Develop Reference

How to run a Service always in background (Non-Stop) - Android

I have created a Service in my android application which starts running on BOOT_COMPLETE. I want to run my Service non-stop (run always), and for that I have used while(true) inside onStartCommand() method. So is this fine to use while(true) or there is any other better way to run a service always in background?
This is code of my Service:
package com.example.abc.project1;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import org.json.*;
import java.io.*;
import java.net.*;
import java.util.*;
public class HelloService extends Service {
private static final String TAG = "HelloService";
private boolean isRunning = false;
#Override
public IBinder onBind(Intent arg0) {
return null;
}
#Override
public void onCreate() {
super.onCreate();
isRunning = true;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
new Thread(new Runnable() {
#Override
public void run() {
while(true) {
/*non-stop work to be done in background always*/
}
}
}).start();
return Service.START_STICKY;
}
#Override
public void onDestroy() {
isRunning = false;
}
}

I have not tried this myself but if you change receiver to service it should work.

IntentService Thread.sleep() limit?

i was wondering if the IntentService has thread blocking limit like calling Thread.sleep(); and if so what's the maximum time limit for it?
so i wrote the following code snippet:
package net.yassin.aaaservice;
import android.app.IntentService;
import android.content.Intent;
import android.os.Handler;
import android.os.SystemClock;
import android.widget.Toast;
public class MyService extends IntentService {
private Thread t;
private static int i = 0;
private static final int SLEEP_DURATION = 2000;
private Handler handler;
public MyService() {
super("MyService");
}
#Override
public void onStart(Intent intent, int startId) {
super.onStart(intent, startId);
this.handler = new Handler();
}
#Override
protected void onHandleIntent(Intent arg0) {
this.t = new Thread(new Runnable() {
#Override
public void run() {
while (true) {
MyService.this.handler.post(new Runnable() {
#Override
public void run() {
Toast.makeText(MyService.this,
"This is toast #" + (++i),
Toast.LENGTH_SHORT).show();
}
});
try {
Thread.sleep(SLEEP_DURATION);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
});
this.t.start();
}
}
and i found that whenever i change the time SLEEP_DURATION constant to over than 2000 Milis the service will stop showing Toasts if i removed the app form the recent menu?
am i right or there is another time limit or behavior ?
thnx :)

how can show toast from service every 10 seconds

I have an android application and I want to show a notification or toast every 10 seconds for example from Service when application is closed or finished

I have provided below a sample activity, a service class and a Timer class. use similar implementation in your application.
Activity Class
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.widget.Button;
public class Sample extends Activity {
Button button1,button2;
private Handler mHandler = new Handler();
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Call the start and stop method when needed.
}
public void Start(View v)
{
startService(new Intent(MainActivity.this , Sample_service.class));
}
public void Stop(View v)
{
stopService(new Intent(MainActivity.this , Sample_service.class));
}
}
Service Class
package com.example.connect;
import java.util.Timer;
import java.util.TimerTask;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.widget.Toast;
public class Sample_service extends Service{
Timer timer = new Timer();
TimerTask updateProfile = new CustomTimerTask(Sample_service.this);
public void onCreate() {
super.onCreate();
Toast.makeText(this, "Service Started", Toast.LENGTH_SHORT).show();
timer.scheduleAtFixedRate(updateProfile, 0, 10000);
}
#Override
public void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
Toast.makeText(this, "Service Stopped", Toast.LENGTH_SHORT).show();
timer.cancel();
}
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
}
Timer class
package com.example.connect;
import java.util.TimerTask;
import android.content.Context;
import android.os.Handler;
import android.widget.Toast;
public class CustomTimerTask extends TimerTask {
private Context context;
private Handler mHandler = new Handler();
public CustomTimerTask(Context con) {
this.context = con;
}
#Override
public void run() {
new Thread(new Runnable() {
public void run() {
mHandler.post(new Runnable() {
public void run() {
Toast.makeText(context, "DISPLAY YOUR MESSAGE", Toast.LENGTH_SHORT).show();
}
});
}
}).start();
}
}

I have given here three files,MainActivity,Manifest and MyService file implement it in your application and it will display toast service at every 10 seconds.
MainActivity.java
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);//load the layout file
startService(new Intent(this,MyService.class));//use to start the services
}
}
MyService.java
public class MyService extends Service {
public static final long INTERVAL=10000;//variable to execute services every 10 second
private Handler mHandler=new Handler(); // run on another Thread to avoid crash
private Timer mTimer=null; // timer handling
#Nullable
#Override
public IBinder onBind(Intent intent) {
throw new UnsupportedOperationException("unsupported Operation");
}
#Override
public void onCreate() {
// cancel if service is already existed
if(mTimer!=null)
mTimer.cancel();
else
mTimer=new Timer(); // recreate new timer
mTimer.scheduleAtFixedRate(new TimeDisplayTimerTask(),0,INTERVAL);// schedule task
}
#Override
public void onDestroy() {
Toast.makeText(this, "In Destroy", Toast.LENGTH_SHORT).show();//display toast when method called
mTimer.cancel();//cancel the timer
}
//inner class of TimeDisplayTimerTask
private class TimeDisplayTimerTask extends TimerTask {
#Override
public void run() {
// run on another thread
mHandler.post(new Runnable() {
#Override
public void run() {
// display toast at every 10 second
Toast.makeText(getApplicationContext(), "Notify", Toast.LENGTH_SHORT).show();
}
});
}
}
}
AndroidManifest.xml
<service android:name=".MyService"
android:enabled="true"/>

Technically, When task is executed which you wrote in onCreate() method, It automatically close. For this you can use timer/scheduler.
Example :
Timer timer;
TimerTask timerTask;
timer.schedule(timerTask, 5000, 10000);
timerTask = new TimerTask() {
public void run() {
//use a handler to run a toast that shows the current timestamp
handler.post(new Runnable() {
public void run() {
Toast toast = Toast.makeText(getApplicationContext(), strDate, duration);
toast.show();
}
});
}
};

Don't forget to add your service in the manifest file inside the application Tag :
<service android:name=".ServiceGPS"
android:permission="[Add permission here if exists]"
android:label="[service name]" android:exported="true"
android:enabled="true">
</service>

Calendar value not updating in android service

In this android service I wanna display a toast of value of second at current time. but this again and again show the same value. timer is scheduled to update at interval of 1 second but the value don't refresh and toast shows the previous value again. I don't what the issue.
package net.learn2develop.Services;
import java.util.Calendar;
import java.util.Timer;
import java.util.TimerTask;
import android.app.Service;
import android.content.Intent;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.widget.Toast;
public class MyService extends Service{
Handler handler = new Handler();
Calendar c = Calendar.getInstance();
Timer t = new Timer();
int second = c.get(Calendar.SECOND);
int temp = 6;
#Override
public void onCreate() {
super.onCreate();
Toast.makeText(this, "Service Created", Toast.LENGTH_SHORT).show();
}
#Override
public IBinder onBind(Intent arg0) {
return null;
}
public int onStartCommand(Intent intent, int flags, int startId){
Toast.makeText(this,"service started",Toast.LENGTH_SHORT).show();
TimerTask task = new TimerTask() {
#Override
public void run() {
second = timeSecond();
handler.post(new Runnable() {
#Override
public void run() {
// Toast.makeText(getBaseContext(),String.valueOf(second), Toast.LENGTH_SHORT).show();
}
});
}
};
t.scheduleAtFixedRate(task, 0, 4* 1000);
return START_STICKY;
}
public void onDestroy(){
super.onDestroy();
t.cancel();
Toast.makeText(this, "Service Stopped", Toast.LENGTH_SHORT).show();
}
public int timeSecond() {
handler.post(new Runnable() {
#Override
public void run() {
Toast.makeText(getBaseContext(),String.valueOf(c.get(Calendar.SECOND)), Toast.LENGTH_SHORT).show();
}
});
return c.get(Calendar.SECOND);
}
}

This statement:
Calendar c = Calendar.getInstance();
returns a calendar whose time fields have been initialized with the current date and time. Those values do not then change as time passes. So when you use:
String.valueOf(c.get(Calendar.SECOND))
you are getting the same values every time. You need a new instance of calendar in each iteration of your timer.

How can we call an activity through service in android?

I want to know if it is possible to call an activity through background service in android like :
import android.app.Service;
import android.content.Intent;
import android.content.SharedPreferences;
import android.media.MediaPlayer;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
public class background extends Service{
private int timer1;
#Override
public void onCreate() {
// TODO Auto-generated method stub
super.onCreate();
SharedPreferences preferences = getSharedPreferences("SaveTime", MODE_PRIVATE);
timer1 = preferences.getInt("time", 0);
startservice();
}
#Override
public IBinder onBind(Intent arg0) {
// TODO Auto-generated method stub
return null;
}
private void startservice() {
Handler handler = new Handler();
handler.postDelayed(new Runnable(){
public void run() {
mediaPlayerPlay.sendEmptyMessage(0);
}
}, timer1*60*1000);
}
private Handler mediaPlayerPlay = new Handler(){
#Override
public void handleMessage(Message msg) {
try
{
getApplication();
MediaPlayer mp = new MediaPlayer();
mp = MediaPlayer.create(background.this, R.raw.alarm);
mp.start();
}
catch(Exception e)
{
e.printStackTrace();
}
super.handleMessage(msg);
}
};
/*
* (non-Javadoc)
*
* #see android.app.Service#onDestroy()
*/
#Override
public void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
}
}
i want to call my activity......

You can call an Activity while onStart() of your service.....
Snippet might be as follows:
#Override
public void onStart(Intent intent, int startId) {
...
Log.i("Service", "onStart() is called");
Intent callIntent = new Intent(Intent.ACTION_CALL);
callIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
callIntent.setClass(<Set your package name and class name here>);
startActivity(callIntent);
...
}

I believe launching user-interactive Activity from a non-interactive Service goes against the design of Android, in that it would pull out control from under the user.
Notifications are the mechanism intended to get user's attention from a background app, and give them an opportunity to launch the interactive Activity.