Example: Communication between Activity and Service using Messaging
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I couldn't find any examples of how to send messages between an activity and a service, and I have spent far too many hours figuring this out. Here is an example project for others to reference.

This example allows you to start or stop a service directly, and separately bind/unbind from the service. When the service is running, it increments a number at 10 Hz. If the activity is bound to the Service, it will display the current value. Data is transferred as an Integer and as a String so you can see how to do that two different ways. There are also buttons in the activity to send messages to the service (changes the increment-by value).

Screenshot:

Screenshot of Android service messaging example

AndroidManifest.xml:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.exampleservice"
      android:versionCode="1"
      android:versionName="1.0">
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".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>
    <service android:name=".MyService"></service>
    </application>
    <uses-sdk android:minSdkVersion="8" />
</manifest>

res\values\strings.xml:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="app_name">ExampleService</string>
    <string name="service_started">Example Service started</string>
    <string name="service_label">Example Service Label</string>
</resources>

res\layout\main.xml:

<RelativeLayout
    android:id="@+id/RelativeLayout01"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" >

    <Button
        android:id="@+id/btnStart"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Start Service" >
    </Button>

    <Button
        android:id="@+id/btnStop"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:text="Stop Service" >
    </Button>
</RelativeLayout>

<RelativeLayout
    android:id="@+id/RelativeLayout02"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" >

    <Button
        android:id="@+id/btnBind"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Bind to Service" >
    </Button>

    <Button
        android:id="@+id/btnUnbind"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:text="Unbind from Service" >
    </Button>
</RelativeLayout>

<TextView
    android:id="@+id/textStatus"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="Status Goes Here"
    android:textSize="24sp" />

<TextView
    android:id="@+id/textIntValue"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="Integer Value Goes Here"
    android:textSize="24sp" />

<TextView
    android:id="@+id/textStrValue"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="String Value Goes Here"
    android:textSize="24sp" />

<RelativeLayout
    android:id="@+id/RelativeLayout03"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" >

    <Button
        android:id="@+id/btnUpby1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Increment by 1" >
    </Button>

    <Button
        android:id="@+id/btnUpby10"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:text="Increment by 10" >
    </Button>
</RelativeLayout>

src\com.exampleservice\MainActivity.java:

package com.exampleservice;

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.Handler;
import android.os.IBinder;
import android.os.Message;
import android.os.Messenger;
import android.os.RemoteException;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends Activity {
    Button btnStart, btnStop, btnBind, btnUnbind, btnUpby1, btnUpby10;
    TextView textStatus, textIntValue, textStrValue;
    Messenger mService = null;
    boolean mIsBound;
    final Messenger mMessenger = new Messenger(new IncomingHandler());

    class IncomingHandler extends Handler {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
            case MyService.MSG_SET_INT_VALUE:
                textIntValue.setText("Int Message: " + msg.arg1);
                break;
            case MyService.MSG_SET_STRING_VALUE:
                String str1 = msg.getData().getString("str1");
                textStrValue.setText("Str Message: " + str1);
                break;
            default:
                super.handleMessage(msg);
            }
        }
    }
    private ServiceConnection mConnection = new ServiceConnection() {
        public void onServiceConnected(ComponentName className, IBinder service) {
            mService = new Messenger(service);
            textStatus.setText("Attached.");
            try {
                Message msg = Message.obtain(null, MyService.MSG_REGISTER_CLIENT);
                msg.replyTo = mMessenger;
                mService.send(msg);
            }
            catch (RemoteException e) {
                // In this case the service has crashed before we could even do anything with it
            }
        }

        public void onServiceDisconnected(ComponentName className) {
            // This is called when the connection with the service has been unexpectedly disconnected - process crashed.
            mService = null;
            textStatus.setText("Disconnected.");
        }
    };

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        btnStart = (Button)findViewById(R.id.btnStart);
        btnStop = (Button)findViewById(R.id.btnStop);
        btnBind = (Button)findViewById(R.id.btnBind);
        btnUnbind = (Button)findViewById(R.id.btnUnbind);
        textStatus = (TextView)findViewById(R.id.textStatus);
        textIntValue = (TextView)findViewById(R.id.textIntValue);
        textStrValue = (TextView)findViewById(R.id.textStrValue);
        btnUpby1 = (Button)findViewById(R.id.btnUpby1);
        btnUpby10 = (Button)findViewById(R.id.btnUpby10);

        btnStart.setOnClickListener(btnStartListener);
        btnStop.setOnClickListener(btnStopListener);
        btnBind.setOnClickListener(btnBindListener);
        btnUnbind.setOnClickListener(btnUnbindListener);
        btnUpby1.setOnClickListener(btnUpby1Listener);
        btnUpby10.setOnClickListener(btnUpby10Listener);

        restoreMe(savedInstanceState);

        CheckIfServiceIsRunning();
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putString("textStatus", textStatus.getText().toString());
        outState.putString("textIntValue", textIntValue.getText().toString());
        outState.putString("textStrValue", textStrValue.getText().toString());
    }
    private void restoreMe(Bundle state) {
        if (state!=null) {
            textStatus.setText(state.getString("textStatus"));
            textIntValue.setText(state.getString("textIntValue"));
            textStrValue.setText(state.getString("textStrValue"));
        }
    }
    private void CheckIfServiceIsRunning() {
        //If the service is running when the activity starts, we want to automatically bind to it.
        if (MyService.isRunning()) {
            doBindService();
        }
    }

    private OnClickListener btnStartListener = new OnClickListener() {
        public void onClick(View v){
            startService(new Intent(MainActivity.this, MyService.class));
        }
    };
    private OnClickListener btnStopListener = new OnClickListener() {
        public void onClick(View v){
            doUnbindService();
            stopService(new Intent(MainActivity.this, MyService.class));
        }
    };
    private OnClickListener btnBindListener = new OnClickListener() {
        public void onClick(View v){
            doBindService();
        }
    };
    private OnClickListener btnUnbindListener = new OnClickListener() {
        public void onClick(View v){
            doUnbindService();
        }
    };
    private OnClickListener btnUpby1Listener = new OnClickListener() {
        public void onClick(View v){
            sendMessageToService(1);
        }
    };
    private OnClickListener btnUpby10Listener = new OnClickListener() {
        public void onClick(View v){
            sendMessageToService(10);
        }
    };
    private void sendMessageToService(int intvaluetosend) {
        if (mIsBound) {
            if (mService != null) {
                try {
                    Message msg = Message.obtain(null, MyService.MSG_SET_INT_VALUE, intvaluetosend, 0);
                    msg.replyTo = mMessenger;
                    mService.send(msg);
                }
                catch (RemoteException e) {
                }
            }
        }
    }


    void doBindService() {
        bindService(new Intent(this, MyService.class), mConnection, Context.BIND_AUTO_CREATE);
        mIsBound = true;
        textStatus.setText("Binding.");
    }
    void doUnbindService() {
        if (mIsBound) {
            // If we have received the service, and hence registered with it, then now is the time to unregister.
            if (mService != null) {
                try {
                    Message msg = Message.obtain(null, MyService.MSG_UNREGISTER_CLIENT);
                    msg.replyTo = mMessenger;
                    mService.send(msg);
                }
                catch (RemoteException e) {
                    // There is nothing special we need to do if the service has crashed.
                }
            }
            // Detach our existing connection.
            unbindService(mConnection);
            mIsBound = false;
            textStatus.setText("Unbinding.");
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        try {
            doUnbindService();
        }
        catch (Throwable t) {
            Log.e("MainActivity", "Failed to unbind from the service", t);
        }
    }
}

src\com.exampleservice\MyService.java:

package com.exampleservice;

import java.util.ArrayList;
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.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.os.Messenger;
import android.os.RemoteException;
import android.util.Log;

public class MyService extends Service {
    private NotificationManager nm;
    private Timer timer = new Timer();
    private int counter = 0, incrementby = 1;
    private static boolean isRunning = false;

    ArrayList<Messenger> mClients = new ArrayList<Messenger>(); // Keeps track of all current registered clients.
    int mValue = 0; // Holds last value set by a client.
    static final int MSG_REGISTER_CLIENT = 1;
    static final int MSG_UNREGISTER_CLIENT = 2;
    static final int MSG_SET_INT_VALUE = 3;
    static final int MSG_SET_STRING_VALUE = 4;
    final Messenger mMessenger = new Messenger(new IncomingHandler()); // Target we publish for clients to send messages to IncomingHandler.


    @Override
    public IBinder onBind(Intent intent) {
        return mMessenger.getBinder();
    }
    class IncomingHandler extends Handler { // Handler of incoming messages from clients.
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
            case MSG_REGISTER_CLIENT:
                mClients.add(msg.replyTo);
                break;
            case MSG_UNREGISTER_CLIENT:
                mClients.remove(msg.replyTo);
                break;
            case MSG_SET_INT_VALUE:
                incrementby = msg.arg1;
                break;
            default:
                super.handleMessage(msg);
            }
        }
    }
    private void sendMessageToUI(int intvaluetosend) {
        for (int i=mClients.size()-1; i>=0; i--) {
            try {
                // Send data as an Integer
                mClients.get(i).send(Message.obtain(null, MSG_SET_INT_VALUE, intvaluetosend, 0));

                //Send data as a String
                Bundle b = new Bundle();
                b.putString("str1", "ab" + intvaluetosend + "cd");
                Message msg = Message.obtain(null, MSG_SET_STRING_VALUE);
                msg.setData(b);
                mClients.get(i).send(msg);

            }
            catch (RemoteException e) {
                // The client is dead. Remove it from the list; we are going through the list from back to front so this is safe to do inside the loop.
                mClients.remove(i);
            }
        }
    }

    @Override
    public void onCreate() {
        super.onCreate();
        Log.i("MyService", "Service Started.");
        showNotification();
        timer.scheduleAtFixedRate(new TimerTask(){ public void run() {onTimerTick();}}, 0, 100L);
        isRunning = true;
    }
    private void showNotification() {
        nm = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
        // In this sample, we'll use the same text for the ticker and the expanded notification
        CharSequence text = getText(R.string.service_started);
        // Set the icon, scrolling text and timestamp
        Notification notification = new Notification(R.drawable.icon, text, System.currentTimeMillis());
        // The PendingIntent to launch our activity if the user selects this notification
        PendingIntent contentIntent = PendingIntent.getActivity(this, 0, new Intent(this, MainActivity.class), 0);
        // Set the info for the views that show in the notification panel.
        notification.setLatestEventInfo(this, getText(R.string.service_label), text, contentIntent);
        // Send the notification.
        // We use a layout id because it is a unique number.  We use it later to cancel.
        nm.notify(R.string.service_started, notification);
    }
    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.i("MyService", "Received start id " + startId + ": " + intent);
        return START_STICKY; // run until explicitly stopped.
    }

    public static boolean isRunning()
    {
        return isRunning;
    }


    private void onTimerTick() {
        Log.i("TimerTick", "Timer doing work." + counter);
        try {
            counter += incrementby;
            sendMessageToUI(counter);

        }
        catch (Throwable t) { //you should always ultimately catch all exceptions in timer tasks.
            Log.e("TimerTick", "Timer Tick Failed.", t);
        }
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (timer != null) {timer.cancel();}
        counter=0;
        nm.cancel(R.string.service_started); // Cancel the persistent notification.
        Log.i("MyService", "Service Stopped.");
        isRunning = false;
    }
}
Hairworm answered 29/11, 2010 at 1:50 Comment(15)
i think it will help you ---------- #1465353Fadden
If you don't need ot send a lot of data, you can use Intents.Loeffler
Or Broadcasts in general!Szymanowski
Using broadcast receivers is exactly what I neededHutner
Great example! Another nice feature: If you put android:process=:myservicename attribute to the service tag of your service in your manifest.xml, like: <service android:name="sname" android:process=":myservicename" />, then it will run your service as a different process - thus in a different thread. This means, that any heavy calculation done/long request by the service wont hang your UI thread.Galliett
can you post the link from where you got this example code..?Neville
I know you took the effort to do this, but it would make more sense to put it up on github or a similar source-code sharing site and posting the link here. It's easier for people to get it up and running this way.Rillet
I used your code to create a very generic way to communicate between a custom Service and an Activity. If anyone is interested, checkout the blog post or the full code on Launchpad.Biotope
Great example maybe someone at developer.android.com should link their Service tutorial to this!Neutral
I don't think your assumption about concurrent modification is accurate.Ancheta
Messaging is really necessary only if your service can be called by other applications. Otherwise you may stick with a Binder that returns you a reference to the Service and just call public methods of it.Disforest
You should have made the question and then create an answer yourself, not answer the problem on the question. Great example though ;)Siffre
You can use SharedPreferences as a trick , to get result from and Activity back to a service SOStovall
I really liked your example, the one thing I didn't liked is the "sendMessageToUI" method. it's not very smart to use backwards for loops just to avoid concurrency errors while removing members of the list. that's why iterators exist. I have written an example here : gist.github.com/JozeRi/73bd3e4191a4c70ca164Argumentation
If you wish, here's a nice example of how to use Messenger class on Android: https://mcmap.net/q/65622/-toast-not-displayed-in-bound-service-example-using-messenger/878126Zindman
P
48

Look at the LocalService example.

Your Service returns an instance of itself to consumers who call onBind. Then you can directly interact with the service, e.g. registering your own listener interface with the service, so that you can get callbacks.

Prat answered 22/1, 2011 at 11:10 Comment(4)
The only problem with that is that it wouldn't be using a Messenger, so it wouldn't answer this pseudo-question. I've used a LocalService, but I was glad to find an example of a Messenger/Handler. I don't believe a LocalService can be put in another process.Blasphemy
@Christoper-Orr: I'm very thankful you've posted that link of the Android BroadcastReceiver tutorial. I've used a LocalBroadcastManager to continuously exchange data between two Activity instances.Landrum
The problem with LocalBroadcastManager is that it's non-blocking and you have to wait for results. Sometimes you want immediate results.Fustian
Can you please help me with this question #51508546Lasalle
P
21

For sending data to a service you can use:

Intent intent = new Intent(getApplicationContext(), YourService.class);
intent.putExtra("SomeData","ItValue");
startService(intent);

And after in service in onStartCommand() get data from intent.

For sending data or event from a service to an application (for one or more activities):

private void sendBroadcastMessage(String intentFilterName, int arg1, String extraKey) {
    Intent intent = new Intent(intentFilterName);
    if (arg1 != -1 && extraKey != null) {
        intent.putExtra(extraKey, arg1);
    }
    sendBroadcast(intent);
}

This method is calling from your service. You can simply send data for your Activity.

private void someTaskInYourService(){

    //For example you downloading from server 1000 files
    for(int i = 0; i < 1000; i++) {
        Thread.sleep(5000) // 5 seconds. Catch in try-catch block
        sendBroadCastMessage(Events.UPDATE_DOWNLOADING_PROGRESSBAR, i,0,"up_download_progress");
    }

For receiving an event with data, create and register method registerBroadcastReceivers() in your activity:

private void registerBroadcastReceivers(){
    broadcastReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            int arg1 = intent.getIntExtra("up_download_progress",0);
            progressBar.setProgress(arg1);
        }
    };
    IntentFilter progressfilter = new IntentFilter(Events.UPDATE_DOWNLOADING_PROGRESS);
    registerReceiver(broadcastReceiver,progressfilter);

For sending more data, you can modify method sendBroadcastMessage();. Remember: you must register broadcasts in onResume() & unregister in onStop() methods!

UPDATE

Please don't use my type of communication between Activity & Service. This is the wrong way. For a better experience please use special libs, such us:

1) EventBus from greenrobot

2) Otto from Square Inc

P.S. I'm only using EventBus from greenrobot in my projects,

Panto answered 4/2, 2014 at 23:38 Comment(5)
where should i need to register reciever in onResume and in onStop may i need to do in activity ?Throwaway
Yes. For receive event from service you must register broadcast in onResume. Remember that you must unregister broadcast in onStop. Now, i'm don't recommend use my method. Please use special libs for communicate with other views/activities/services such as EventBus github.com/greenrobot/EventBus or Otto github.com/square/ottoPanto
can u pls help me how can i use this i stuck in my project in service communicationThrowaway
Has Google recommended against this, or are you just saying it's "wrong" because you think the other solutions are better?Kermes
plus one for providing links to EventBus and Otto.Etymon
C
14

Note: You don't need to check if your service is running, CheckIfServiceIsRunning(), because bindService() will start it if it isn't running.

Also: if you rotate the phone you don't want it to bindService() again, because onCreate() will be called again. Be sure to define onConfigurationChanged() to prevent this.

Compton answered 24/1, 2011 at 6:46 Comment(3)
In my case, I don't need the service running all the time. If the service is already running when the activity starts, then I want to bind to it. If the service isn't running when the activity starts, I want to leave the service stopped.Hairworm
I am not sure this is true, bindService does not start the service, can you please point to the documentation?Prostration
developer.android.com/reference/android/app/Service.html The first paragraph states Services can be started with Context.startService() and Context.bindService()Compton
C
8

Everything is fine.Good example of activity/service communication using Messenger.

One comment : the method MyService.isRunning() is not required.. bindService() can be done any number of times. no harm in that.

If MyService is running in a different process then the static function MyService.isRunning() will always return false. So there is no need of this function.

Counterforce answered 5/11, 2012 at 10:58 Comment(0)
T
8
Message msg = Message.obtain(null, 2, 0, 0);
                    Bundle bundle = new Bundle();
                    bundle.putString("url", url);
                    bundle.putString("names", names);
                    bundle.putString("captions",captions); 
                    msg.setData(bundle);

So you send it to the service. Afterward receive.

Topcoat answered 16/1, 2013 at 17:30 Comment(0)
W
2

This is how I implemeted Activity->Service Communication: on my Activity i had

private static class MyResultReciever extends ResultReceiver {
     /**
     * Create a new ResultReceive to receive results.  Your
     * {@link #onReceiveResult} method will be called from the thread running
     * <var>handler</var> if given, or from an arbitrary thread if null.
     *
     * @param handler
     */
     public MyResultReciever(Handler handler) {
         super(handler);
     }

     @Override
     protected void onReceiveResult(int resultCode, Bundle resultData) {
         if (resultCode == 100) {
             //dostuff
         }
     }

And then I used this to start my Service

protected void onCreate(Bundle savedInstanceState) {
MyResultReciever resultReciever = new MyResultReciever(handler);
        service = new Intent(this, MyService.class);
        service.putExtra("receiver", resultReciever);
        startService(service);
}

In my Service i had

public int onStartCommand(Intent intent, int flags, int startId) {
    if (intent != null)
        resultReceiver = intent.getParcelableExtra("receiver");
    return Service.START_STICKY;
}

Hope this Helps

Wariness answered 26/6, 2016 at 16:53 Comment(0)
W
0

Seems to me you could've saved some memory by declaring your activity with "implements Handler.Callback"

Wifehood answered 7/1, 2013 at 21:29 Comment(0)
B
0

Great tutorial, fantastic presentation. Neat, simple, short and very explanatory. Although, notification.setLatestEventInfo(this, getText(R.string.service_label), text, contentIntent); method is no more. As trante stated here, good approach would be:

private static final int NOTIFICATION_ID = 45349;

private void showNotification() {
    NotificationCompat.Builder builder =
            new NotificationCompat.Builder(this)
                    .setSmallIcon(R.mipmap.ic_launcher)
                    .setContentTitle("My Notification Title")
                    .setContentText("Something interesting happened");

    Intent targetIntent = new Intent(this, MainActivity.class);
    PendingIntent contentIntent = PendingIntent.getActivity(this, 0, targetIntent, PendingIntent.FLAG_UPDATE_CURRENT);
    builder.setContentIntent(contentIntent);
    _nManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
    _nManager.notify(NOTIFICATION_ID, builder.build());
}

@Override
public void onDestroy() {
    super.onDestroy();
    if (_timer != null) {_timer.cancel();}
    _counter=0;
    _nManager.cancel(NOTIFICATION_ID); // Cancel the persistent notification.
    Log.i("PlaybackService", "Service Stopped.");
    _isRunning = false;
}

Checked myself, everything works like a charm (activity and service names may differ from original).

Birchard answered 9/1, 2017 at 22:8 Comment(0)
N
0

I have seen all answers. I want tell most robust way now a day. That will make you communicate between Activity - Service - Dialog - Fragments (Everything).

EventBus

This lib which i am using in my projects has great features related to messaging.

EventBus in 3 steps

  1. Define events:

    public static class MessageEvent { /* Additional fields if needed */ }

  2. Prepare subscribers:

Declare and annotate your subscribing method, optionally specify a thread mode:

@Subscribe(threadMode = ThreadMode.MAIN) 
public void onMessageEvent(MessageEvent event) {/* Do something */};

Register and unregister your subscriber. For example on Android, activities and fragments should usually register according to their life cycle:

@Override
public void onStart() {
    super.onStart();
    EventBus.getDefault().register(this);
}

@Override
public void onStop() {
    super.onStop();
    EventBus.getDefault().unregister(this);
}
  1. Post events:

    EventBus.getDefault().post(new MessageEvent());

Just add this dependency in your app level gradle

compile 'org.greenrobot:eventbus:3.1.1'
Neume answered 5/7, 2018 at 9:25 Comment(1)
It does not have IPC, so we need messengers in both ways. AIDL is deprecatedSturges
S
0

1- In the Service class:

class MyService : Service() {

private lateinit var messenger: Messenger

private val handler = object : Handler() {
    override fun handleMessage(msg: Message) {
        when (msg.what) {
            // Handle message from the Activity
            // Perform any action based on the message
        }
    }
}

private val messengerCallback = Messenger(handler)

override fun onBind(intent: Intent): IBinder {
    messenger = Messenger(messengerCallback)
    return messenger.binder
}

}

2- In the Activity class:

class MyActivity : AppCompatActivity() {

private lateinit var messenger: Messenger

private val serviceConnection = object : ServiceConnection {
    override fun onServiceConnected(className: ComponentName, service: IBinder) {
        messenger = Messenger(service)
        sendMessageToService("Hello from Activity")
    }

    override fun onServiceDisconnected(arg0: ComponentName) {}
}

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    bindService(Intent(this, MyService::class.java), serviceConnection, Context.BIND_AUTO_CREATE)
}

private fun sendMessageToService(message: String) {
    val msg = Message.obtain(null, 0, 0, 0)
    val bundle = Bundle()
    bundle.putString("message", message)
    msg.data = bundle
    try {
        messenger.send(msg)
    } catch (e: RemoteException) {
        e.printStackTrace()
    }
}

}

Siddons answered 11/2, 2023 at 14:15 Comment(0)

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