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myHandler.obtainMessage() is not allowed in Service class in android

I am trying to create a service class with a inner class which is a Handler class , unfortunately I am not able to access handler.obtainMessage() in this class .. Can any one give suggestions on this ?
Source code for the Service class:
public class MyService extends Service {
private MyHandler myHandler;
private final class MyHandler extends Handler {
public MyHandler(Looper looper) {
super(looper);
}
public void handleMessage(Message msg) {
try {
Thread.sleep(5000);
// use the unique startId so you don't stop the
// service while processing other requests
stopSelfResult(msg.arg1);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
#Override
public void close() {
}
#Override
public void flush() {
}
#Override
public void publish(LogRecord record) {
}
}
#Override
public void onCreate() {
Toast.makeText(this, "Service Created", Toast.LENGTH_SHORT).show();
// Create a new HandlerThread with a specified priority
HandlerThread thread = new HandlerThread("MyHandlerThread",Thread.NORM_PRIORITY);
// Start the handler thread so that our Handler queue will start
// processing messages
thread.start();
// Run the handler using the new HandlerThread
myHandler = new MyHandler(thread.getLooper());
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Message msg = myHandler.obtainMessage();
msg.arg1 = startId;
myHandler.sendMessage(msg);
return START_STICKY;
}
#Override
public IBinder onBind(Intent arg0) {
return null;
}
#Override
public void onDestroy() {
Toast.makeText(this, "Service Done", Toast.LENGTH_SHORT).show();
}
}

You've got the wrong Handler class imported. It should be android.os.Handler, not java.util.logging.Handler.

continue service working when the application closes

I have a simple Service
public class UpdateService extends Service {
private int seconds;
final static String MY_ACTION = "MY_ACTION";
#Override
public void onCreate() {
super.onCreate();
}
#Override
public void onStart(Intent intent, int startId) {
timer.start();
}
#Override
public IBinder onBind(Intent intent) {
return null;
}
final CountDownTimer timer = new CountDownTimer(86400000, 1000) {
public void onTick(long millisUntilFinished) {
Util.saveInfo(getApplicationContext(), Util.SECONDS, seconds++);
Intent intent = new Intent();
intent.setAction(MY_ACTION);
sendBroadcast(intent);
}
public void onFinish() { }
};
}
When I close an application service stops working. But showing that the service is running.
What am I doing wrong?
Update
I changed CountDownTimer to Thread, but the problem remained
Thread t1 = new Thread(new Runnable() {
#Override
public void run() {
while (true) {
Util.saveInfo(getApplicationContext(), Util.SECONDS, seconds++);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
});
OnStart()
if(!t1.isAlive())
t1.start();

Because CountDown Timer is working only foreground means app is running and not minimized or closed. You have to place a Thread in Service that executing at particular time of you want.
try this :
public class LocalService extends Service
{
private static Timer timer = new Timer();
private Context ctx;
public IBinder onBind(Intent arg0)
{
return null;
}
public void onCreate()
{
super.onCreate();
ctx = this;
startService();
}
private void startService()
{
timer.scheduleAtFixedRate(new mainTask(), 0, 5000);
}
private class mainTask extends TimerTask
{
public void run()
{
toastHandler.sendEmptyMessage(0);
}
}
public void onDestroy()
{
super.onDestroy();
Toast.makeText(this, "Service Stopped ...", Toast.LENGTH_SHORT).show();
}
private final Handler toastHandler = new Handler()
{
#Override
public void handleMessage(Message msg)
{
System.out.println("test");
}
};
}

android - how can I stop the thread inside the service?

I have a checked button in my MainActivity. If that button is checked it should start the service but if a user unchecked the button I want to stop the service.
So in uncheck condition I have written this stopService(intentname); but the problem is the service is not stopping. Here is my code snippet:
Service Class
public class SimpleService extends Service
{
String selectedAudioPath = "";
private MyThread myythread;
public Intent intent;
public boolean isRunning = false;
long interval=30000;
#Override
public IBinder onBind(Intent arg0)
{
return null;
}
#Override
public void onCreate()
{
super.onCreate();
myythread = new MyThread(interval);
}
#Override
public synchronized void onDestroy()
{
super.onDestroy();
if(!isRunning)
{
myythread.interrupt();
myythread.stop();
isRunning = false;
}
}
#Override
public synchronized void onStart(Intent intent, int startId)
{
super.onStart(intent, startId);
if(!isRunning)
{
//this.intent = intent;
//System.out.println("the intent is" + intent);
myythread.start();
isRunning = true;
}
}
class MyThread extends Thread
{
long interval;
public MyThread(long interval)
{
this.interval=interval;
}
#Override
public void run()
{
while(isRunning)
{
System.out.println("Service running");
try
{
String myString = intent.getStringExtra("name");
if(myString == null)
Log.d("Service","null");
else
{
Log.d("Service","not null");
if(myString.equalsIgnoreCase("image"))
{
uploadImages();
Thread.sleep(interval);
}
else if(myString.equalsIgnoreCase("audio"))
{
uploadAudio();
Thread.sleep(interval);
}
}
}
catch (InterruptedException e)
{
isRunning = false;
e.printStackTrace();
}
}
}

You can't stop a thread that has a running unstoppable loop like this
while(true)
{
}
To stop that thread, declare a boolean variable and use it in while-loop condition.
public class MyService extends Service {
...
private Thread mythread;
private boolean running;
#Override
public void onDestroy()
{
running = false;
super.onDestroy();
}
#Override
public void onStart(Intent intent, int startid) {
running = true;
mythread = new Thread() {
#Override
public void run() {
while(running) {
MY CODE TO RUN;
}
}
};
};
mythread.start();
}
Source: Stopping a thread inside a service

Don't use Threads. Use AsyncTask instead.
public class MyService extends Service {
private AsyncTask<Void,Void,Void> myTask;
#Override
public void onDestroy(){
super.onDestroy();
myTask.cancel(true);
}
#Override
public void onStart(Intent intent, int startid) {
myTask = new AsyncTask<Void,Void,Void>(){
#Override
public void doInBackground(Void aVoid[]){
doYourWorkHere();
}
}
myTask.execute();
}
}

IntentService won't show Toast

This IntentService I created will show Toasts in onStartCommand() and in onDestroy(), but not in onHandleIntent(). Am I missing something about the limitations of an IntentService?
public class MyService extends IntentService {
private static final String TAG = "MyService";
public MyService(){
super("MyService");
}
#Override
protected void onHandleIntent(Intent intent) {
cycle();
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Toast.makeText(this, "service starting", Toast.LENGTH_SHORT).show(); //This happens!
return super.onStartCommand(intent,flags,startId);
}
#Override
public void onCreate() {
super.onCreate();
}
#Override
public void onDestroy() {
Toast.makeText(this, "service stopping", Toast.LENGTH_SHORT).show(); //This happens!
super.onDestroy();
}
private void cycle(){
Toast.makeText(this, "cycle done", Toast.LENGTH_SHORT).show(); //This DOESN'T happen!
Log.d(TAG,"cycle completed"); //This happens!
}
}

The accepted answer is not correct.
Here is how you can show toast from onHandleIntent():
Create a DisplayToast class:
public class DisplayToast implements Runnable {
private final Context mContext;
String mText;
public DisplayToast(Context mContext, String text){
this.mContext = mContext;
mText = text;
}
public void run(){
Toast.makeText(mContext, mText, Toast.LENGTH_SHORT).show();
}
}
Instantiate a Handler in your service's constructor and call the post method with a DisplayToast object inside.
public class MyService extends IntentService {
Handler mHandler;
public MyService(){
super("MyService");
mHandler = new Handler();
}
#Override
protected void onHandleIntent(Intent intent) {
mHandler.post(new DisplayToast(this, "Hello World!"));
}
}

You should start the Toast on the main thread:
new Handler(Looper.getMainLooper()).post(new Runnable() {
#Override
public void run() {
Toast.makeText(getApplicationContext(), message, Toast.LENGTH_LONG).show();
}
});
This is because otherwise the thread of the IntentService quits before the toast can be send out, causing a IllegalStateException:
java.lang.IllegalStateException: Handler (android.os.Handler) {12345678} sending message to a Handler on a dead thread

onHandleIntent() is called from a background thread (that is what IntentService is all about), so you shouldn't do UI from there.

Another option is RxJava, e.g.:
private void showToast(final String text) {
Observable.just(text)
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new Action1<String>() {
#Override
public void call(String s) {
Toast.makeText(getApplicationContext(), s, Toast.LENGTH_LONG).show();
}
});
}
Caveat: I'm new to Android.

Android Timer within a service

I am having problems running a timer in a service I have created. The task that the timer calls simply isn't called. I know that the service starts as I have put toasts within it and they are called, but not when they are within the timer. Help appreciated.
service class:
public class LocalService extends Service
{
private static Timer timer = new Timer();
private Context ctx;
public IBinder onBind(Intent arg0)
{
return null;
}
public void onCreate()
{
super.onCreate();
ctx = this;
startService();
}
private void startService()
{
timer.scheduleAtFixedRate(new mainTask(), 0, 5000);
}
private class mainTask extends TimerTask
{
public void run()
{
Toast.makeText(ctx, "test", Toast.LENGTH_SHORT).show();
}
}
public void onDestroy()
{
super.onDestroy();
Toast.makeText(this, "Service Stopped ...", Toast.LENGTH_SHORT).show();
}
}
Main class:
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
startService(new Intent(RingerSchedule.this, LocalService.class));
}

Android does not allow UI events like Toasts from outside the main thread. The run is getting called, but the Toast is being ignored.
To create the Toast on the UI thread, you can use a Handler and an empty Message like so:
public class LocalService extends Service
{
private static Timer timer = new Timer();
private Context ctx;
public IBinder onBind(Intent arg0)
{
return null;
}
public void onCreate()
{
super.onCreate();
ctx = this;
startService();
}
private void startService()
{
timer.scheduleAtFixedRate(new mainTask(), 0, 5000);
}
private class mainTask extends TimerTask
{
public void run()
{
toastHandler.sendEmptyMessage(0);
}
}
public void onDestroy()
{
super.onDestroy();
Toast.makeText(this, "Service Stopped ...", Toast.LENGTH_SHORT).show();
}
private final Handler toastHandler = new Handler()
{
#Override
public void handleMessage(Message msg)
{
Toast.makeText(getApplicationContext(), "test", Toast.LENGTH_SHORT).show();
}
};
}

Thanks, I also needed to cancel the timer ..
public void onDestroy() {
timer.cancel();
Toast.makeText(this, "ServiceTalkGeology stopped.",
Toast.LENGTH_SHORT).show();
super.onDestroy();
}