I am creating application where there is an option of checkbox allowing user to change wallpaper automatically after 30 seconds. I am using JobScheduler and have passed arraylist of images by serializing them to JsonArray and then to String and passed it using PersistanceBundle:
JsonArray result = (JsonArray) new Gson().toJsonTree(wallpaperModelArrayList,
new TypeToken<List<WallpaperModel>>() {
}.getType());
PersistableBundle persistableBundle=new PersistableBundle();
persistableBundle.putString("wallpaper",result.toString());
mJobScheduler = (JobScheduler)
getSystemService(Context.JOB_SCHEDULER_SERVICE);
JobInfo.Builder builder = new JobInfo.Builder(1,
new ComponentName(getPackageName(),
JobSchedulerService.class.getName()));
builder.setExtras(persistableBundle);
builder.setPeriodic(30000);
And my JobService class:
public class JobSchedulerService extends JobService {
private static final String TAG = "JobSchedulerService";
private String images;
#Override
public boolean onStartJob(JobParameters params) {
Log.i(TAG, "onStartJob:");
images = params.getExtras().getString("wallpaper");
changeWallpaper(params);
return true;
}
#Override
public boolean onStopJob(JobParameters params) {
//Log.i(TAG, "onStopJob:");
return true;
}
private void changeWallpaper(JobParameters params) {
Gson gson = new Gson();
Type listType = new TypeToken<List<WallpaperModel>>(){}.getType();
List<WallpaperModel> list = gson.fromJson(images, listType);
Glide.with(this)
.load(list.get(0).getUrlImage())
.asBitmap()
.into(new SimpleTarget<Bitmap>() {
#Override
public void onResourceReady(Bitmap resource, GlideAnimation<? super
Bitmap> glideAnimation) {
try {
WallpaperManager.getInstance(getApplicationContext()).setBitmap(resource);
} catch (IOException e) {
e.printStackTrace();
}
}
});
jobFinished(params, false);
}
}
I don't know how to set wallpaper(images one by one) after every 30 secs out of the list I have in JobService?Can Anyone tell me how setperiodic function works(what happens after 30secs)? This approach can be wrong. Can anyone guide me on how to do this? Thanks in advance.
Related
I want to WorkManager startWork() to be called every time the user connects to the internet through wifi or 3g/4g/5g.
It calls only one time at the start where I register it.
enqueuing work when a user signs in.
Worker.startWorkManager(SignInActivity.this);
startActivity(new Intent(SignInActivity.this,UsersActivity.class);
it never calls again whenever the user turns Wifi OFF and ON again regardless app is in foreground or background or app is killed through swiped from recent apps.
I want it to be called every time user turned Wifi OFF and ON in every scenario i.e foreground, background, or app is killed.
Worker.class
public class Worker {
public Worker(Context context, WorkerParameters workerParams) {
}
public static void startWorkManager(Context context) {
Constraints constraints = new Constraints.Builder()
.setRequiredNetworkType(NetworkType.CONNECTED)
.build();
WorkManager.getInstance(context).enqueueUniqueWork(Constants.TAG_SYNC_DATA, ExistingWorkPolicy.KEEP, new OneTimeWorkRequest.Builder(SyncDataWorker.class)
.addTag(Constants.TAG_SYNC_DATA)
.setConstraints(constraints)
.build());
}
}
SyncDataWorker.class
public class SyncDataWorker extends ListenableWorker {
public SyncDataWorker(
#NonNull Context context,
#NonNull WorkerParameters params) {
super(context, params);
}
#NonNull
#Override
public ListenableFuture<Result> startWork() {
return CallbackToFutureAdapter.getFuture(completer -> {
AsyncCallback callback = new AsyncCallback() {
#Override
public void onFailure(Exception e) {
completer.setException(e);
}
#Override
public void onSuccess() {
completer.set(Result.success());
}
#Override
public void onRetry() {
completer.set(Result.retry());
}
};
new AsyncSyncData(getApplicationContext(), callback).execute();
return callback;
});
}
}
AsyncSynData.class
public class AsyncSyncData extends AsyncTask<Void, Void, Void> {
private final Context context;
ArrayList<message> messageArrayListNotSync;
ArrayList<unread_messages> unreadMessagesArrayList;
String user_id = "";
private AsyncCallback callback = null;
public AsyncSyncData(Context context, AsyncCallback callback) {
this.context = context;
messageArrayListNotSync = new ArrayList<>();
unreadMessagesArrayList = new ArrayList<>();
this.callback = callback;
}
#Override
protected Void doInBackground(Void... voids) {
AppDatabase db = AppDatabase.getAppDatabase(context);
user user = null;
ArrayList<user> userArrayList = new ArrayList<>(db.applicationDao().getAllUsers());
if (userArrayList.size() > 0) {
user = userArrayList.get(0);
}
messageArrayListNotSync = new ArrayList<>(db.applicationDao().getAllMessagesNotSync(!user_id.isEmpty() ? user_id : user.threadId));
unreadMessagesArrayList = new ArrayList<>(db.applicationDao().getUnreadMessageStatus());
System.out.println("messageArrayListNotSync: " + messageArrayListNotSync);
System.out.println("unreadMessagesArrayList: " + unreadMessagesArrayList);
try {
JSONObject jsonObject = new JSONObject();
jsonObject.put("user_id", !user_id.isEmpty() ? user_id : user.threadId);
Gson gson = new GsonBuilder().create();
JsonArray json_messages = gson.toJsonTree(messageArrayListNotSync).getAsJsonArray();
JsonArray json_unread_messages = gson.toJsonTree(unreadMessagesArrayList).getAsJsonArray();
jsonObject.put("messages", json_messages);
jsonObject.put("unread_messages", json_unread_messages);
RequestHandler.postRequest("/messages", jsonObject, context, new VolleyCallback() {
#Override
public void onSuccess(JSONObject result) {
final JSONObject finalResult = result;
try {
if (result != null && result.has("success") && result.getBoolean("success")) {
new AsyncDeleteUnreadMessagesList(context, unreadMessagesArrayList, new Callback() {
#Override
public void onCallbackCompleted() {
try {
ArrayList<com.app.amber.internet.DATABASE_OPERATIONS.schema.message> messagesToStore = new ArrayList<>();
JSONObject result = finalResult.getJSONObject("data");
JSONObject last_messages = result.getJSONObject("last_messages");
new AsyncUpdateLastMessage(context, last_messages, true, new Callback() {
#Override
public void onCallbackCompleted() {
try {
JSONArray json_messages_to_store = result.getJSONArray("messages");
JSONArray json_evetns_type_1 = result.getJSONArray("eventsType1");
JSONArray json_evetns_type_2 = result.getJSONArray("eventsType2");
for (int i = 0; i < json_messages_to_store.length(); i++) {
JSONObject data = json_messages_to_store.getJSONObject(i);
String id = data.getString("id"),
sender_id = data.getString("sender_id"),
receiver_id = data.getString("receiver_id"),
msg = data.getString("msg"),
type = data.getString("type"),
path = data.getString("path"),
download_status = data.getString("download"),
group_users = data.getString("group_users"),
group_message_status = data.getString("group_message_status");
boolean is_sender = false;
long data_created = data.getLong("date_created");
int is_read = 0;
com.app.amber.internet.DATABASE_OPERATIONS.schema.message message =
new com.app.amber.internet.DATABASE_OPERATIONS.schema.message(id, sender_id, receiver_id, msg, type, path, is_sender, data_created,
is_read, download_status, sender_id, group_users, group_message_status);
messagesToStore.add(message);
}
ArrayList<String> messageIdsType1 = new ArrayList<>();
ArrayList<String> messageIdsType2 = new ArrayList<>();
for (int i = 0; i < json_evetns_type_1.length(); i++) {
messageIdsType1.add(json_evetns_type_1.getJSONObject(i).getString("id"));
}
for (int i = 0; i < json_evetns_type_2.length(); i++) {
messageIdsType2.add(json_evetns_type_2.getJSONObject(i).getString("id"));
}
new AsyncStoreOldMessagesLocally(context, messagesToStore, new Callback() {
#Override
public void onCallbackCompleted() {
new AsyncUpdateMessageStatus(context, messageIdsType1, 1, new Callback() {
#Override
public void onCallbackCompleted() {
new AsyncUpdateMessageStatus(context, messageIdsType2, 2, new Callback() {
#Override
public void onCallbackCompleted() {
new AsyncUpdateMessageStatusList(context, messageArrayListNotSync, new Callback() {
#Override
public void onCallbackCompleted() {
sendCallBack();
}
}).execute();
}
}).execute();
}
}).execute();
}
}).execute();
} catch (Exception e) {
System.out.println("Exception occurred while getting data from data JSONObject received from service: " + e.toString());
e.printStackTrace();
sendCallBack();
}
}
}).execute();
} catch (Exception e) {
System.out.println("Exception occurred while parsing data JSONObject received from service: " + e.toString());
e.printStackTrace();
sendCallBack();
}
}
}).execute();
} else {
sendCallBack();
}
} catch (Exception e) {
System.out.println("Exception occurred while parsing webservice result: " + e.toString());
sendCallBack();
}
}
});
} catch (Exception e) {
System.out.println("exception occurred while parsing messaging lists: " + e.toString());
sendCallBack();
}
return null;
}
private void sendCallBack() {
if (callback != null) {
callback.onSuccess();
}
}
#Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
}
}
"WorkManager startWork() never calls when constraints are met"
"It calls only one time at the start where I register it."
The ListenableWorker can be recreated in some situations, a new instance of ListenableWorker with the same first ListenableWorker.id. But for it be recreated, it can't be finished. Here are some situations:
Some of the constraints do not matches anymore and it matches again
System was rebooted
Now here are some situations where it will be finished:
Some Exception was raised without treatment
completer.set(Result.success()) was called
completer.set(Result.failure()) was called
There are some situations in your code that the worker can be finished.
There are lots of calls to AsyncSyncData.sendCallBack, which can causes the call of completer.set(Result.success()) on the ListenableWorker instance. If it happens the ListenableWorker completes the job, so it will not be recreated anymore.
"I want to WorkManager startWork() to be called every time the user connects to the internet through wifi or 3g/4g/5g."
The WorkManager alone won't create a new instance of the ListenableWork every time the user connects to Internet. The WorkManager is a API to schedule tasks, and the constraints defined in the ListenableWork are used to not start it while them are not matched, after the ListenableWork finishes, how was discussed above, this task is finished, so no more to do.
If you want to listen to some connectivity changes, you should use ConnectivityManager.registerNetworkCallback and then when the user connects to, you do what you want. Here are some examples that could help you
to do it.
I am looking for a solution for uploading data to Firebase without having the user wait for the data to upload, so that the user can use the app in offline mode.
Let's suppose that the app is about places. In this app, the user can upload an image and an object containing address, city, state, country, latitude, longitude, description, etc. Let's say a big POJO.
Firebase Realtime Database and Firebase Firestore can wait for (I do not know for how long) a stable internet connection to send the data. But Firebase Storage do not have this feature.
So I've found WorkManager. It seemed to solve the problem, but I had to serialize my POJO into small primitive variable types in order to send the POJO to Worker class.
The result I want to achieve is:
1) upload image to Firebase Storage
2) download URL of the image
3) send the POJO to Firebase Firestore with the ImageUrl in it.
QUESTIONS
1) Is WorkManager best suited for this kind of purpose?
2) How many times can an user trigger this background job without causing any issue to the app in offline mode?
3) How to propperly send the POJO to the Worker class?
Here is what I've done so far:
Get pushKey for the new place, start the background job and keep navigating through activities:
savePlaceData.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
DocumentReference docRef = DatabaseRouter.getPlaceCollectionRef().document();
String key = docRef.getId();
uploadPlaceDataInBackground(key)
Intent intent = new Intent(PlaceActivity.this, OtherActivity.class);
startActivity(intent);
}
});
Set the request for the background job:
private void uploadPlaceDataInBackground(String placeKey) {
// TESTING WORKMANAGER FOR UPLOADING IMAGES TO FIREBASE STORAGE
// Create a Constraints object that defines when the task should run
Constraints constraints = new Constraints.Builder()
.setRequiredNetworkType(NetworkType.CONNECTED)
.build();
// Passing data to the worker class
Data.Builder uploadBuilder = new Data.Builder();
uploadBuilder.putString("image_uri", placeImageUri.toString());
uploadBuilder.putString("image_pushkey", placeKey);
Data ImageUriInputData = uploadBuilder.build();
// ...then create a OneTimeWorkRequest that uses those constraints
OneTimeWorkRequest uploadWorkRequest = new OneTimeWorkRequest
.Builder(UploadImageWorker.class)
.setConstraints(constraints)
.setInputData(ImageUriInputData)
.build();
OneTimeWorkRequest downloadWorkRequest = new OneTimeWorkRequest
.Builder(DownloadImageUrlWorker.class)
.setConstraints(constraints)
.build();
// Converting placeObject into Map
Data.Builder uploadPlaceBuilder = new Data.Builder();
Map<String, Object> placeMap = convertPlaceObjectIntoMap();
uploadPlaceBuilder.putAll(placeMap);
Data placeInfoInputData = uploadPlaceBuilder.build();
OneTimeWorkRequest uploadPlaceWorkRequest = new OneTimeWorkRequest
.Builder(UploadPlaceWorker.class)
.setConstraints(constraints)
.setInputData(placeInfoInputData)
.build();
// Execute and Manage the background service
WorkManager workManager = WorkManager.getInstance(getActivity());
workManager.beginWith(uploadWorkRequest)
.then(downloadWorkRequest)
.then(uploadPlaceWorkRequest)
.enqueue();
}
Below are the Worker classes:
public class UploadImageWorker extends Worker {
public UploadImageWorker(#NonNull Context context, #NonNull WorkerParameters workerParams) {
super(context, workerParams);
}
#NonNull
#Override
public Result doWork() {
String imageUriInput = getInputData().getString("image_uri");
String imagePushKey = getInputData().getString("image_pushkey");
final Result[] result = {Result.retry()};
CountDownLatch countDownLatch = new CountDownLatch(1);
StorageReference storageRef = DatabaseRouter.getPlaceStorageRef(imagePushKey).child(imagePushKey+".jpg");
storageRef.putFile(Uri.parse(imageUriInput)).addOnCompleteListener(new OnCompleteListener<UploadTask.TaskSnapshot>() {
#Override
public void onComplete(#NonNull Task<UploadTask.TaskSnapshot> task) {
if (task.isSuccessful()) {
result[0] = Result.success(getInputData());
} else {
Log.i(TAG, "onComplete: image NOT uploaded - RETRYING");
result[0] = Result.retry();
}
countDownLatch.countDown();
}
});
try {
countDownLatch.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
return result[0];
}
}
public class DownloadImageUrlWorker extends Worker {
public DownloadImageUrlWorker(#NonNull Context context, #NonNull WorkerParameters workerParams) {
super(context, workerParams);
}
#NonNull
#Override
public Result doWork() {
String imageUriInput = getInputData().getString("image_uri");
String imagePushKey = getInputData().getString("image_pushkey");
final Result[] result = {Result.retry()};
CountDownLatch countDownLatch = new CountDownLatch(1);
StorageReference storageRef = DatabaseRouter.getPlaceStorageRef(imagePushKey).child(imagePushKey+".jpg");
storageRef.getDownloadUrl().addOnSuccessListener(new OnSuccessListener<Uri>() {
#Override
public void onSuccess(Uri uri) {
String imageUrl = uri.toString();
Data.Builder outputBuilder = new Data.Builder();
outputBuilder.putString("image_url", imageUrl);
outputBuilder.putString("image_pushkey", imagePushKey);
Data outputData = outputBuilder.build();
result[0] = Result.success(outputData);
countDownLatch.countDown();
}
}).addOnFailureListener(new OnFailureListener() {
#Override
public void onFailure(#NonNull Exception e) {
Log.i(TAG, "onFailure: imageUrl NOT downloaded - RETRYING");
result[0] = Result.retry();
countDownLatch.countDown();
}
});
try {
countDownLatch.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
return result[0];
}
}
public class UploadPlaceWorker extends Worker {
public UploadPlaceWorker(#NonNull Context context, #NonNull WorkerParameters workerParams) {
super(context, workerParams);
}
#NonNull
#Override
public Result doWork() {
String imageUrl = getInputData().getString("image_url");
String imagePushKey = getInputData().getString("image_pushkey");
Map<String, Object> placeObject = getInputData().getKeyValueMap();
PlaceModel placeModel = convertMapIntoPlaceObject(placeObject, imageUrl, imagePushKey);
final Result[] result = {Result.retry()};
CountDownLatch countDownLatch = new CountDownLatch(1);
DocumentReference docRef = DatabaseRouter.getPlaceCollectionRef().document(imagePushKey);
docRef.set(placeModel).addOnCompleteListener(new OnCompleteListener<Void>() {
#Override
public void onComplete(#NonNull Task<Void> task) {
if (task.isSuccessful()) {
result[0] = Result.success();
} else {
Log.i(TAG, "onComplete: place NOT uploaded - RETRYING");
result[0] = Result.retry();
}
countDownLatch.countDown();
}
});
try {
countDownLatch.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
return result[0];
}
private PlaceModel convertMapIntoPlaceObject(Map<String, Object> placeMap, String imageUrl, String placeKey) {
PlaceModel place = new PlaceModel();
place.setAddress(placeMap.get("a").toString());
place.setCity(placeMap.get("b").toString());
place.setCountry(placeMap.get("c").toString());
place.setDistrict(placeMap.get("d").toString());
place.setG(placeMap.get("e").toString());
place.setId(placeMap.get("f").toString());
place.setImage(imageUrl);
place.setKey(placeKey);
GeoPoint geoPoint = new GeoPoint((Double) placeMap.get("h"), (Double) placeMap.get("i"));
place.setL(geoPoint);
place.setDescription(placeMap.get("j").toString());
return place;
}
}
I appreciate any help!
I download a high amount of data from API and want to make it efficient so I get first 100 record in one asyncTask and then in another asyncTask get another several thousands(in 500 hundred portions) The loadListAsynchronously(); looks identicall as loadData function without content,progress,loadContent(); function but this functions are not the problem - without loadListAsynchronously(); app runs smoothly after frezee when download first data. I tried add transaction but that does not help me.
private void loadData() {
DottedProgressBar progressBar = (DottedProgressBar) findViewById(R.id.loadIngDots);
progressBar.startProgress();
content = (LinearLayout)findViewById(R.id.activity_main) ;
progress = (RelativeLayout) findViewById(R.id.progressPage) ;
AsyncTask<String, Void, String> read =new AsyncTask<String, Void, String>() {
SharedPreferences keyValues;
#Override
protected void onPreExecute() {
content.setVisibility(View.GONE);
keyValues = getSharedPreferences(Settings.MODEL_LAST_CALL, Context.MODE_PRIVATE);
DisplayMetrics displaymetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
height = displaymetrics.heightPixels;
width = displaymetrics.widthPixels;
super.onPreExecute();
}
#Override
protected String doInBackground(String... params) {
modelList = new ArrayList<>();
Map<String,String> options= new HashMap<>();
options.put("limit",String.valueOf(AMOUNT_OF_LOADED_modelS));
ApiHelper.getModelWithParams(new Callback<ModelApiEnvelope>() {
#Override
public void onResponse(Call<ModelApiEnvelope> call, Response<ModelApiEnvelope> response) {
Log.i(TAG,"First call model Get response");
final ModelApiEnvelope envelope = response.body();
if(envelope==null)
Toast.makeText(MainActivity.this,getString(R.string.server_down_explanation),Toast.LENGTH_SHORT).show();
else{
try {
final Dao<Model,Integer> modelDAO = getHelper().getmodelDAO();
final Dao<Submodel,Integer> submodelDAO=getHelper().getsubmodelDAO();
TransactionManager.callInTransaction(getHelper().getConnectionSource(),
new Callable<Void>() {
public Void call() throws Exception {
modelList=envelope.getData();
Log.i(TAG,"LoadData loop Start");
for( final model m: modelList){
m.setLogo(m.getLogo()+"?width="+width/2+"&height="+height);
m.setLanguage(m.getLanguage().substring(0,2));
if(m.getLanguage().equals("uk"))
m.setLanguage("ua");
if(m.getsubmodels().size()!=0){
for(final submodel e: m.getsubmodels()){
e.setLanguage(m.getLanguage());
submodelDAO.createOrUpdate(e);
}
}
try {
modelDAO.createOrUpdate(m);
}catch (SQLException e) {e.printStackTrace();}
}
return null;}
});
if(envelope.getData().isEmpty()){
SharedPreferences.Editor editor = sharedPreferences.edit();
long time = System.currentTimeMillis();
editor.putString(Settings.model_LAST_CALL , Long.toString(time));
editor.apply();
}
else
loadListAsynchronously();
} catch (SQLException e) {
Log.i(TAG," message "+e.getMessage()) ; e.printStackTrace();
}}
loadContent();
content.setVisibility(View.VISIBLE);
progress.setVisibility(View.GONE);
}
#Override
public void onFailure(Call<modelApiEnvelope> call, Throwable t) {
Log.i(TAG,"ERROR"+ t.getMessage());
Toast.makeText(MainActivity.this,getString(R.string.server_down_explanation),Toast.LENGTH_LONG).show();
loadContent();
}
},MainActivity.this,options, keyValues.getString(lang,"0"));
return null;
}
#Override
protected void onProgressUpdate(Void... values) {
super.onProgressUpdate(values);
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
}
};
read.execute();
}
UPDATE: Method Trace added
UPDATE 2: Removing the transaction solve my problem. It seems that the making transaction for thousands saveings into database freeze Ui.
Callback in Retrofit1 and AsyncTask are not compatible. You have to modify your API interface from something like this :
public interface Api {
void getModelWithParams(Callback<Something> callback);
}
To this :
public interface Api {
Something getModelWithParams();
}
Then Retrofit will not provide async execution support and you can execute that row method inside AsyncTask.doInBackground method.
Other option is to stay with that interface definition and just call Retrofit method directly (without AsyncTask wrapping). The question is if your further logic is not heavy, because onResponse will be executed on UI Thread which cause your freezes and in general is root cause of your problem.
my below sample code work fine without any some problem, this sample code can cache received data from url and using that when device doesnt have any internet connection.
but this code have a big deficiency, it is when device have internet connection i cant recache and get newest data from internet and recache again until device doesnt have connection, some data can be image or json array or json object
public class MainActivity extends AppCompatActivity {
private final Context mContext = this;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final TextView textView = (TextView) findViewById(R.id.textView);
RequestQueue queue = Volley.newRequestQueue(this);
String url = "http://192.168.1.2/test";
CacheRequest cacheRequest =
new CacheRequest(0, url, new Response.Listener<NetworkResponse>() {
#Override
public void onResponse(NetworkResponse response) {
try {
final String jsonString = new String(response.data,
HttpHeaderParser.parseCharset(response.headers));
JSONObject jsonObject = new JSONObject(jsonString);
textView.setText(jsonObject.toString(5));
Log.e('OutPut',jsonObject.toString());
} catch (UnsupportedEncodingException | JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(mContext, "onErrorResponse:\n\n" + error.toString(), Toast.LENGTH_SHORT).show();
}
});
queue.add(cacheRequest);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
private class CacheRequest extends Request<NetworkResponse> {
private final Response.Listener<NetworkResponse> mListener;
private final Response.ErrorListener mErrorListener;
public CacheRequest(int method, String url, Response.Listener<NetworkResponse> listener, Response.ErrorListener errorListener) {
super(method, url, errorListener);
this.mListener = listener;
this.mErrorListener = errorListener;
}
#Override
protected Response<NetworkResponse> parseNetworkResponse(NetworkResponse response) {
Cache.Entry cacheEntry = HttpHeaderParser.parseCacheHeaders(response);
if (cacheEntry == null) {
cacheEntry = new Cache.Entry();
}
final long cacheHitButRefreshed = 3 * 60 * 1000; // in 3 minutes cache will be hit, but also refreshed on background
final long cacheExpired = 24 * 60 * 60 * 1000; // in 24 hours this cache entry expires completely
long now = System.currentTimeMillis();
final long softExpire = now + cacheHitButRefreshed;
final long ttl = now + cacheExpired;
cacheEntry.data = response.data;
cacheEntry.softTtl = softExpire;
cacheEntry.ttl = ttl;
String headerValue;
headerValue = response.headers.get("Date");
if (headerValue != null) {
cacheEntry.serverDate = HttpHeaderParser.parseDateAsEpoch(headerValue);
}
headerValue = response.headers.get("Last-Modified");
if (headerValue != null) {
cacheEntry.lastModified = HttpHeaderParser.parseDateAsEpoch(headerValue);
}
cacheEntry.responseHeaders = response.headers;
return Response.success(response, cacheEntry);
}
#Override
protected void deliverResponse(NetworkResponse response) {
mListener.onResponse(response);
}
#Override
protected VolleyError parseNetworkError(VolleyError volleyError) {
return super.parseNetworkError(volleyError);
}
#Override
public void deliverError(VolleyError error) {
mErrorListener.onErrorResponse(error);
}
}
}
It will cache only once because onCreate method is called once the app created..
most suitable solution would be this:
You need to have a Service which uses AlarmManager for, say, every 5 minutes to trigger itself. And in this service you can cache the newest data in the background, of course for smaller time unit, more battery will be consumed.
update for cache resizing
RequestQueue volleyQueue = Volley.newRequestQueue(this);
DiskBasedCache cache = new DiskBasedCache(getCacheDir(), 16 * 1024 * 1024);
volleyQueue = new RequestQueue(cache, new BasicNetwork(new HurlStack()));
volleyQueue.start();
according to that discussion volley's cache can be manipulated, but when it gets full, automatically replaces new data with the old one so, cache size is not the focus right now.
update for cache cleaning
mahdi, according to official link of google volley's Cache class, there is a method called invalidate(), which invalidates the cached data, and next time volley checks if data was valid and update it.
you can appereantly delete cache for every 30 minutes according to this discussion:
serverDate: AppController.getInstance().getRequestQueue().getCache().get(url).serverDate
getMinutesDifference is method calculates time passed, can be found on reference link.
Calendar calendar = Calendar.getInstance();
long serverDate = AppController.getInstance().getRequestQueue().getCache().get(url).serverDate;
if(getMinutesDifference(serverDate, calendar.getTimeInMillis()) >=30)
{
AppController.getInstance().getRequestQueue().getCache().invalidate(url, true);
}
You can first check your Internet connection, if you have connection you can clear the cache and reload
ConnectivityManager connMgr = (ConnectivityManager) getActivity().getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
if (networkInfo != null && networkInfo.isConnected()) {
MySocialMediaSingleton.getInstance(getContext()).getRequestQueue().getCache().invalidate("http://server/json.php?page=1", true);
}
//Calling again method to get data to fetch data
getData();
if (isConnected()) {
Event eInstance = new Event();
theEvents = eInstance.downloadEvents(eventsNightlife, getActivity());
rAdapter = new RecyclerAdapter(theEvents);
recyclerView.setAdapter(rAdapter);
progrsBar.setVisibility(View.GONE);
....
This is part of the code that runs at "onCreateView". The method downloadEvents uses Volley to download JSON data, extract it and return a list of items (theEvents). Now when my app starts, the recycler view is empty. If I go to my home screen out of the app and then run my app again, this time the data sometimes gets downloaded.
I debugged step by step, and at first launch (i mean when the app is not just resuming), theEvents is empty, so the download didn't return or manage to return anything...
Suggestions on how to execute things before the UI has been shown to the user or what actually needs to be done to approach this task better?
Also, I use a swipeRefreshLayout and at its onRefresh method I do:
public void onRefresh() {
Event eInstance = new Event();
theEvents = eInstance.downloadEvents(eventsNightlife, getActivity());
rAdapter.notifyDataSetChanged();
swipeRefreshLayout.setRefreshing(false);
}
but it doesn't work. I also tried to
rAdapter = new RecyclerAdapter(theEvents);
rAdapter.notifyDataSetChanged();
recyclerView.swapAdapter(rAdapter, false);
still not working.
EDIT: My downloadEvents method implementing Volley:
public List<Event> downloadEvents(String urlService, Context context) {
eventsList = new ArrayList<>();
RequestQueue requestQueue = Volley.newRequestQueue(context);
JsonArrayRequest jsonArrayRequest = new JsonArrayRequest
(Request.Method.GET, urlService, null, new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray response) {
try {
String durationStr = null;
for (int i = 0; i < response.length(); i++) {
JSONObject eventJson = response.getJSONObject(i);
String title = eventJson.getString("EventTitle");
String body = eventJson.getString("EventBody");
String date = eventJson.getString("EventDate");
String time = eventJson.getString("EventTime");
int duration = Integer.parseInt(eventJson.getString("EventDuration"));
if (duration > 60) {
durationStr = "Duration: " + duration / 60 + " h";
} else if (duration < 60) {
durationStr = "Duration: " + duration + " m";
}
String place = eventJson.getString("EventPlace");
String organ = eventJson.getString("Organization");
Event event = new Event(title, body, date, time, durationStr, place, organ);
eventsList.add(event);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.e("VOLLEY ERROR", "" + error);
}
}
);
requestQueue.add(jsonArrayRequest);
return eventsList;
}
You can use EventBus for your purpose that is a simple and truth way.
Here, i write an example for how to use EventBus with volley.
Consider that i want to download some data.
This is the class that my download methods is inside it (you can add more methods to it in the future):
Im used volley to download my data:
// Download methods is inside volley
public class MyDownloader{
public static void downloadData(){
DownloadDataEvent dlDataEvent=new DownloadDataEvent();
List<String> myResult=new ArrayList<>();
...
#Override
public void onResponse(JSONArray response) {
super.onResponse(response);
if(respone!=null){
// Do what i want with my received data
dlDataEvent.setData(response);
}
// Post my event by EventBus
EventBus.getDefault().post(dlDataEvent);
...
}
}
}
This is my event:
public class DownloadDataEvent{
private JSONArray mData;
public void setData(JSONArray data){
mData=data;
}
public JSONArray setData(){
return mData;
}
}
Now i want to use my downloadData() method inside my MainActivity:
(I called my downloadData method inside onCreate.)
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
...
// I have to register this class for EventBus subscriber:
if(!EventBus.getDefault().isRegister(this)){
EventBus.getDefault().registerSticky(this);
}
// Call my downloadData method
if(isConnected()){
MyDownloader.downloadData();
}
}
// And for receive the data through EventBus, i have to create a
// method (subscriber) in this template:
public void onEventMainThread(DownloadDataEvent downloadDataEvent){
JSONArray result=downloadDataEvent.getData();
// Do what i want with my received data
}
}
you can create more than one subscriber every where you want to use received data.
I passed JSONArray to my DownloadDataEvent that it is not good. you can deserialize your received data and pass it to your DownloadDataEvent.
I used Volley to download data
Maybe my descriptions were confusing, but EventBus is a well-known library and is very easy to use.