Non UI thread modifying UI component - java

I have a thread that needs to be receiving data all the time from the network and I want this data to be displayed to an EditText object.
Obviously, I can't access the UI EditText from within my receiving thread; what I read is that I can use AsyncTask but reading the example in Painless Threading it seems to me that I have to be done with receiving the data before I can be able to post the results to the UI component.
I can't use post or postDelayed as both will be run over the UI thread and I can't block the UI to receive the data; I need to keep receiving the data all the time.
What other options do I have?

Use LocalBroadcastManager, your Activity containing TextView will start listening for broadcast:
public class MyActivity extends Activity {
private TextView mTextView;
BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getStringExtra("actionType");
if(action.equals("updateTextView")){
mTextView.setText("whatever you want to set");
}
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//Start listening, you can put it on onResume too
LocalBroadcastManager.getInstance(this).registerReceiver(broadcastReceiver, new IntentFilter(MyActivity.class.getSimpleName()));
mTextView = (TextView) findViewById(R.id.something);
}
}
So whenever your Thread receive something that needs to update the screen, call this:
Intent intent = new Intent(MyActivity.class.getSimpleName());
intent.putExtra("actionType", "updateTextView");
// Once this is called, your broadcast receiver in MyActivity should receive it and start processing
LocalBroadcastManager.getInstance(context).sendBroadcast(intent);
Also remember to unregister it in onDestroy or onPause.
*side note: you need to import android support v4 library, and you can pass simple String or object over by intent using Intent.putExtra("","") and Inteng.getExtra("");

Another way is to implement a data listener interface.
public interface DataListener{
void onUpdateData(MyData data);
}
You activities that contain the UI components that need to be updated will implement this interface. It will specify what need to do with updated data.
You may want to keep all instances these data listener interface somewhere in your app.
I assume that you have a different thread to handle network sending/receiving actions. On receiving data, you just call:
dataListenerInstance.onUpdateData(data)
Then it will activate the handler that you have implemented in your activity.

In MainActivity call AsyncTask but make #Override method onPostExecute(..)
public class MainActivity extends ActionBarActivity{
...
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if(Utils.isNetworkAvailable(this)) {
DownloadFileFromURL downloader = new DownloadFileFromURL(){
#Override
protected void onPostExecute(Integer file_content) {
onCompleteLoad();
}
};
downloader.execute(new String[]{file_url, fileName});
...
onCompleteLoad(); - will be call in UI thread of MainActivity. You don't need even implements Interface!
Secon way more suitable for server solutions, but can also be used on the client it is Callable
public class DoGetSize implements Callable<Integer> {
private final String file_url;
private int lenghtOfFile = -1;
public DoGetSize(String file_url) {
this.file_url = file_url;
}
public Integer call() {
try {
URL url = new URL(file_url);
URLConnection connection = url.openConnection();
connection.connect();
lenghtOfFile = connection.getContentLength();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return lenghtOfFile;
}
}
And call this like:
FutureTask<Integer> task = new FutureTask(new DoGetSize(file_url));
ExecutorService es = Executors.newSingleThreadExecutor();
es.submit (task);
try {
Integer result = task.get();
File file = new File(fileName);
if(file.length() != result.intValue()) {
// Do something
...
}
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
You can send and receive any object in such a way
Full example see on github: https://github.com/app-z/OffLineShop/blob/master/app/src/main/java/net/appz/offlineshop/offlineshop/MainActivity.java

You can do this using a simple delegation.
class NonUIThread {
private NonUIThreadDelegate delegate; //NonUIThreadDelegate can be an interface or an object that has access to your UI thread like an Activity
public void setDelegate(NonUIThreadDelegate delegate) {
this.delegate = delegate;
}
private void doSomthing() {
//do something and at the end:
delegate.someMethodThatUpdatesThatComponent();
}
}
class TheUIThread implements NonUIThreadDelegate /*assuming you've decided to make NonUIThreadDelegate an interface*/ { // the "delegator"
/*
your code
*/
private void initiateNonUIThread() {
NonUIThread nonUIThread;
/*do whatever needed*/
nonUIThread.setDelegate(this);
nonUIThread.start();
}
public void someMethodThatUpdatesThatComponent() { //will be called by the non ui thread
//update the UI
}
}
It's explained a little better (of course using AsincTask) in here: Simple Delegation Pattern in Android

Related

Running CountDownTimer inside AsyncTask throws java.lang.RuntimeException - Looper.prepare()

I have a .lrc file and I need to go over every line with a CountDownTimer. I have tried using AsyncTask to do so but I get the error:
Caused by: java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
On line new CountDownTimer... I tried doing it with runnable but I still get the same error. My goal is to get it to go over every line in .lrc file which looks like this:
[00:04.15]Help me, it's like the walls are caving in
[00:10.46]Sometimes I feel like giving up
[00:13.63]But I just can't
...
I am not sure how efficient it is to do it the way I am trying to do. I am thinking of going through every line in the doInBackground(). If there is a better way to do it then let me know. But to begin with, why am I getting the EXCEPTION ?
Just to note.. I have simplified the code as much as I could so it would be easier to understand what I am trying to do.
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
MyView myView = new
myView.play();
}
}
public class MyView{
public void play() {
new CustomAsync().execute();
}
}
class CustomAsync extends AsyncTask<Lyric, Void, Void> {
protected Void doInBackground(Lyric... param) {
startLyricCountDownTimer(param);
return null;
}
protected void onPostExecute(Void param) {
//Print Toast or open dialog
}
private void startLyricCountDownTimer(Lyric lyric){
new CountDownTimer(30000, 10) { //This is where it throws the error
public void onTick(long millisUntilFinished) {
//Do the thing
}
public void onFinish() {
}
}.start();
}
}
EDIT
Is it better to go with the AsyncTask and do like Son Truong suggested or to use the following code for each and every lrc line?
new Handler(Looper.getMainLooper()).post(new Runnable() {
#Override
public void run() {
new CountDownTimer(millisInFuture,countDownInterval) {
#Override
public void onTick(
CountDownTimer uses a Handler to post messages to a Message Queue of a Thread which has a Looper. onTick and onFinish will be called on which thread based on where you create CountDownTimer instance.
In your case because you create CountDownTimer instance in doInBackground method of AsyncTask so these two methods will be call on AsyncTask thread.
In constructor of CountDownTimer, it will create Handler instance as well. The Handler will check whether or not current thread has a Looper, if not it will throw a RuntimeException with message.
Can't create handler inside thread that has not called
Looper.prepare()
Because AsyncTask uses a thread which has no Looper, that why your app crashes.
My suggestion is in doInBackground method you open a connection to .lrc file and read each line, for each line read, use runOnUIThread to send the line to UI thread (then you can process the line read there by display a Toast on screen, etc).
Update: I will demo how to read line by line from a file then display it on a text view each 3 seconds.
First write a class which read from an inputstream line by line
static class ReadLyricTask extends AsyncTask<InputStream, String, Void> {
WeakReference<MainActivity> mMainActivity;
ReadLyricTask(MainActivity activity) {
mMainActivity = new WeakReference<>(activity);
}
#Override
protected Void doInBackground(InputStream... inputStreams) {
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStreams[0]));
String line;
try {
while ((line = reader.readLine()) != null) {
publishProgress(line);
}
} catch (IOException e) {
// Do nothing.
} finally {
try {
inputStreams[0].close();
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
#Override
protected void onProgressUpdate(String... values) {
MainActivity activity = mMainActivity.get();
if (activity != null) {
activity.displayLyricLineOnTextView(values[0]);
}
}
}
Then just use it in MainActivity
public class MainActivity extends AppCompatActivity {
private static final int UPDATE_LYRIC_TEXT_INTERVAL = 3000; // Change lyric text each 3 seconds.
private int mCurrentInterval = 0;
private TextView mLyricTextView;
private Handler mHandler = new Handler();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mLyricTextView = findViewById(R.id.lyricText);
// I put a file named lyric.lrc in raw folder, for your case just open an input stream from a file.
InputStream inputStream = getResources().openRawResource(R.raw.lyric);
new ReadLyricTask(this).execute(inputStream);
}
private void displayLyricLineOnTextView(final String lyricLine) {
mHandler.postDelayed(new Runnable() {
#Override
public void run() {
mLyricTextView.setText(lyricLine);
}
}, mCurrentInterval);
mCurrentInterval += UPDATE_LYRIC_TEXT_INTERVAL;
}
}
CountDownTimer runs in separate thread and no need of asynctask to run a timer.Best solution would be create a service and make service to trigger a timer.
As timer run on non ui thread, while updating ui make sure you update from UI thread.You could use UI handler or runOnUithread method to update view.

How do I get a string from a thread or return a String form a Thread?

Im using a webservice that get a data and stores in a String. I need to use this String but I cant take it. Global variables don't work in Threads. I'm using a traditional Thread new Thread() { public void run() {.
Example of AsyncTask:
public class Task extends AsyncTask<Params, Progress, String> {
// are you know how to use generic types?
protected String doInBackground(Params[] params){
// this code will run in seperate thread
String resultString;
return resultString;
}
protected void onPostExecute(String resultString){
// this code will call on main thread (UI Thread) in this thread you can update UI e.g. textView.setText(resultString);
}
}
Use LocalBroadcastManager to send and receive data.
This way you can avoid memory leak issues.
Here is code for activity
public class YourActivity extends Activity {
private void signal(){
LocalBroadcastManager.getInstance(YourActivity.this).registerReceiver(receiver, new IntentFilter("Your action name"));
Intent yourAction = new Intent(YourActivity.this, YourIntentService.class);
String string = "someData";
yourAction .putExtra("KEY_WITH_URL", string);
startService(yourAction);
}
private BroadcastReceiver receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String string = intent.getStringExtra("KEY_WITH_ANSWER");
//Do your code
}
};
}
Here code for thread which download String or whatever
public class YourIntentService extends IntentService {
#Override
protected void onHandleIntent(Intent intent) {
// Download here
Intent complete = new Intent ("Your action name");
complete.putExtra("KEY_WITH_ANSWER", stringToReturn);
LocalBroadcastManager.getInstance(YourIntentService.this).sendBroadcast(complete);
}
}
You can use Thread instead of IntentService.
use a Handler created from the main thread. Then pass your data throuh it
use a weak reference of your activity in your thread; this way you can call directly the main thread - Activity.runOnUiThread(Runnable)
...
Activity activity = activityWeakReference.get();
if (activity != null && !activity.isFinishing() && !activity.isDestroyed()) {
activity.runOnUiThread(new Runnable() {
#Override
public void run()
{
// you are in main thread, pass your data
}
});
}
You can use Async task:
private class Whatever extends AsyncTask<Void, Void, String> {
protected String doInBackground(Void... void) {
// do your webservice processing
return your_string;
}
protected void onPostExecute(String result) {
// Retrieves the string in the UI thread
}
}

Android communication between main thread and other thread

I want to change dynamically the text of a textview, but I will need the same logic if I want to make a game thread, so I need to make the communication between the main one and the second one.
I have the files :
MainActivity
public class MainActivity extends ActionBarActivity {
public static Handler mHandler;
Runnable thread = new SampleThread();
TextView txt1 = (TextView) findViewById(R.id.txt1);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ActionBar actionBar = getSupportActionBar();
actionBar.hide();
//hiding status bar
if (Build.VERSION.SDK_INT < 16) {
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
} else {
View decorView = getWindow().getDecorView();
int uiOptions = View.SYSTEM_UI_FLAG_FULLSCREEN;
decorView.setSystemUiVisibility(uiOptions);
}
setContentView(R.layout.activity_main);
mHandler = new Handler() {
public void handleMessage(Message msg) {
// process incoming messages here
// i want to change the text of txt1 here
}
};
new Thread(thread).start();
}
}
SampleThread
package com.example.katsar0v.myapplication;
import android.util.Log;
/**
* Created by Katsar0v on 1/21/2015.
*/
public class SampleThread implements Runnable {
#Override
public void run() {
int two = 0;
while(two<10) {
two++;
try {
Thread.sleep(1000);
//instead of logging, i want to send the text to main UI
Log.d("MSG", String.valueOf(two + "sec"));
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
The problem I see is, how do I change the text with the handler, when my thread is in another file? Or should I make the second class static within the first one (and what should I do when the code gets really long, it can't be all in one file)?
You could implement a custom Interface in order to handle it from your main activity.
On your SampleThread:
public interface TextViewChangeListener
{
public void onTextViewChanged(String newName);
}
TextViewChangeListener mListener;
Then call mListener.onTextViewChanged(String newName) wherever you want to have the new name in your TextView. Remember to initialize mListener with an instance of your MainActivity first, otherwise you will get a null pointer exception. You can do that either in the constructor of SampleThread or by creating a method for the purpose.
In your activity you should implement SampleThread.TextViewChangeListener and override the onTextViewChanged.
#Override
public void onTextViewChanged(String newName)
{
//MyTextView.setText(newName);
}
Edit: untested code:
MainActivity:
public class MainActivity extends ActionBarActivity implements SampleThread.TextViewChangeListener {
#Override
public void onTextViewChanged(Message msg)
{
// process incoming messages here
// i want to change the text of txt1 here
}
public static Handler mHandler;
Runnable thread = new SampleThread(this);
TextView txt1 = (TextView) findViewById(R.id.txt1);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ActionBar actionBar = getSupportActionBar();
actionBar.hide();
//hiding status bar
if (Build.VERSION.SDK_INT < 16) {
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
} else {
View decorView = getWindow().getDecorView();
int uiOptions = View.SYSTEM_UI_FLAG_FULLSCREEN;
decorView.setSystemUiVisibility(uiOptions);
}
setContentView(R.layout.activity_main);
new Thread(thread).start();
}
}
SampleThread:
package com.example.katsar0v.myapplication;
import android.util.Log;
/**
* Created by Katsar0v on 1/21/2015.
*/
public class SampleThread implements Runnable
{
public interface TextViewChangeListener
{
public void onTextViewChanged(Message msg);
}
public SampleThread(TextViewChangeListener mListener)
{
this.mListener = mListener;
}
TextViewChangeListener mListener;
#Override
public void run() {
int two = 0;
while(two<10) {
two++;
try {
Thread.sleep(1000);
mListener.onTextViewChanged(String.valueOf(two + "sec"));
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
Let me know if that helped.
You can find some examples in Grafika, which does a lot of work off the UI thread. For example, TextureFromCameraActivity has a pair of handlers, one for the UI thread, one for the renderer thread. In onResume() you can see the main thread passing its handler to the renderer through a constructor, then retrieving the renderer thread's handler with a method call.
ContinuousCaptureActivity has a slightly different approach, using a Handler that also implements a callback interface. The handler object is passed to the CircularEncoder constructor as an interface instance. The public callback methods use the Handler internally.
The only tricky bit is if you're passing a Handler out of the non-UI thread. You either need to do it before the thread starts, or use appropriate thread synchronization operations to avoid data races.
You don't need to have your classes in the same file (and you really shouldn't unless one is nested inside the other). If they're in the same package then the default (package) scope will let them see each other. The first example from Grafika uses nested / private classes, the second example is more spread out.
Of course, if all you're trying to do is submit UI events from a non-UI thread, you can just use Activity.runOnUiThread().

Android acessing MainActivity from AsyncTask

My application crashes after click the button, but the code executes properly.
public void makeLead(View v) throws Exception {
try {
RegisterTimer rt = new RegisterTimer();
rt.ma = this;
rt.execute(null);
} catch (Exception e) {
e.printStackTrace();
}
}
public void log(String msg)
{
final TextView tv = (TextView)findViewById(R.id.editText);
tv.append(msg);
}
private class RegisterTimer extends AsyncTask {
public MainActivity ma;
#Override
protected Object doInBackground(Object[] objects) {
ma.log("ausd");
return null;
}
}
makeLead is onClick event. Method ma.log generates an error but works properly (msg added to textEdit). When I delete ma.log, app doesn't crash. I have no logs in my AndroidStudio so I can't see error message. What's wrong ?
You can not touch the Views in a non UI Thread.
and you are appending text to TextView in a background Thread which is not allowed.
and I hope there is no problem with the initialization of MainActivity inside RegisterTimer as you are not creating the instance of Activity manually. You are in correct way with the initialization rt.ma = this. and why do you need AsyncTask just for changing the text of a TextView?
You cannot update ui from a doInbackground. Initializing ma is not required
Make AsyncTask an inner class of Activity and update ui in onPostExecute
or use interface as a callback to the activity
Edit:
To make it clear
Make asynctaks an inner class of activity. Declare textview as a instance variable. Return result in doInbackground
In Activity
TextView tv;
#Override
public void onCreate(Bundle savedInstancestate)
super.onCreate(savedInstancestate);
setContentView(R.layout.yourlayout);
tv = (TextView)findViewById(R.id.editText);
Then
#Override
protected String doInBackground(Void objects) {
// some background computation
return "ausd";
}
In onpostExecute
#Override
protected void onPostExecute(String result)
{
super.onPostExecute();
tv.append(result);
}
Also you need
private class RegisterTimer extends AsyncTask<Void,Void,String> { // args missing
As described by #Raghunandan you have not initialized ma.
next is you cannot access view in background thread.
if your thread class is inside of MainActivity class then you can use
runOnUiThread(new Runnable() {
#Override
public void run() {
ma.log("ausd");
}
});
inside doInBackground method to update view.
Your method log is public, you don't need to make an object of the MainActivity class to access it, instead you can call it directly. Also you need to add some template after your ASYNC task, if you want to pass some input to your background process, you are using ASYNC task in a wrong way.

Show ProgressDialog during a network call until it's FINISHED

I am very frustrated as I've been trying to implement a super simple loading wheel while waiting on a network call. I have searched and read dozens of SO questions and I just feel like I must be missing something, unless nobody really does what I'm trying to do. I have tried going down the AsyncTask route, but that's not what I want.
Let me also say that right now my app works perfectly, it's just that the transition from screen to screen appears to hang as it waits on the network. I just want a loading wheel so that in the 1-2 seconds the user knows the app is working and didn't freeze.
Here's what my current network call looks like:
private static String sendDataToServer(String arg1, String arg2)
{
Thread dbThread = new Thread()
{
public void run()
{
// do the call that takes a long time
}
};
dbThread.start();
try {
// I do this so that my program doesn't continue until
// the network call is done and I have received the information
// I need to render my next screen
dbThread.join();
}
catch (InterruptedException e) {
e.printStackTrace();
}
}
Now, why can't I just add the ProgressDialog like this? If I do this, the progressDialog never appears.
private static String sendDataToServer(String arg1, String arg2)
{
final ProgressDialog progress = new ProgressDialog(BaseActivity.getInstance());
progress.setIndeterminate(true);
progress.setMessage("Loading...");
progress.show();
Thread dbThread = new Thread()
{
public void run()
{
// do the call that takes a long time
}
};
dbThread.start();
try {
dbThread.join();
progress.dismiss();
}
catch (InterruptedException e) {
e.printStackTrace();
}
}
I think I'm stuck because the network call needs to be on a separate thread from the UI thread, yet I don't want to continue in my application because I need the results of that call to continue. But if I do thread.join() I hold up everything. I thought I needed AsyncTask but that went downhill quickly. Here's my question on that if you're curious.
Android's AsyncTask: multiple params, returning values, waiting
How the heck to I just show a loading dialog while this call happens without proceeding through the rest of my application?
EDIT
Here's my AsyncTask attempt.
private class PostToFile extends AsyncTask<PostToFile, Void, Void>{
private String functionName;
private ArrayList<NameValuePair> postKeyValuePairs;
private String result = "";
public PostToFile(String function, ArrayList<NameValuePair> keyValuePairs){
functionName= function;
postKeyValuePairs = keyValuePairs;
}
#Override
protected void onPreExecute() {
progressDialog = ProgressDialog.show(BaseActivity.getInstance(), "Loading", "Please wait...", true, false);
}
#Override
protected Void doInBackground(PostToFile... params) {
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair(FUNCTION_KEYWORD, functionName));
for (int i = 0; i < postKeyValuePairs.size(); i++) {
nameValuePairs.add(postKeyValuePairs.get(i));
}
try{
// ***do the POST magic.***
result = response.toString();
}
catch (Exception e){
// clean up my mess
}
return null;
}
private String getResult(){
return result; // can I use this somehow???
}
#Override
protected void onPostExecute(Void result) {
progressDialog.dismiss();
}
}
And when I use it:
new PostToPHP(FUNCTION_NAME, postPairings){
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
try
{
if (result != null && !result.startsWith("null"))
{
JSONArray jArray = new JSONArray(result);
parseData(jArray);
}
}
catch (JSONException e)
{
Log.e(Constants.LOG_TAG, e.toString());
}
};
}.execute()
The problem is, I have a couple of these calls back to back, and they're each dependent on each other. So the first one starts, and the second one starts immediately after the first one starts, but before the first one is finished. So I get erroneous behavior. How can I start the second call only after the first is completely done?
Maybe this will work, I haven't tested, but you can try:
public class MyTask extends AsyncTask<String, Void, String> {
private int flag;
public MyTask(int flag) {
this.flag = flag;
}
#Override
protected String doInBackground(String... params) {
switch (flag) {
case 1:
return doNetworking1();
break;
case 2:
return doNetworking2();
break;
case 3:
return doNetworking3();
break;
default:
return doNetworking1();
}
}
#Override
protected void onPreExecute() {
//show progress dialog
}
#Override
protected void onPostExecute(String s) {
//hide progress dialog
switch (flag) {
case 1: //do something with result
new MyTask(2).execute();
break;
case 2: //do other stuff
new MyTask(3).execute();
break;
case 3: //do event more stuff
break;
default:
//do something
}
}
}
and usage:
new MyTask(1).execute();
In cases of network connections I would use IntentService instead of AsyncTask.
For example create IntentServices for network connection:
public class NetworkCallIntentService extends IntentService {
public static final String BROADCAST_ACTION = "com.yourpackage:NETWORK_CALL_BROADCAST";
public static final String RESULT = "com.yourpackage:NETWORK_CALL_RESULT";
public NetworkCallIntentService() {
super(NetworkCallIntentService.class.getSimpleName());
}
#Override
protected void onHandleIntent(Intent intent) {
// get data from intent if needed
// do the call that takes long time
// send broadcast when done
Intent intent = new Intent(BROADCAST_ACTION);
intent.putExtra(RESULT, "some_result");//and more results
LocalBroadcastManager.getInstance(this).sendBroadcast(intent);
}
}
Next, start that service from activity, show progress dialog and move code responsible for showing next screen to BroadcastReceiver#onReceive() method:
public class SomeActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//start service
Intent serviceIntent = new Intent(this, NetworkCallIntentService.class);
//put extras into intent if needed
//serviceIntent.putExtra("some_key", "some_string_value");
startService(serviceIntent);
//here just show progress bar/progress dialog
}
#Override
protected void onResume() {
super.onResume();
LocalBroadcastManager.getInstance(getApplicationContext()).registerReceiver(mNetworkCallReceiver,
new IntentFilter(NetworkCallIntentService.BROADCAST_ACTION));
}
#Override
protected void onPause() {
super.onPause();
LocalBroadcastManager.getInstance(getApplicationContext()).unregisterReceiver(mNetworkCallReceiver);
}
private BroadcastReceiver mNetworkCallReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
//hide progress bar/progress dialog
//here get results from intent extras
String result = intent.getStringExtra(NetworkCallIntentService.RESULT);
//process results and continue program(go to next screen, show error message etc.)
}
}
}
Declare service in manifest file:
<service
android:name="com.yourpackage.DownloadSvtValuesIntentService"
android:exported="false" >
</service>

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