() .method(original.method(), original.body()); Request request = requestBuilder.build(); return chain.proceed(request); }).build(); if (retrofit == null) { retrofit = new Retrofit .Builder() .baseUrl(BASE_URL) .client(client) .addConverterFactory(GsonConverterFactory.create()) .addCallAdapterFactory(RxJava2CallAdapterFactory.create()) .build(); } return retrofit.create(RestApiService.class); } }

3. Create a utility class named is CountingRequestBody

package com.wave.fileuploadservice.service; import android.support.annotation.NonNull; import java.io.IOException; import okhttp3.MediaType; import okhttp3.RequestBody; import okio.Buffer; import okio.BufferedSink; import okio.ForwardingSink; import okio.Okio; import okio.Sink; /** * Created on : Dec 30, 2018 */ public class CountingRequestBody extends RequestBody { private final RequestBody delegate; private final Listener listener; public CountingRequestBody(RequestBody delegate, Listener listener) { this.delegate = delegate; this.listener = listener; } @Override public MediaType contentType() { return delegate.contentType(); } @Override public long contentLength() { try { return delegate.contentLength(); } catch (IOException e) { e.printStackTrace(); } return -1; } @Override public void writeTo(@NonNull BufferedSink sink) throws IOException { CountingSink countingSink = new CountingSink(sink); BufferedSink bufferedSink = Okio.buffer(countingSink); delegate.writeTo(bufferedSink); bufferedSink.flush(); } final class CountingSink extends ForwardingSink { private long bytesWritten = 0; CountingSink(Sink delegate) { super(delegate); } @Override public void write(@NonNull Buffer source, long byteCount) throws IOException { super.write(source, byteCount); bytesWritten += byteCount; listener.onRequestProgress(bytesWritten, contentLength()); } } public interface Listener { void onRequestProgress(long bytesWritten, long contentLength); } }

4.. Open the FileUploadService and do following operation

Furthermore, open the FileUploadService again and call the API likes below

Place file upload logic in onHandleWork()

Create a local BroadCastReceiver() that updates the result in activity

Now expose enqueueWork() to start this service

The complete FileUploadService is looks like this

package com.wave.fileuploadservice; import android.content.Context; import android.content.Intent; import android.support.annotation.NonNull; import android.support.v4.app.JobIntentService; import android.support.v4.content.LocalBroadcastManager; import android.util.Log; import com.wave.fileuploadservice.service.CountingRequestBody; import com.wave.fileuploadservice.service.RestApiService; import com.wave.fileuploadservice.service.RetrofitInstance; import com.wave.fileuploadservice.utils.MIMEType; import io.reactivex.BackpressureStrategy; import io.reactivex.Flowable; import io.reactivex.FlowableEmitter; import io.reactivex.android.schedulers.AndroidSchedulers; import io.reactivex.disposables.Disposable; import io.reactivex.schedulers.Schedulers; import java.io.File; import okhttp3.MediaType; import okhttp3.MultipartBody; import okhttp3.RequestBody; public class FileUploadService extends JobIntentService { private static final String TAG = "FileUploadService"; Disposable mDisposable; /** * Unique job ID for this service. */ private static final int JOB_ID = 102; public static void enqueueWork(Context context, Intent intent) { enqueueWork(context, FileUploadService.class, JOB_ID, intent); } @Override public void onCreate() { super.onCreate(); } @Override protected void onHandleWork(@NonNull Intent intent) { /** * Download/Upload of file * The system or framework is already holding a wake lock for us at this point */ // get file file here String mFilePath = intent.getStringExtra("mFilePath"); if (mFilePath == null) { Log.e(TAG, "onHandleWork: Invalid file URI"); return; } RestApiService apiService = RetrofitInstance.getApiService(); Flowable<Double> fileObservable = Flowable.create(emitter -> { apiService.onFileUpload(createRequestBodyFromText("info@androidwave.com"), createMultipartBody(mFilePath, emitter)).blockingGet(); emitter.onComplete(); }, BackpressureStrategy.LATEST); mDisposable = fileObservable.subscribeOn(Schedulers.computation()) .observeOn(AndroidSchedulers.mainThread()) .subscribe(progress -> onProgress(progress), throwable -> onErrors(throwable), () -> onSuccess()); } private void onErrors(Throwable throwable) { sendBroadcastMeaasge("Error in file upload " + throwable.getMessage()); Log.e(TAG, "onErrors: ", throwable); } private void onProgress(Double progress) { sendBroadcastMeaasge("Uploading in progress... " + (int) (100 * progress)); Log.i(TAG, "onProgress: " + progress); } private void onSuccess() { sendBroadcastMeaasge("File uploading successful "); Log.i(TAG, "onSuccess: File Uploaded"); } public void sendBroadcastMeaasge(String message) { Intent localIntent = new Intent("my.own.broadcast"); localIntent.putExtra("result", message); LocalBroadcastManager.getInstance(this).sendBroadcast(localIntent); } private RequestBody createRequestBodyFromFile(File file, String mimeType) { return RequestBody.create(MediaType.parse(mimeType), file); } private RequestBody createRequestBodyFromText(String mText) { return RequestBody.create(MediaType.parse("text/plain"), mText); } /** * return multi part body in format of FlowableEmitter */ private MultipartBody.Part createMultipartBody(String filePath, FlowableEmitter<Double> emitter) { File file = new File(filePath); return MultipartBody.Part.createFormData("myFile", file.getName(), createCountingRequestBody(file, MIMEType.IMAGE.value, emitter)); } private RequestBody createCountingRequestBody(File file, String mimeType, FlowableEmitter<Double> emitter) { RequestBody requestBody = createRequestBodyFromFile(file, mimeType); return new CountingRequestBody(requestBody, (bytesWritten, contentLength) -> { double progress = (1.0 * bytesWritten) / contentLength; emitter.onNext(progress); }); } }

4.1 Declare service inside the Manifest

For Pre-Oreo devices => We have to set uses permission – WAKE_LOCK permission

For Oreo device => you have to declare android.permission.BIND_JOB_SERVICE

<!--for JobIntentService--> <uses-permission android:name="android.permission.WAKE_LOCK" /> <service android:name=".FileUploadService" android:permission="android.permission.BIND_JOB_SERVICE" />

5. Open activity_main.xml and add below code

<?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".MainActivity"> <ImageView android:id="@+id/ivDisplayImage" android:layout_width="wrap_content" android:layout_height="200dp" android:layout_marginStart="8dp" android:layout_marginTop="56dp" android:layout_marginEnd="8dp" android:layout_marginBottom="16dp" app:layout_constraintBottom_toTopOf="@+id/tvSelectedFilePath" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintHorizontal_bias="0.5" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toTopOf="parent" app:layout_constraintVertical_chainStyle="packed" app:srcCompat="@drawable/photo" /> <Button android:id="@+id/buttonUpload" android:layout_width="200dp" android:layout_height="wrap_content" android:layout_marginStart="8dp" android:layout_marginTop="8dp" android:layout_marginEnd="8dp" android:background="@color/colorAccent" android:text="UPLOAD" android:textColor="#fff" android:textSize="18sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintHorizontal_bias="0.5" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@+id/tvSelectedFilePath" /> <TextView android:id="@+id/tvSelectedFilePath" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginStart="8dp" android:layout_marginTop="32dp" android:layout_marginEnd="8dp" android:layout_marginBottom="16dp" android:gravity="center" android:hint="Selected file" android:textSize="18sp" android:textColor="#161616" app:layout_constraintBottom_toTopOf="@+id/buttonUpload" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintHorizontal_bias="0.5" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@+id/ivDisplayImage" /> <ImageView android:id="@+id/imageView2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginStart="8dp" android:layout_marginEnd="8dp" android:layout_marginBottom="16dp" app:layout_constraintBottom_toTopOf="@+id/tvSelectedFilePath" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintStart_toStartOf="parent" app:srcCompat="@drawable/pencil" /> <TextView android:id="@+id/textView2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginStart="8dp" android:layout_marginTop="32dp" android:layout_marginEnd="8dp" android:text="File Uploading using Service Demo App" android:textColor="@color/colorPrimary" android:textSize="18sp" android:textStyle="bold" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/txvResult" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginStart="8dp" android:layout_marginTop="8dp" android:layout_marginEnd="8dp" android:layout_marginBottom="8dp" android:text="Result" android:textSize="17sp" android:textStyle="bold" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@+id/buttonUpload" /> </android.support.constraint.ConstraintLayout>

6. Write a File Provider

In this demo, we will capture image from camera and gallery with the help of FileProvider. I have written a separate article on capturing image from camera/gallery using FileProvider. I would like to suggest Read this article more clarity.

6.1 Go to res => xml => create a new xml file named is file_provider_path.xml and paste that code

<?xml version="1.0" encoding="utf-8"?> <paths> <external-path name="my_images" path="Android/data/com.wave.fileuploadservice/files/Pictures" /> <!-- replace com.wave.fileuploadservice with your package name --> </paths>

6.2 Now open the AndroidManifest.xml and declare file provider inside the application tag

<provider android:name="android.support.v4.content.FileProvider" android:authorities="${applicationId}.provider" android:exported="false" android:grantUriPermissions="true"> <meta-data android:name="android.support.FILE_PROVIDER_PATHS" android:resource="@xml/file_provider_paths" /> </provider>

6.3 Declare storage and camera permission in manifest

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" /> <uses-permission android:name="android.permission.CAMERA" /> <uses-permission android:name="android.permission.INTERNET" /> <uses-feature android:name="android.hardware.camera" /> <uses-feature android:name="android.hardware.camera.autofocus" /> <uses-feature android:name="android.hardware.camera.flash" />

7. Finally, Open the Activity (MainActivity) add do below operation

We are using Dexter for using permission on run time. So Expose requestStoragePermission() for requesting permission

Create methods for preparing intent for camera and gallery names is startCamera() and chooseGallery ()

() Handle callback result in onActivityResult()

Register and UnRegister local BroadcastReceiver

Final code of Activity looks like below

package com.wave.fileuploadservice; import android.Manifest; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.database.Cursor; import android.net.Uri; import android.os.Bundle; import android.os.Environment; import android.provider.MediaStore; import android.support.v4.content.FileProvider; import android.support.v4.content.LocalBroadcastManager; import android.support.v7.app.AlertDialog; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.Button; import android.widget.ImageView; import android.widget.TextView; import android.widget.Toast; import com.bumptech.glide.Glide; import com.bumptech.glide.request.RequestOptions; import com.karumi.dexter.Dexter; import com.karumi.dexter.MultiplePermissionsReport; import com.karumi.dexter.PermissionToken; import com.karumi.dexter.listener.PermissionRequest; import com.karumi.dexter.listener.multi.MultiplePermissionsListener; import java.io.File; import java.io.IOException; import java.util.Calendar; import java.util.List; public class MainActivity extends AppCompatActivity implements View.OnClickListener { static final int REQUEST_TAKE_PHOTO = 101; static final int REQUEST_GALLERY_PHOTO = 102; File mPhotoFile; ImageView ivDisplayImage; Button buttonUpload; TextView tvSelectedFilePath; ImageView ivSelectImage; TextView txvResult; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); ivDisplayImage = findViewById(R.id.ivDisplayImage); buttonUpload = findViewById(R.id.buttonUpload); tvSelectedFilePath = findViewById(R.id.tvSelectedFilePath); ivSelectImage = findViewById(R.id.imageView2); txvResult = findViewById(R.id.txvResult); buttonUpload.setOnClickListener(this); ivSelectImage.setOnClickListener(this); } @Override public void onClick(View v) { switch (v.getId()) { case R.id.buttonUpload: if (tvSelectedFilePath.getText().toString().isEmpty()) { Toast.makeText(this, "Select file first", Toast.LENGTH_LONG).show(); return; } Intent mIntent = new Intent(this, FileUploadService.class); mIntent.putExtra("mFilePath", tvSelectedFilePath.getText().toString()); FileUploadService.enqueueWork(this, mIntent); break; case R.id.imageView2: selectImage(); break; } } /** * Alert dialog for capture or select from galley */ private void selectImage() { final CharSequence[] items = { "Take Photo", "Choose from Library", "Cancel" }; AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this); builder.setItems(items, (dialog, item) -> { if (items[item].equals("Take Photo")) { requestStoragePermission(true); } else if (items[item].equals("Choose from Library")) { requestStoragePermission(false); } else if (items[item].equals("Cancel")) { dialog.dismiss(); } }); builder.show(); } /** * Requesting multiple permissions (storage and camera) at once * This uses multiple permission model from dexter * On permanent denial opens settings dialog */ private void requestStoragePermission(boolean isCamera) { Dexter.withActivity(this) .withPermissions(Manifest.permission.WRITE_EXTERNAL_STORAGE, Manifest.permission.CAMERA) .withListener(new MultiplePermissionsListener() { @Override public void onPermissionsChecked(MultiplePermissionsReport report) { // check if all permissions are granted if (report.areAllPermissionsGranted()) { if (isCamera) { startCamera(); } else { chooseGallery(); } } // check for permanent denial of any permission if (report.isAnyPermissionPermanentlyDenied()) { // show alert dialog navigating to Settings chooseGallery(); } } @Override public void onPermissionRationaleShouldBeShown(List<PermissionRequest> permissions, PermissionToken token) { token.continuePermissionRequest(); } }) .withErrorListener( error -> Toast.makeText(getApplicationContext(), "Error occurred! ", Toast.LENGTH_SHORT) .show()) .onSameThread() .check(); } public void startCamera() { mPhotoFile = newFile(); Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE); if (takePictureIntent.resolveActivity(getPackageManager()) != null) { if (mPhotoFile != null) { Uri photoURI = FileProvider.getUriForFile(this, BuildConfig.APPLICATION_ID + ".provider", mPhotoFile); takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI); startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO); } } } public void chooseGallery() { Intent pickPhoto = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI); pickPhoto.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION); startActivityForResult(pickPhoto, REQUEST_GALLERY_PHOTO); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { if (resultCode == RESULT_OK) { if (requestCode == REQUEST_TAKE_PHOTO) { tvSelectedFilePath.setText(mPhotoFile.getAbsolutePath()); Glide.with(MainActivity.this) .load(mPhotoFile) .apply(new RequestOptions().centerCrop().circleCrop()) .into(ivDisplayImage); } else if (requestCode == REQUEST_GALLERY_PHOTO) { Uri selectedImage = data.getData(); tvSelectedFilePath.setText(getRealPathFromUri(selectedImage)); Glide.with(MainActivity.this) .load(getRealPathFromUri(selectedImage)) .apply(new RequestOptions().centerCrop().circleCrop()) .into(ivDisplayImage); } } } public File newFile() { Calendar cal = Calendar.getInstance(); long timeInMillis = cal.getTimeInMillis(); String mFileName = String.valueOf(timeInMillis) + ".jpeg"; File mFilePath = getFilePath(); try { File newFile = new File(mFilePath.getAbsolutePath(), mFileName); newFile.createNewFile(); return newFile; } catch (IOException e) { e.printStackTrace(); } return null; } public File getFilePath() { return getExternalFilesDir(Environment.DIRECTORY_PICTURES); } public String getRealPathFromUri(Uri contentUri) { Cursor cursor = null; try { String[] proj = { MediaStore.Images.Media.DATA }; cursor = getContentResolver().query(contentUri, proj, null, null, null); assert cursor != null; int columnIndex = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA); cursor.moveToFirst(); return cursor.getString(columnIndex); } finally { if (cursor != null) { cursor.close(); } } } @Override protected void onResume() { super.onResume(); IntentFilter intentFilter = new IntentFilter("my.own.broadcast"); LocalBroadcastManager.getInstance(this) .registerReceiver(myLocalBroadcastReceiver, intentFilter); } private BroadcastReceiver myLocalBroadcastReceiver = new BroadcastReceiver() { @Override public void onReceive(Context context, Intent intent) { String result = intent.getStringExtra("result"); txvResult.setText(result); } }; @Override protected void onPause() { super.onPause(); LocalBroadcastManager.getInstance(this).unregisterReceiver(myLocalBroadcastReceiver); } }

I’m new in Android so If you have any queries or suggestions, feel free to ask them in the comment section below. Happy Coding 🙂

Download Sample Project- Upload Files to Server using Service