Develop Reference

Cannot bind to service in android

I am working on a larger project but have become stuck on a very simple element that is binding to an android service. My issue is that I cannot seem to bind to the service. No errors are being thrown at all when calling bindService() and I have used the internal debugger and manual tracing of print statements and I am still failing to understand what is causing this error. Any help appreciated! (This is especially irritating as it is largely C+P from the android development website yet still won't work!)
Main Activity:
package com.example.servicetest;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
public class MainActivity extends Activity {
LocalService mService;
boolean mBound = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// START Activity
Intent intent = new Intent(this, BindingActivity.class);
startActivity(intent);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
Binding Activity:
package com.example.servicetest;
import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.view.View;
import android.widget.Toast;
import com.example.servicetest.LocalService.LocalBinder;
public class BindingActivity extends Activity {
LocalService mService;
boolean mBound = false;
/** Defines callbacks for service binding, passed to bindService() */
private ServiceConnection mConnection = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName className,
IBinder service) {
// We've bound to LocalService, cast the IBinder and get LocalService instance
LocalBinder binder = (LocalBinder) service;
mService = binder.getService();
mBound = true;
System.out.println("End onServiceConnected");
}
#Override
public void onServiceDisconnected(ComponentName arg0) {
mBound = false;
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_bind);
}
#Override
protected void onStart() {
super.onStart();
// Bind to LocalService
System.out.println("onStart called");
Intent intent = new Intent(this, LocalService.class);
bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
this.startService(intent);
}
#Override
protected void onStop() {
super.onStop();
// Unbind from the service
if (mBound) {
unbindService(mConnection);
mBound = false;
}
}
/** Called when a button is clicked (the button in the layout file attaches to
* this method with the android:onClick attribute) */
public void onButtonClick(View v) {
if (mBound) {
// Call a method from the LocalService.
// However, if this call were something that might hang, then this request should
// occur in a separate thread to avoid slowing down the activity performance.
System.out.println("Button click");
int num = mService.getRandomNumber();
Toast.makeText(this, "number: " + num, Toast.LENGTH_SHORT).show();
System.out.println("" + num);
} else {
System.out.println("Not bound");
}
}
}
LocalService:
package com.example.servicetest;
import java.util.Random;
import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
public class LocalService extends Service {
// Binder given to clients
private final IBinder mBinder = new LocalBinder();
// Random number generator
private final Random mGenerator = new Random();
/**
* Class used for the client Binder. Because we know this service always
* runs in the same process as its clients, we don't need to deal with IPC.
*/
public class LocalBinder extends Binder {
LocalService getService() {
// Return this instance of LocalService so clients can call public methods
return LocalService.this;
}
}
#Override
public IBinder onBind(Intent intent) {
System.out.println("onBind called");
return mBinder;
}
/** method for clients */
public int getRandomNumber() {
return mGenerator.nextInt(100);
}
}
And finally the manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.servicetest"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="18" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.servicetest.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.example.servicetest.BindingActivity"
android:label="#string/app_name" >
</activity>
</application>
</manifest>

I think you need to add your service in Mainfest.xml
<service android:name="LocalService" android:enabled="true"></service>
try it and feed me back

android activity/service works only if phone connected to pc

I know this sounds weird, but I created a simple timer with an activity and a service (started and bound).
In the activity I also implemented onStart and onStop just logging a message (Log.d(TAG,"activity started/stopped").
The fact is that if the phone is connected to the pc everything seems to work. I can start the timer, pause it, modify and restart it. Open other apps and it keeps working on the background. I can recall it and I see the actual countdown going down. If it finish I can recall the activity from a notification and stop the ringing. etc etc
If the phone it's detached from the pc, that it works like there is no service at all. So the activity runs and if I press the home button it goes on the background and keeps working for a couple of minutes than it stops.
I can see the process in the running applications and if I recall the activity it restart from the point where it paused. That is, I set 10 minutes, I click start and then the home button. After 2-3 minutes it stops working and if I recall the activity it continues counting down from 8-7 minutes...
Any idea?
The activity:
package com.sleone.cookingtimer;
import com.sleone.cookingtimer.TimerService.LocalBinder;
import android.os.Bundle;
import android.os.IBinder;
import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import kankan.wheel.widget.WheelView;
import kankan.wheel.widget.adapters.NumericWheelAdapter;
import android.util.Log;
public class TimerMainActivity extends Activity {
// private CookingTimer timer;
// suppressWarnings because is initialized binding to the service
private TimerService timerService;
private Intent timerServiceIntent;
private final String TAG = "TimerMainActivity";
private WheelView hoursWheel ;
private WheelView minutesWheel;
private WheelView secondsWheel;
/*
* Initialize the activity
*/
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_timer_main);
timerServiceIntent = new Intent(this, TimerService.class);
startTimerService();
// init the gui
hoursWheel = (WheelView) findViewById(R.id.hoursWheelView);
minutesWheel = (WheelView) findViewById(R.id.minutesWheelView);
secondsWheel = (WheelView) findViewById(R.id.secondsWheelView);
hoursWheel.setViewAdapter(new NumericWheelAdapter(this, 0, 6));
minutesWheel.setViewAdapter(new NumericWheelAdapter(this, 0, 59));
secondsWheel.setViewAdapter(new NumericWheelAdapter(this, 0, 59));
}
#Override
protected void onStop(){
super.onStop();
Log.d(TAG, "TimerMainActivity stopped");
}
#Override
protected void onStart(){
super.onStart();
Log.d(TAG, "TimerMainActivity started");
}
private void startTimerService() {
// connect to the service
// leave the service in background
Log.d(TAG, "Starting the TimerService");
startService(timerServiceIntent);
// interact with the service
Log.d(TAG, "Binding to the TimerService");
bindService(timerServiceIntent, mConnection, Context.BIND_AUTO_CREATE);
}
private void stopTimerService() {
unbindService(mConnection);
stopService(timerServiceIntent);
}
/*
* Disconnect from the service
*/
#Override
protected void onDestroy() {
Log.d(TAG, "Stopping TimerService");
super.onStop();
stopTimerService();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.timer_main, menu);
return true;
}
public void controlTimer(View view) {
Button controlButton = (Button) findViewById(R.id.controlTimerButton);
if (controlButton.getText().equals(
getResources().getText(R.string.startTimer))) {
if ((hoursWheel.getCurrentItem() == 0)
&& (minutesWheel.getCurrentItem() == 0)
&& (secondsWheel.getCurrentItem() == 0)) {
return;
}
controlButton.setText(R.string.stopTimer);
timerService.startTimer();
} else {
controlButton.setText(R.string.startTimer);
timerService.stopTimer();
}
}
/* Defines callbacks for service binding, passed to bindService() */
private ServiceConnection mConnection = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName className, IBinder service) {
// We've bound to LocalService, cast the IBinder and get
// LocalService instance
LocalBinder binder = (LocalBinder) service;
timerService = binder.getService();
binder.createCookingTimer(TimerMainActivity.this);
Log.d(TAG, "onServiceConnected() finished");
}
#Override
public void onServiceDisconnected(ComponentName arg0) {
Log.e(TAG, "TimerService unexpectedly disconnected!!");
}
};
}
The service:
package com.sleone.cookingtimer;
import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
public class TimerService extends Service{
// Binder given to clients
private final IBinder mBinder = new LocalBinder();
private CookingTimer timer;
//private int timerServiceId;
public class LocalBinder extends Binder {
public TimerService getService() {
// Return this instance of LocalService so clients can call public methods
return TimerService.this;
}
// when the client connects to the service instantiate the CookingImer
public void createCookingTimer(TimerMainActivity timerMainActivity){
timer = new CookingTimer(timerMainActivity);
}
}
public void startTimer(){
timer.startTimer();
}
public void stopTimer(){
timer.stopTimer();
}
#Override
public IBinder onBind(Intent arg0) {
// TODO Auto-generated method stub
return mBinder;
}
}
I don't think you need the timer itself. It;s just a CountDownTimer which onTick it updates the hours/minutes/seconds Wheel and onFinish plays a sound and create a notification.

You might have some sort of race condition, that when connected to the PC, execution is a bit slower, but when not connected the timing is a bit different and the order of execution changes. It's hard to tell without the code.

Ok, I guess I figured it out.
Basically I did not understand exactly that a service could also be paused when the cpu goes to sleep.
So, my guess is that while on the emulator or with the cable connected the cpu never goes to sleep because there is no battery consumption.
To wake up the application even from the cpu sleep I used an AlarmManger with the AlarmManager.RTC_WAKEUP flag.

Can't bind an Activity to Service

I'm having trouble getting the onServiceConnected() method to run, which means that it's not binding my activity to the service.
It's probably something simple that I've missed out - but I've tried quite a few times - starting from scratch.
Here we go...
My Service Class
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
public class QuickService extends Service {
private final IBinder mBinder = new QuickBinder(this);
#Override
public IBinder onBind(Intent intent) {
return mBinder;
}
}
My Binder Class
import android.os.Binder;
public class QuickBinder extends Binder {
private final QuickService service;
public QuickBinder(QuickService service){
this.service = service;
}
public QuickService getService(){
return service;
}
}
And... The Activity trying to bind to the service.
import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
public class QuickActivity extends Activity {
QuickService mService;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_connecting);
}
#Override
protected void onStart() {
super.onStart();
Intent intent = new Intent(this, QuickService.class);
bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
}
#Override
protected void onStop() {
super.onStop();
// Unbind from the service
unbindService(mConnection);
}
/** Defines callbacks for service binding, passed to bindService() */
private ServiceConnection mConnection = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName className,
IBinder service) {
Logger.d("Connected!!! :D");
// We've bound to LocalService, cast the IBinder and get LocalService instance
QuickBinder binder = (QuickBinder) service;
mService = binder.getService();
}
#Override
public void onServiceDisconnected(ComponentName arg0) {
}
};
}
Also, the Service defined in the manifest file - in case you thought that was the problem.
<service android:name=".QuickService"></service>
So, What am I doing wrong here? Why isn't the onServiceConnected() method being called?

Update it with following
<service android:name=".QuickService">
<intent-filter>
<action android:name=".QuickService .BIND" />
<category android:name="android.intent.category.DEFAULT"/>
</intent-filter>
</service>

Instead of writing:
Intent intent = new Intent(this, QuickService.class);
bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
You can write:
startService(new Intent(QuickActivity.this, QuickService.class));
where you want to start service.
Hope this will help you.

Creating an android service

I'm trying to create a service which will start by the user request in the application.
After the user will choose an update interval, the service will run in the operation system background, and will send a non-relevant message.
I've tried to write the service according to the example for Service class API.
For some reason, I figured in debug (when running doBindService() method) that mUpdateBoundService is getting null.
My second question is whether I can use "Toast" inform message outside an application ? (As kind of a desktop notification).
Can anyone help ? Here is my short code:
UpdateService.java
package android.update;
import java.util.Timer;
import java.util.TimerTask;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.widget.Toast;
public class UpdateService extends Service {
private NotificationManager mNM;
private final IBinder mBinder = new UpdateBinder();
private int updateInterval;
public class UpdateBinder extends Binder {
UpdateService getService() {
return UpdateService.this;
}
}
public void onCreate() {
mNM = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
Timer timer = new Timer();
timer.schedule(new UpdateTimeTask(), 100, updateInterval);
}
public int onStartCommand(Intent intent, int flags, int startId) {
return START_STICKY;
}
class UpdateTimeTask extends TimerTask {
public void run() {
showNotification();
}
}
public void showNotification() {
Toast.makeText(this, "Hi", 10);
}
#Override
public IBinder onBind(Intent intent) {
updateInterval = intent.getExtras().getInt(getString(R.string.keyUpdateInterval));
return mBinder;
}
}
UpdateActivity.java
package android.update;
import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;
public class UpdateActivity extends Activity {
private UpdateService mUpdateBoundService;
private boolean mIsBound = false;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
public void onClickStartUpdateService(View view) {
switch (view.getId()) {
case R.id.btnStartUpdateService:
doBindService();
//Toast.makeText(this,"Service Started",Toast.LENGTH_LONG).show();
mUpdateBoundService.showNotification();
break;
}
}
private ServiceConnection mConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className, IBinder service) {
mUpdateBoundService = ((UpdateService.UpdateBinder)service).getService();
}
public void onServiceDisconnected(ComponentName className) {
mUpdateBoundService = null;
}
};
private void doBindService() {
Intent updateActivityIntent = new Intent(UpdateActivity.this,
UpdateService.class);
EditText txtUpdateInterval = (EditText) findViewById(R.id.txtUpdateInterval);
int interval = Integer.parseInt(txtUpdateInterval.getText().toString());
updateActivityIntent.putExtra(getString(R.string.keyUpdateInterval), interval);
bindService(updateActivityIntent, mConnection, Context.BIND_AUTO_CREATE);
mIsBound = true;
}
void doUnbindService() {
if (mIsBound) {
unbindService(mConnection);
mIsBound = false;
}
}
#Override
protected void onDestroy() {
super.onDestroy();
doUnbindService();
}
}

Your toast is not showing because you are not telling it to. Try:
public void showNotification() {
Toast.makeText(this, "Hi", 10).show();
}
For your service issue, I think that you do not properly understand how services & activities work together. A service can run independently of a service, or you can have a service whose lifecycle matches that of a given activity. From your code, it is not clear which of these models you are following. Your implementation will cause the service to wake periodically, but only while your activity is running. If the user switches to another activity, your service will no longer be woken.
If you want a service to wake periodically independently of the activity, then you need to run your timer event in the service itself. Better still use an Alarm to wake your service: Register an Alarm with AlarmManager which will fire an Intent at a future point (or regular intervals, if you prefer), and extend your service from IntentService, override onHandleIntent() and add the necessary Intent Filter to your Service entry in the manifest.

Can't bind to service when following instructions in tutorial from Android Developers website

Although I followed the tutorial on the Android Developers website, I can't get my activity to bind to my service.
package com.dieselboris.motioncapture;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import com.dieselboris.motioncapture.LocalService.LocalBinder;
public class HelloMotionCaptureActivity extends Activity implements OnClickListener {
private TextView textBox;
LocalService mService;
boolean mBound = false;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
textBox = (TextView) findViewById(R.id.textView1);
}
#Override
protected void onStart() {
super.onStart();
// Bind to LocalService NEVER RETURNS TRUE!!!!
Intent intent = new Intent(this, LocalService.class);
boolean isBound = bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
String text = Boolean.toString(isBound);
textBox.setText(text);
}
#Override
protected void onStop() {
super.onStop();
// Unbind from the service
if (mBound) {
unbindService(mConnection);
mBound = false;
}
}
//start the service when clicked
public void onClick(View v) {
if (v == startButton)
{
//NEVER IN HERE
if (mBound) {
int num = mService.getRandomNumber();
Toast.makeText(this, "incoming number: " + num, Toast.LENGTH_LONG).show();
}
Toast.makeText(this, "the service should run now", Toast.LENGTH_LONG).show();
}
}
/** Defines callbacks for service binding, passed to bindService() */
private ServiceConnection mConnection = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName className,
IBinder service) {
// We've bound to LocalService, cast the IBinder and get LocalService instance
LocalBinder binder = (LocalBinder) service;
mService = binder.getService();
mBound = true;
if (mBound) {
// Call a method from the LocalService.
// However, if this call were something that might hang, then this request should
// occur in a separate thread to avoid slowing down the activity performance.
int num = mService.getRandomNumber();
String text = Integer.toString(num);
textBox.setText(text);
}
}
#Override
public void onServiceDisconnected(ComponentName arg0) {
mBound = false;
}
};
}
The Service I try to connect to:
package com.dieselboris.motioncapture;
import java.util.Random;
import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
public class LocalService extends Service {
// Binder given to clients
private final IBinder mBinder = new LocalBinder();
// Random number generator
private final Random mGenerator = new Random();
/**
* Class used for the client Binder. Because we know this service always
* runs in the same process as its clients, we don't need to deal with IPC.
*/
public class LocalBinder extends Binder {
LocalService getService() {
// Return this instance of LocalService so clients can call public methods
return LocalService.this;
}
}
#Override
public IBinder onBind(Intent intent) {
return mBinder;
}
/** method for clients */
public int getRandomNumber() {
return mGenerator.nextInt(100);
}
}
I get the following output from the emulator:
ERROR/AndroidRuntime(10878): FATAL EXCEPTION: main
ERROR/AndroidRuntime(10878): java.lang.NullPointerException
ERROR/AndroidRuntime(10878): at com.dieselboris.motioncapture.HelloMotionCaptureActivity.onClick(HelloMotionCaptureActivity.java:66)
ERROR/AndroidRuntime(10878): at android.view.View.performClick(View.java:2408)
ERROR/AndroidRuntime(10878): at android.view.View$PerformClick.run(View.java:8817)
ERROR/AndroidRuntime(10878): at android.os.Handler.handleCallback(Handler.java:587)
ERROR/AndroidRuntime(10878): at android.os.Handler.dispatchMessage(Handler.java:92)
ERROR/AndroidRuntime(10878): at android.os.Looper.loop(Looper.java:144)
ERROR/AndroidRuntime(10878): at android.app.ActivityThread.main(ActivityThread.java:4937)
ERROR/AndroidRuntime(10878): at java.lang.reflect.Method.invokeNative(Native Method)
ERROR/AndroidRuntime(10878): at java.lang.reflect.Method.invoke(Method.java:521)
ERROR/AndroidRuntime(10878): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
ERROR/AndroidRuntime(10878): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
ERROR/AndroidRuntime(10878): at dalvik.system.NativeStart.main(Native Method)
It seems that I call the public method from the service before it's initialized or the connection is not yet setup.
I followed the example on the developers site carefully and can't figure out what I am doing wrong.

My permissions weren't set correctly.
I had to insert a permission for the whole application and a "uses-permission" in application manifest.
Without permissions the intent is never delivered to the service.